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<li class="toctree-l2"><a class="reference internal" href="get-started/espressif.html">Espressif (ESP32)</a><ul>
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<li class="toctree-l3"><a class="reference internal" href="get-started/espressif.html#use-lvgl-esp32-drivers-in-your-project">Use lvgl_esp32_drivers in your project</a><ul>
<li class="toctree-l4"><a class="reference internal" href="get-started/espressif.html#support-for-esp32-s2">Support for ESP32-S2</a></li>
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<li class="toctree-l2"><a class="reference internal" href="get-started/arduino.html">Arduino</a><ul>
<li class="toctree-l3"><a class="reference internal" href="get-started/arduino.html#get-the-lvgl-ardunio-library">Get the LVGL Ardunio library</a></li>
<li class="toctree-l3"><a class="reference internal" href="get-started/arduino.html#set-up-drivers">Set up drivers</a></li>
<li class="toctree-l3"><a class="reference internal" href="get-started/arduino.html#configure-lvgl">Configure LVGL</a></li>
<li class="toctree-l3"><a class="reference internal" href="get-started/arduino.html#configure-the-examples">Configure the examples</a></li>
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<li class="toctree-l2"><a class="reference internal" href="get-started/micropython.html">Micropython</a><ul>
<li class="toctree-l3"><a class="reference internal" href="get-started/micropython.html#what-is-micropython">What is Micropython?</a><ul>
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<li class="toctree-l3"><a class="reference internal" href="get-started/micropython.html#why-micropython-lvgl">Why Micropython + LVGL?</a><ul>
<li class="toctree-l4"><a class="reference internal" href="get-started/micropython.html#here-are-some-advantages-of-using-lvgl-in-micropython">Here are some advantages of using LVGL in Micropython:</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/micropython.html#micropython-lvgl-could-be-used-for">Micropython + LVGL could be used for:</a></li>
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<li class="toctree-l3"><a class="reference internal" href="get-started/micropython.html#so-what-does-it-look-like">So what does it look like?</a><ul>
<li class="toctree-l4"><a class="reference internal" href="get-started/micropython.html#a-simple-example">A simple example</a></li>
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<li class="toctree-l3"><a class="reference internal" href="get-started/micropython.html#how-can-i-use-it">How can I use it?</a><ul>
<li class="toctree-l4"><a class="reference internal" href="get-started/micropython.html#online-simulator">Online Simulator</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/micropython.html#pc-simulator">PC Simulator</a></li>
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<li class="toctree-l2"><a class="reference internal" href="get-started/nuttx.html">NuttX RTOS</a><ul>
<li class="toctree-l3"><a class="reference internal" href="get-started/nuttx.html#what-is-nuttx">What is NuttX?</a><ul>
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<li class="toctree-l3"><a class="reference internal" href="get-started/nuttx.html#why-nuttx-lvgl">Why NuttX + LVGL?</a><ul>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#here-are-some-advantages-of-using-lvgl-in-nuttx">Here are some advantages of using LVGL in NuttX</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#nuttx-lvgl-could-be-used-for">NuttX + LVGL could be used for</a></li>
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<li class="toctree-l3"><a class="reference internal" href="get-started/nuttx.html#how-to-get-started-with-nuttx-and-lvgl">How to get started with NuttX and LVGL?</a><ul>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#first-you-need-to-install-the-pre-requisite-on-your-system">First you need to install the pre-requisite on your system</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#now-let-s-to-create-a-workspace-to-save-our-files">Now let's to create a workspace to save our files</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#clone-the-nuttx-and-apps-repositories">Clone the NuttX and Apps repositories:</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#configure-nuttx-to-use-the-stm32f429i-disco-board-and-the-lvgl-demo">Configure NuttX to use the stm32f429i-disco board and the LVGL Demo</a></li>
<li class="toctree-l4"><a class="reference internal" href="get-started/nuttx.html#flashing-the-firmware-in-the-board-using-openocd">Flashing the firmware in the board using OpenOCD:</a></li>
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<li class="toctree-l3"><a class="reference internal" href="get-started/nuttx.html#where-can-i-find-more-information">Where can I find more information?</a></li>
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<li class="toctree-l1"><a class="reference internal" href="porting/index.html">Porting</a><ul>
<li class="toctree-l2"><a class="reference internal" href="porting/project.html">Set-up a project</a><ul>
<li class="toctree-l3"><a class="reference internal" href="porting/project.html#get-the-library">Get the library</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/project.html#configuration-file">Configuration file</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/project.html#initialization">Initialization</a></li>
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<li class="toctree-l2"><a class="reference internal" href="porting/display.html">Display interface</a><ul>
<li class="toctree-l3"><a class="reference internal" href="porting/display.html#draw-buffer">Draw buffer</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/display.html#display-driver">Display driver</a><ul>
<li class="toctree-l4"><a class="reference internal" href="porting/display.html#mandatory-fields">Mandatory fields</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/display.html#optional-fields">Optional fields</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/display.html#examples">Examples</a></li>
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<li class="toctree-l3"><a class="reference internal" href="porting/display.html#rotation">Rotation</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/display.html#further-reading">Further reading</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/display.html#api">API</a></li>
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<li class="toctree-l2"><a class="reference internal" href="porting/indev.html">Input device interface</a><ul>
<li class="toctree-l3"><a class="reference internal" href="porting/indev.html#types-of-input-devices">Types of input devices</a><ul>
<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#touchpad-mouse-or-any-pointer">Touchpad, mouse or any pointer</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#keypad-or-keyboard">Keypad or keyboard</a></li>
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<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#button">Button</a></li>
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<li class="toctree-l3"><a class="reference internal" href="porting/indev.html#other-features">Other features</a><ul>
<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#parameters">Parameters</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#feedback">Feedback</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#associating-with-a-display">Associating with a display</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/indev.html#buffered-reading">Buffered reading</a></li>
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<li class="toctree-l3"><a class="reference internal" href="porting/indev.html#further-reading">Further reading</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/indev.html#api">API</a></li>
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<li class="toctree-l2"><a class="reference internal" href="porting/tick.html">Tick interface</a><ul>
<li class="toctree-l3"><a class="reference internal" href="porting/tick.html#api">API</a></li>
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<li class="toctree-l2"><a class="reference internal" href="porting/task-handler.html">Task Handler</a></li>
<li class="toctree-l2"><a class="reference internal" href="porting/sleep.html">Sleep management</a></li>
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<li class="toctree-l3"><a class="reference internal" href="porting/os.html#tasks-and-threads">Tasks and threads</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/os.html#interrupts">Interrupts</a></li>
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<li class="toctree-l2"><a class="reference internal" href="porting/log.html">Logging</a><ul>
<li class="toctree-l3"><a class="reference internal" href="porting/log.html#log-level">Log level</a></li>
<li class="toctree-l3"><a class="reference internal" href="porting/log.html#printing-logs">Printing logs</a><ul>
<li class="toctree-l4"><a class="reference internal" href="porting/log.html#logging-with-printf">Logging with printf</a></li>
<li class="toctree-l4"><a class="reference internal" href="porting/log.html#custom-log-function">Custom log function</a></li>
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<li class="toctree-l3"><a class="reference internal" href="porting/log.html#add-logs">Add logs</a></li>
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<li class="toctree-l1"><a class="reference internal" href="overview/index.html">Overview</a><ul>
<li class="toctree-l2"><a class="reference internal" href="overview/object.html">Objects</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/object.html#attributes">Attributes</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#basic-attributes">Basic attributes</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#specific-attributes">Specific attributes</a></li>
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<li class="toctree-l3"><a class="reference internal" href="overview/object.html#working-mechanisms">Working mechanisms</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#parent-child-structure">Parent-child structure</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#moving-together">Moving together</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#visibility-only-on-the-parent">Visibility only on the parent</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#create-and-delete-objects">Create and delete objects</a></li>
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<li class="toctree-l3"><a class="reference internal" href="overview/object.html#screens">Screens</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#create-screens">Create screens</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#get-the-active-screen">Get the active screen</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#load-screens">Load screens</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#layers">Layers</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/object.html#handling-multiple-displays">Handling multiple displays</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/object.html#parts">Parts</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/object.html#states">States</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/coords.html">Positions, sizes, and layouts</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#overview">Overview</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#units">Units</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#boxing-model">Boxing model</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#important-notes">Important notes</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#position">Position</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#simple-way">Simple way</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#align">Align</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#size">Size</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#id1">Simple way</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#using-styles">Using styles</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#translation">Translation</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#transformation">Transformation</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#min-and-max-size">Min and Max size</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#layout">Layout</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#id2">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#built-in-layout">Built-in layout</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#flags">Flags</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/coords.html#adding-new-layouts">Adding new layouts</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/coords.html#examples">Examples</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/style.html">Styles</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#states">States</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#cascading-styles">Cascading styles</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#inheritance">Inheritance</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#parts">Parts</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#initialize-styles-and-set-get-properties">Initialize styles and set/get properties</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#add-and-remove-styles-to-a-widget">Add and remove styles to a widget</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#add-styles">Add styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#remove-styles">Remove styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#report-style-changes">Report style changes</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#get-a-property-s-value-on-an-object">Get a property's value on an object</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#local-styles">Local styles</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#properties">Properties</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#typical-background-properties">Typical background properties</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#transitions">Transitions</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#color-filter">Color filter</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#themes">Themes</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#extending-themes">Extending themes</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#examples">Examples</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style.html#micropython">MicroPython</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/style-props.html">Style properties</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#size-and-position">Size and position</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#width">width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#min-width">min_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#max-width">max_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#height">height</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#min-height">min_height</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#max-height">max_height</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#x">x</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#y">y</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#align">align</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#transform-width">transform_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#transform-height">transform_height</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#translate-x">translate_x</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#translate-y">translate_y</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#transform-zoom">transform_zoom</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#transform-angle">transform_angle</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#padding">Padding</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#pad-top">pad_top</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#pad-bottom">pad_bottom</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#pad-left">pad_left</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#pad-right">pad_right</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#pad-row">pad_row</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#pad-column">pad_column</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#miscellaneous">Miscellaneous</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#radius">radius</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#clip-corner">clip_corner</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#opa">opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#color-filter-dsc">color_filter_dsc</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#color-filter-opa">color_filter_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#anim-time">anim_time</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#anim-speed">anim_speed</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#transition">transition</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#blend-mode">blend_mode</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#layout">layout</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#base-dir">base_dir</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#background">Background</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-color">bg_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-opa">bg_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-grad-color">bg_grad_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-grad-dir">bg_grad_dir</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-main-stop">bg_main_stop</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-grad-stop">bg_grad_stop</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-img-src">bg_img_src</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-img-opa">bg_img_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-img-recolor">bg_img_recolor</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-img-recolor-opa">bg_img_recolor_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#bg-img-tiled">bg_img_tiled</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#border">Border</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#border-color">border_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#border-opa">border_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#border-width">border_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#border-side">border_side</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#border-post">border_post</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#text">Text</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-color">text_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-opa">text_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-font">text_font</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-letter-space">text_letter_space</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-line-space">text_line_space</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-decor">text_decor</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#text-align">text_align</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#image">Image</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#img-opa">img_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#img-recolor">img_recolor</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#img-recolor-opa">img_recolor_opa</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#outline">Outline</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#outline-width">outline_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#outline-color">outline_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#outline-opa">outline_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#outline-pad">outline_pad</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#shadow">Shadow</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#shadow-width">shadow_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#shadow-ofs-x">shadow_ofs_x</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#shadow-ofs-y">shadow_ofs_y</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#shadow-spread">shadow_spread</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#shadow-color">shadow_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#shadow-opa">shadow_opa</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#line">Line</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#line-width">line_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#line-dash-width">line_dash_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#line-dash-gap">line_dash_gap</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#line-rounded">line_rounded</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#line-color">line_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#line-opa">line_opa</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/style-props.html#arc">Arc</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#arc-width">arc_width</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#arc-rounded">arc_rounded</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#arc-color">arc_color</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#arc-opa">arc_opa</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/style-props.html#arc-img-src">arc_img_src</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/scroll.html">Scroll</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/scroll.html#overview">Overview</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#scrollbar">Scrollbar</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#events">Events</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/scroll.html#basic-example">Basic example</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/scroll.html#features-of-scrolling">Features of scrolling</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#scrollable">Scrollable</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#scroll-chain">Scroll chain</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#scroll-momentum">Scroll momentum</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#elastic-scroll">Elastic scroll</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#snapping">Snapping</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#scroll-one">Scroll one</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#scroll-on-focus">Scroll on focus</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/scroll.html#scroll-manually">Scroll manually</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/scroll.html#self-size">Self size</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/scroll.html#examples">Examples</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/scroll.html#micropython">MicroPython</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/layer.html">Layers</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/layer.html#order-of-creation">Order of creation</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/layer.html#bring-to-the-foreground">Bring to the foreground</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/layer.html#top-and-sys-layers">Top and sys layers</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/event.html">Events</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#add-events-to-the-object">Add events to the object</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#remove-event-s-from-an-object">Remove event(s) from an object</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#event-codes">Event codes</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#input-device-events">Input device events</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#drawing-events">Drawing events</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#other-events">Other events</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#special-events">Special events</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#custom-events">Custom events</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#sending-events">Sending events</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#refresh-event">Refresh event</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#fields-of-lv-event-t">Fields of lv_event_t</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#event-bubbling">Event bubbling</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/event.html#examples">Examples</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/event.html#micropython">MicroPython</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/indev.html">Input devices</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/indev.html#pointers">Pointers</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/indev.html#keypad-and-encoder">Keypad and encoder</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/indev.html#groups">Groups</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/indev.html#styling">Styling</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/indev.html#api">API</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/indev.html#input-device">Input device</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/indev.html#id1">Groups</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/display.html">Displays</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/display.html#multiple-display-support">Multiple display support</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/display.html#using-only-one-display">Using only one display</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/display.html#mirror-display">Mirror display</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/display.html#split-image">Split image</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/display.html#screens">Screens</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/display.html#transparent-screens">Transparent screens</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/display.html#features-of-displays">Features of displays</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/display.html#inactivity">Inactivity</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/display.html#background">Background</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/display.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/color.html">Colors</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/color.html#creating-colors">Creating colors</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/color.html#rgb">RGB</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/color.html#hsv">HSV</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/color.html#palette">Palette</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/color.html#modify-and-mix-colors">Modify and mix colors</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/color.html#built-in-colors">Built-in colors</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/color.html#opacity">Opacity</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/color.html#color-types">Color types</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/color.html#convert-color">Convert color</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/color.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/font.html">Fonts</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#unicode-support">Unicode support</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#built-in-fonts">Built-in fonts</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/font.html#normal-fonts">Normal fonts</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/font.html#special-fonts">Special fonts</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#special-features">Special features</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/font.html#bidirectional-support">Bidirectional support</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/font.html#arabic-and-persian-support">Arabic and Persian support</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/font.html#subpixel-rendering">Subpixel rendering</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/font.html#compress-fonts">Compress fonts</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#add-new-font">Add new font</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#add-new-symbols">Add new symbols</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#load-font-at-run-time">Load font at run-time</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/font.html#add-a-new-font-engine">Add a new font engine</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/image.html">Images</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/image.html#store-images">Store images</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#variables">Variables</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#files">Files</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/image.html#color-formats">Color formats</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/image.html#add-and-use-images">Add and use images</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#online-converter">Online converter</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#manually-create-an-image">Manually create an image</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#use-images">Use images</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/image.html#image-decoder">Image decoder</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#custom-image-formats">Custom image formats</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#register-an-image-decoder">Register an image decoder</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#manually-use-an-image-decoder">Manually use an image decoder</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/image.html#image-caching">Image caching</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#cache-size">Cache size</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#value-of-images">Value of images</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#memory-usage">Memory usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#clean-the-cache">Clean the cache</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/image.html#api">API</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/image.html#image-buffer">Image buffer</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/file-system.html">File system</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/file-system.html#ready-to-use-drivers">Ready to use drivers</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/file-system.html#add-a-driver">Add a driver</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/file-system.html#registering-a-driver">Registering a driver</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/file-system.html#implementing-the-callbacks">Implementing the callbacks</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/file-system.html#other-callbacks">Other callbacks</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/file-system.html#usage-example">Usage example</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/file-system.html#use-drivers-for-images">Use drivers for images</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/file-system.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/animation.html">Animations</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/animation.html#create-an-animation">Create an animation</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/animation.html#animation-path">Animation path</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/animation.html#speed-vs-time">Speed vs time</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/animation.html#delete-animations">Delete animations</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/animation.html#examples">Examples</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/animation.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/animation.html#micropython">MicroPython</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="overview/animation.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/timer.html">Timers</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#create-a-timer">Create a timer</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#ready-and-reset">Ready and Reset</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#set-parameters">Set parameters</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#repeat-count">Repeat count</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#measure-idle-time">Measure idle time</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#asynchronous-calls">Asynchronous calls</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/timer.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/drawing.html">Drawing</a><ul>
<li class="toctree-l3"><a class="reference internal" href="overview/drawing.html#mechanism-of-screen-refreshing">Mechanism of screen refreshing</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/drawing.html#masking">Masking</a></li>
<li class="toctree-l3"><a class="reference internal" href="overview/drawing.html#hook-drawing">Hook drawing</a><ul>
<li class="toctree-l4"><a class="reference internal" href="overview/drawing.html#main-drawing">Main drawing</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/drawing.html#post-drawing">Post drawing</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/drawing.html#part-drawing">Part drawing</a></li>
<li class="toctree-l4"><a class="reference internal" href="overview/drawing.html#others">Others</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="overview/new_widget.html">New widget</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="widgets/index.html">Widgets</a><ul>
<li class="toctree-l2"><a class="reference internal" href="widgets/obj.html">Base object (lv_obj)</a><ul>
<li class="toctree-l3"><a class="reference internal" href="widgets/obj.html#overview">Overview</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#coordinates">Coordinates</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#parents-and-children">Parents and children</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#screens">Screens</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#styles">Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#flags">Flags</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#groups">Groups</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#extended-click-area">Extended click area</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/obj.html#id1">Events</a></li>
<li class="toctree-l3"><a class="reference internal" href="widgets/obj.html#keys">Keys</a></li>
<li class="toctree-l3"><a class="reference internal" href="widgets/obj.html#example">Example</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/obj.html#micropython">MicroPython</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/obj.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="widgets/core/index.html">Core widgets</a><ul>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/arc.html">Arc (lv_arc)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/arc.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/bar.html">Bar (lv_bar)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/bar.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/btn.html">Button (lv_btn)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btn.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/btnmatrix.html">Button matrix (lv_btnmatrix)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/btnmatrix.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/canvas.html">Canvas (lv_canvas)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/canvas.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/checkbox.html">Checkbox (lv_checkbox)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/checkbox.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/dropdown.html">Drop-down list (lv_dropdown)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#id1">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/dropdown.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/img.html">Image (lv_img)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#transformations">Transformations</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/img.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/label.html">Label (lv_label)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/label.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/line.html">Line (lv_line)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/line.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/roller.html">Roller (lv_roller)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/roller.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/slider.html">Slider (lv_slider)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/slider.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/switch.html">Switch (lv_switch)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/switch.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/table.html">Table (lv_table)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/table.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/core/textarea.html">Text area (lv_textarea)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/core/textarea.html#api">API</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="widgets/extra/index.html">Extra widgets</a><ul>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/calendar.html">Calendar (lv_calendar)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#headers">Headers</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/calendar.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/chart.html">Chart (lv_chart)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/chart.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/colorwheel.html">Color wheel (lv_colorwheel)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/colorwheel.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/imgbtn.html">Image button (lv_imgbtn)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/imgbtn.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/keyboard.html">Keyboard (lv_keyboard)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#examples">Examples</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/keyboard.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/led.html">LED (lv_led)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/led.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/list.html">List (lv_list)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/list.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/meter.html">Meter (lv_meter)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/meter.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/msgbox.html">Message box (lv_msgbox)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/msgbox.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/span.html">Span (lv_span)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/span.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/spinbox.html">Spinbox (lv_spinbox)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#api">API</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinbox.html#id1">Example</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/spinner.html">Spinner (lv_spinner)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/spinner.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/tabview.html">Tabview (lv_tabview)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tabview.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/tileview.html">Tile view (lv_tileview)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/tileview.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="widgets/extra/win.html">Window (lv_win)</a><ul>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#overview">Overview</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#parts-and-styles">Parts and Styles</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#usage">Usage</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#get-the-parts">Get the parts</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#events">Events</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#keys">Keys</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#example">Example</a></li>
<li class="toctree-l4"><a class="reference internal" href="widgets/extra/win.html#api">API</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="layouts/index.html">Layouts</a><ul>
<li class="toctree-l2"><a class="reference internal" href="layouts/flex.html">Flex</a><ul>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#overview">Overview</a></li>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#terms">Terms</a></li>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#simple-interface">Simple interface</a><ul>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#flex-flow">Flex flow</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#flex-align">Flex align</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#flex-grow">Flex grow</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#style-interface">Style interface</a></li>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#other-features">Other features</a><ul>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#rtl">RTL</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#new-track">New track</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#example">Example</a><ul>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/flex.html#micropython">MicroPython</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="layouts/flex.html#api">API</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="layouts/grid.html">Grid</a><ul>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#overview">Overview</a></li>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#terms">Terms</a></li>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#simple-interface">Simple interface</a><ul>
<li class="toctree-l4"><a class="reference internal" href="layouts/grid.html#grid-descriptors">Grid descriptors</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/grid.html#grid-items">Grid items</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/grid.html#grid-align">Grid align</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#style-interface">Style interface</a></li>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#other-features">Other features</a><ul>
<li class="toctree-l4"><a class="reference internal" href="layouts/grid.html#rtl">RTL</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#example">Example</a><ul>
<li class="toctree-l4"><a class="reference internal" href="layouts/grid.html#c">C</a></li>
<li class="toctree-l4"><a class="reference internal" href="layouts/grid.html#micropython">MicroPython</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="layouts/grid.html#api">API</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="CONTRIBUTING.html">Contributing</a><ul>
<li class="toctree-l2"><a class="reference internal" href="CONTRIBUTING.html#introduction">Introduction</a></li>
<li class="toctree-l2"><a class="reference internal" href="CONTRIBUTING.html#pull-request">Pull request</a><ul>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#from-github">From GitHub</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#from-command-line">From command line</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="CONTRIBUTING.html#developer-certification-of-origin-dco">Developer Certification of Origin (DCO)</a><ul>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#overview">Overview</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#accepted-licenses-and-copyright-notices">Accepted licenses and copyright notices</a><ul>
<li class="toctree-l4"><a class="reference internal" href="CONTRIBUTING.html#your-own-work">Your own work</a></li>
<li class="toctree-l4"><a class="reference internal" href="CONTRIBUTING.html#use-code-from-online-source">Use code from online source</a></li>
<li class="toctree-l4"><a class="reference internal" href="CONTRIBUTING.html#use-mit-licensed-code">Use MIT licensed code</a></li>
<li class="toctree-l4"><a class="reference internal" href="CONTRIBUTING.html#use-gpl-licensed-code">Use GPL licensed code</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="CONTRIBUTING.html#ways-to-contribute">Ways to contribute</a><ul>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#give-lvgl-a-star">Give LVGL a Star</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#tell-what-you-have-achieved">Tell what you have achieved</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#write-examples">Write examples</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#improve-the-docs">Improve the docs</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#report-bugs">Report bugs</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#send-fixes">Send fixes</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#join-the-conversations-in-the-forum">Join the conversations in the Forum</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#add-features">Add features</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#become-a-maintainer">Become a maintainer</a></li>
<li class="toctree-l3"><a class="reference internal" href="CONTRIBUTING.html#move-your-project-repository-under-lvgl-organization">Move your project repository under LVGL organization</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="CHANGELOG.html">Changelog</a><ul>
<li class="toctree-l2"><a class="reference internal" href="CHANGELOG.html#v8-0-2-16-07-2021">v8.0.2 (16.07.2021)</a></li>
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  <div class="section" id="coding-style">
<h1>Coding style<a class="headerlink" href="#coding-style" title="Permalink to this headline">¶</a></h1>
<div class="section" id="file-format">
<h2>File format<a class="headerlink" href="#file-format" title="Permalink to this headline">¶</a></h2>
<p>Use <a class="reference external" href="https://github.com/lvgl/lvgl/blob/master/src/misc/lv_templ.c">misc/lv_templ.c</a> and <a class="reference external" href="https://github.com/lvgl/lvgl/blob/master/src/misc/lv_templ.h">misc/lv_templ.h</a></p>
</div>
<div class="section" id="naming-conventions">
<h2>Naming conventions<a class="headerlink" href="#naming-conventions" title="Permalink to this headline">¶</a></h2>
<ul class="simple">
<li><p>Words are separated by '_'</p></li>
<li><p>In variable and function names use only lower case letters (e.g. <em>height_tmp</em>)</p></li>
<li><p>In enums and defines use only upper case letters (e.g. <em>e.g. MAX_LINE_NUM</em>)</p></li>
<li><p>Global names (API):</p>
<ul>
<li><p>start with <em>lv</em></p></li>
<li><p>followed by module name: <em>btn</em>, <em>label</em>, <em>style</em> etc.</p></li>
<li><p>followed by the action (for functions): <em>set</em>, <em>get</em>, <em>refr</em> etc.</p></li>
<li><p>closed with the subject: <em>name</em>, <em>size</em>, <em>state</em> etc.</p></li>
</ul>
</li>
<li><p>Typedefs</p>
<ul>
<li><p>prefer <code class="docutils literal notranslate"><span class="pre">typedef</span> <span class="pre">struct</span></code> and <code class="docutils literal notranslate"><span class="pre">typedef</span> <span class="pre">enum</span></code> instead of  <code class="docutils literal notranslate"><span class="pre">struct</span> <span class="pre">name</span></code> and <code class="docutils literal notranslate"><span class="pre">enum</span> <span class="pre">name</span></code></p></li>
<li><p>always end <code class="docutils literal notranslate"><span class="pre">typedef</span> <span class="pre">struct</span></code> and <code class="docutils literal notranslate"><span class="pre">typedef</span> <span class="pre">enum</span></code> type names with <code class="docutils literal notranslate"><span class="pre">_t</span></code></p></li>
</ul>
</li>
<li><p>Abbreviations:</p>
<ul>
<li><p>Only words longer or equal than 6 characters can be abbreviated.</p></li>
<li><p>Abbreviate only if it makes the word at least half as long</p></li>
<li><p>Use only very straightforward and well-known abbreviations (e.g. pos: position, def: default, btn: button)</p></li>
</ul>
</li>
</ul>
</div>
<div class="section" id="coding-guide">
<h2>Coding guide<a class="headerlink" href="#coding-guide" title="Permalink to this headline">¶</a></h2>
<ul class="simple">
<li><p>Functions:</p>
<ul>
<li><p>Try to write function shorter than is 50 lines</p></li>
<li><p>Always shorter than 200 lines (except very straightforwards)</p></li>
</ul>
</li>
<li><p>Variables:</p>
<ul>
<li><p>One line, one declaration (BAD: char x, y;)</p></li>
<li><p>Use <code class="docutils literal notranslate"><span class="pre">&lt;stdint.h&gt;</span></code> (<em>uint8_t</em>, <em>int32_t</em> etc)</p></li>
<li><p>Declare variables where needed (not all at function start)</p></li>
<li><p>Use the smallest required scope</p></li>
<li><p>Variables in a file (outside functions) are always <em>static</em></p></li>
<li><p>Do not use global variables (use functions to set/get static variables)</p></li>
</ul>
</li>
</ul>
</div>
<div class="section" id="comments">
<h2>Comments<a class="headerlink" href="#comments" title="Permalink to this headline">¶</a></h2>
<p>Before every function have a comment like this:</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="cm">/**</span>
<span class="cm"> * Return with the screen of an object</span>
<span class="cm"> * @param obj pointer to an object</span>
<span class="cm"> * @return pointer to a screen</span>
<span class="cm"> */</span>
<span class="n">lv_obj_t</span> <span class="o">*</span> <span class="nf">lv_obj_get_scr</span><span class="p">(</span><span class="n">lv_obj_t</span> <span class="o">*</span> <span class="n">obj</span><span class="p">);</span>
</pre></div>
</div>
<p>Always use <code class="docutils literal notranslate"><span class="pre">/*Something*/</span></code> format and NOT <code class="docutils literal notranslate"><span class="pre">//Something</span></code></p>
<p>Write readable code to avoid descriptive comments like:
<code class="docutils literal notranslate"><span class="pre">x++;</span> <span class="pre">/*Add</span> <span class="pre">1</span> <span class="pre">to</span> <span class="pre">x*/</span></code>.
The code should show clearly what you are doing.</p>
<p>You should write <strong>why</strong> have you done this:
<code class="docutils literal notranslate"><span class="pre">x++;</span> <span class="pre">/*Because</span> <span class="pre">of</span> <span class="pre">closing</span> <span class="pre">'\0'</span> <span class="pre">of</span> <span class="pre">the</span> <span class="pre">string*/</span></code></p>
<p>Short &quot;code summaries&quot; of a few lines are accepted. E.g. <code class="docutils literal notranslate"><span class="pre">/*Calculate</span> <span class="pre">the</span> <span class="pre">new</span> <span class="pre">coordinates*/</span></code></p>
<p>In comments use ` ` when referring to a variable. E.g. <code class="docutils literal notranslate"><span class="pre">/*Update</span> <span class="pre">the</span> <span class="pre">value</span> <span class="pre">of</span> <span class="pre">`x_act`*/</span></code></p>
<div class="section" id="formatting">
<h3>Formatting<a class="headerlink" href="#formatting" title="Permalink to this headline">¶</a></h3>
<p>Here is example to show bracket placing and using of white spaces:</p>
<div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="cm">/**</span>
<span class="cm"> * Set a new text for a label. Memory will be allocated to store the text by the label.</span>
<span class="cm"> * @param label pointer to a label object</span>
<span class="cm"> * @param text &#39;\0&#39; terminated character string. NULL to refresh with the current text.</span>
<span class="cm"> */</span>
<span class="kt">void</span> <span class="nf">lv_label_set_text</span><span class="p">(</span><span class="n">lv_obj_t</span> <span class="o">*</span> <span class="n">label</span><span class="p">,</span> <span class="k">const</span> <span class="kt">char</span> <span class="o">*</span> <span class="n">text</span><span class="p">)</span>
<span class="p">{</span>   <span class="cm">/*Main brackets of functions in new line*/</span>

    <span class="k">if</span><span class="p">(</span><span class="n">label</span> <span class="o">==</span> <span class="nb">NULL</span><span class="p">)</span> <span class="k">return</span><span class="p">;</span> <span class="cm">/*No bracket only if the command is inline with the if statement*/</span>

    <span class="n">lv_obj_inv</span><span class="p">(</span><span class="n">label</span><span class="p">);</span>

    <span class="n">lv_label_ext_t</span> <span class="o">*</span> <span class="n">ext</span> <span class="o">=</span> <span class="n">lv_obj_get_ext</span><span class="p">(</span><span class="n">label</span><span class="p">);</span>

    <span class="cm">/*Comment before a section*/</span>
    <span class="k">if</span><span class="p">(</span><span class="n">text</span> <span class="o">==</span> <span class="n">ext</span><span class="o">-&gt;</span><span class="n">txt</span> <span class="o">||</span> <span class="n">text</span> <span class="o">==</span> <span class="nb">NULL</span><span class="p">)</span> <span class="p">{</span>  <span class="cm">/*Bracket of statements start inline*/</span>
        <span class="n">lv_label_refr_text</span><span class="p">(</span><span class="n">label</span><span class="p">);</span>
        <span class="k">return</span><span class="p">;</span>
    <span class="p">}</span>

    <span class="p">...</span>
<span class="p">}</span>
</pre></div>
</div>
<p>Use 4 spaces indentation instead of tab.</p>
<p>You can use <strong>astyle</strong> to format the code. Run <code class="docutils literal notranslate"><span class="pre">code-formatter.sh</span></code> from the <code class="docutils literal notranslate"><span class="pre">scrips</span></code> folder.</p>
</div>
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