Add nested select

examples/reference/widgets/NestedSelect.ipynb

@@ -0,0 +1,254 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import panel as pn\n",
+    "pn.extension()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Discover more on using widgets to add interactivity to your applications in the [how-to guides on interactivity](../how_to/interactivity/index.md). Alternatively, learn [how to set up callbacks and (JS-)links between parameters](../../how_to/links/index.md) or [how to use them as part of declarative UIs with Param](../../how_to/param/index.html).\n",
+    "\n",
+    "#### Parameters:\n",
+    "\n",
+    "For details on other options for customizing the component see the [layout](../../how_to/layout/index.md) and [styling](../../how_to/styling/index.md) how-to guides.\n",
+    "\n",
+    "##### Core\n",
+    "\n",
+    "* **``options``** (dict): The options to select from. The options may be nested dictionaries or lists.\n",
+    "* **``value``** (dict): The value from all the Select widgets; the keys are the levels names. If no levels names are specified, the keys are the levels indices.\n",
+    "* **``levels``** (list): Either a list of strings or a list of dictionaries. If a list of strings, the strings are used as the names of the levels. If a list of dictionaries, each dictionary may have a \"name\" key, which is used as the name of the level, a \"type\" key, which is used as the type of widget, and any corresponding widget keyword arguments.\n",
+    "\n",
+    "##### Display\n",
+    "\n",
+    "* **``disabled``** (boolean): Whether the widget is editable\n",
+    "* **``name``** (str): The title of the widget\n",
+    "\n",
+    "___"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select = pn.widgets.NestedSelect(\n",
+    "    options={\n",
+    "        \"GFS\": {\n",
+    "            \"0.25 deg\": [\"00Z\", \"06Z\", \"12Z\", \"18Z\"],\n",
+    "            \"0.5 deg\": [\"00Z\", \"12Z\"],\n",
+    "            \"1 deg\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "        \"NAME\": {\n",
+    "            \"12 km\": [\"00Z\", \"12Z\"],\n",
+    "            \"3 km\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "    },\n",
+    "    levels=[\"Model\", \"Resolution\", \"Initialization\"],\n",
+    ")\n",
+    "select"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Like most other widgets, ``NestedSelect`` has a value parameter that can be accessed or set:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select.value"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "If ``levels`` names are not set, the value is keyed off the level index."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select = pn.widgets.NestedSelect(\n",
+    "    options={\n",
+    "        \"GFS\": {\n",
+    "            \"0.25 deg\": [\"00Z\", \"06Z\", \"12Z\", \"18Z\"],\n",
+    "            \"0.5 deg\": [\"00Z\", \"12Z\"],\n",
+    "            \"1 deg\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "        \"NAME\": {\n",
+    "            \"12 km\": [\"00Z\", \"12Z\"],\n",
+    "            \"3 km\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "    },\n",
+    ")\n",
+    "select.value"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "You can also define the default value by providing a dict."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select = pn.widgets.NestedSelect(\n",
+    "    options={\n",
+    "        \"GFS\": {\n",
+    "            \"0.25 deg\": [\"00Z\", \"06Z\", \"12Z\", \"18Z\"],\n",
+    "            \"0.5 deg\": [\"00Z\", \"12Z\"],\n",
+    "            \"1 deg\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "        \"NAME\": {\n",
+    "            \"12 km\": [\"00Z\", \"12Z\"],\n",
+    "            \"3 km\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "    },\n",
+    "    value={\"Model\": \"NAME\", \"Resolution\": \"12 km\", \"Initialization\": \"12Z\"},\n",
+    "    levels=[\"Model\", \"Resolution\", \"Initialization\"],\n",
+    ")\n",
+    "select"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Not all keys of the value need to be specified, and the keys can be specified in any order."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select = pn.widgets.NestedSelect(\n",
+    "    options={\n",
+    "        \"GFS\": {\n",
+    "            \"0.25 deg\": [\"00Z\", \"06Z\", \"12Z\", \"18Z\"],\n",
+    "            \"0.5 deg\": [\"00Z\", \"12Z\"],\n",
+    "            \"1 deg\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "        \"NAME\": {\n",
+    "            \"12 km\": [\"00Z\", \"12Z\"],\n",
+    "            \"3 km\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "    },\n",
+    "    value={\"Initialization\": \"12Z\", \"Resolution\": \"0.5 deg\"},\n",
+    "    levels=[\"Model\", \"Resolution\", \"Initialization\"],\n",
+    ")\n",
+    "select"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "An incomplete definition of options can also be used. The corresponding subsequent widgets will be hidden."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select = pn.widgets.NestedSelect(\n",
+    "    options={\n",
+    "        \"NAME\": {},\n",
+    "        \"GFS\": {\n",
+    "            \"0.25 deg\": [\"00Z\", \"06Z\", \"12Z\", \"18Z\"],\n",
+    "            \"0.5 deg\": [\"00Z\", \"12Z\"],\n",
+    "            \"1 deg\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "    },\n",
+    "    levels=[\"Model\", \"Resolution\", \"Initialization\"],\n",
+    ")\n",
+    "select"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "The value for the hidden widgets will be `None`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select.value = {\"Model\": \"NAME\"}"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "`levels` also accepts a list of dicts, where each dict contains the type of widget and its corresponding kwargs."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "select = pn.widgets.NestedSelect(\n",
+    "    options={\n",
+    "        \"GFS\": {\n",
+    "            \"0.25 deg\": [\"00Z\", \"06Z\", \"12Z\", \"18Z\"],\n",
+    "            \"0.5 deg\": [\"00Z\", \"12Z\"],\n",
+    "            \"1 deg\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "        \"NAME\": {\n",
+    "            \"12 km\": [\"00Z\", \"12Z\"],\n",
+    "            \"3 km\": [\"00Z\", \"12Z\"],\n",
+    "        },\n",
+    "    },\n",
+    "    value={\"Model\": \"NAME\", \"Resolution\": \"12 km\", \"Initialization\": \"00Z\"},\n",
+    "    levels=[\n",
+    "        {\"name\": \"Model\", \"type\": pn.widgets.RadioButtonGroup, \"button_type\": \"primary\"},\n",
+    "        {\"name\": \"Resolution\", \"type\": pn.widgets.Select, \"width\": 100},\n",
+    "        {\"name\": \"Initialization\", \"type\": pn.widgets.DiscreteSlider, \"width\": 100},\n",
+    "    ],\n",
+    ")\n",
+    "select"
+   ]
+  }
+ ],
+ "metadata": {
+  "language_info": {
+   "name": "python",
+   "pygments_lexer": "ipython3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}