ExpandableCheckbox

An expandable checkbox for Android which can contain child checkboxes.

Note that the gif below has custom values set for colors.

Known Issues

1. ChildTextColor does not show properly in XML preview
2. ExpanderColor does not show properly on children in XML preview

Add it to your project

1. Use the "Clone or Download" button above to download a zip of the source files
2. Extract the "expandablecheckbox" folder into your project folder
3. Add the following line to your settings.gradle file: include ':app', ':expandablecheckbox' where "app" is the name of your app module
   1. If you already have other modules, just add , ':expandablecheckbox' to the existing list
   2. If you don't currently have a settings.gradle file, add it to the base directory of your project (where your project-wide build.gradle is)
4. In your app's build.gradle, add the following:

   dependencies {
       implementation project(path: ':expandablecheckbox')
   }
   

The source code files that you downloaded in step 1 above include a fully working test app, so look at how those files are structured if you aren't sure how to do it.

How it works

Checkboxes can be used from Java/Kotlin code, from XML code, or a combination of both.

Clicking on the parent checkbox will check or uncheck all of the children beneath it, selecting all of the children will check the parent, deselecting all of the children will deselect the parent, and selecting some of the children (but not all) will put the parent in an in between state where it shows as fully filled in, instead of having a check mark or being completely empty.

Clicking on the expander [+] or [-] will expand or collapse the child view.

Long pressing the text of the parent checkbox will also expand or collapse the child view.

Optional XML parameters

checked: Initial value of the checkbox. If true the box wil be checked, if false it will be empty (unchecked).

Default: False

expanded: The initial state of the child view. If true, the children will be shown, if false they will be hidden.

Default: False

text: The text shown next to the parent checkbox

Default: "" (empty String)

textColor: The color of the text shown next to the parent checkbox

Default: android.R.attr.textColorPrimary. If android.R.attr.textColorPrimary not found, default is Color.Black

childTextColor: The color of the text shown next to the child checkboxes

Default: android.R.attr.textColorPrimary. If android.R.attr.textColorPrimary not found, default is Color.Black

checkboxColor: The color of the box containing the parent checkbox

Default: For API 21+ - android.R.attr.colorPrimary. If android.R.attr.colorPrimary not found, or API is < 21, default is default text color

childCheckboxColor: The color of the box containing the child checkboxes

Default: For API 21+ - android.R.attr.colorPrimary. If android.R.attr.colorPrimary not found, or API is < 21, default is default text color

expanderColor: The color of the [+] or [-] drawable used to expand/collapse the child view NOTE: Changing this color will also change the color of expanders in child objects. You can explicitly change the color of the expander on those children, and the color set on the child object will take priority.

Default: Default text color

Kotlin example

// Create Expandable Checkbox
val expandableCheckbox = ExpandableCheckbox(context)

// Add a child checkbox. This can be repeated to add multiple children
expandableCheckbox.addChild("child checkbox", object : CompoundButton.OnCheckedChangeListener{
    override fun onCheckedChanged(buttonView: CompoundButton?, isChecked: Boolean) {
        if (isChecked)
            // Do something when checked
        else
            // Do something when unchecked
    }
}

// Add an existing child
val child2 = ExpandableCheckbox(this)
child2.text = "Top"
child2.textColor = Color.RED
child2.childTextColor = Color.CYAN
child2.childCheckboxColor = Color.MAGENTA

expandableCheckbox.addChild(child2)

// Children can also have children
child2.addChild("Sub Child", null)

// Optional values
expandableCheckbox.expanded = true
expandableCheckbox.text = "Parent checkbox text"
expandableCheckbox.textColor = Color.WHITE
expandableCheckbox.childTextColor = Color.GREEN
expandableCheckbox.checkboxColor = Color.MAGENTA
expandableCheckbox.childCheckboxColor = Color.BLUE
expandableCheckbox.expanderColor = Color.YELLOW

XML Example

Most of the time when using XML, you will also have some Java or Kotlin code with it. Below is an example using both Kotlin and XML

XML Part

<com.fifteen15studios.expandablecheckbox.ExpandableCheckbox
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/parentCheckbox"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:text="ParentCheckbox"
    app:textColor="@color/white"
    app:childTextColor="@color/green"
    app:checkboxColor="@color/majenta"
    app:childCheckboxColor="@color/blue"
    app:expanderColor="@color/yellow">
    <!-- Any of the above values that start with "app:" are optional -->
    
    <!-- Children can be CheckBox or ExpandableCheckbox. The code will convert them all to ExpandableCheckbox -->
    <CheckBox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="childCheckbox"
        android:id="@+id/childCheckbox"/>
    <com.fifteen15studios.expandablecheckbox.ExpandableCheckbox
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/Child2"
        app:text="Child2"
        app:checkboxColor="@color/red"/>
</com.fifteen15studios.expandablecheckbox.ExpandableCheckbox>

Kotlin Part

val expandableCheckbox = findViewById<ExpandableCheckbox>(R.id.parentCheckbox)
val child1 = findViewById<Checkbox>(R.id.childCheckbox)

child1.setOnCheckedChangeListener(object : CompoundButton.OnCheckedChangeListener {
  override fun onCheckedChanged(buttonView: CompoundButton?, isChecked: Boolean) {
      if (isChecked)
          // Do something when checked
      else
          // Do something when unchecked
  }
})

Pubic functions

addChild(child: ExpandableCheckbox) - Adds a new child checkbox. Parameters: child: the checkbox to add

addChild(child: ExpandableCheckbox, onCheckedChangeListener: CompoundButton.OnCheckedChangeListener?) - Adds a new child checkbox. Parameters: child: the checkbox to add. onCheckedChangeListener: Actions to perform when the check changes for this child.

addChild(text : String, onCheckedChangeListener: CompoundButton.OnCheckedChangeListener?) - Adds a new child checkbox. Parameters: text: The text to display next to the child checkbox. onCheckedChangeListener: Actions to perform when the check changes for this child.

getChildCheckbox(text: String) - Returns the child checkbox with specific text value. Parameters: text: String to look for in each child

getChildCheckboxAt(index: Int) - Returns the child checkbox at a specific index. If the index is invalid, returns null. Parameters: index: Index at which to look for a child.

getChildCheckboxCount() - Returns the number of child checkboxes

hasChildren() - Returns true if it has child checkboxes, otherwise returns false

isChecked() - Returns true if parent is checked, false if parent is not checked.

isChecked(index: Int) - Returns true if child checkbox is checked, false if child checkbox is not checked. Parameters: index: index of child to check.

isExpanded() - Returns true if the view is currently expanded, false if it is currently collapsed

setAllChecked(checked : Boolean) - Checks or unchecks all checkboxes, parent and children. Parameters: checked: If true checks the parent and all children, if false unchecks the parent and all children.

setChecked(checked: Boolean) - Checks or unchecks the parent checkbox and ONLY the parent checkbox. Calling this function will NOT affect the children. Parameter: If true checks the parent, if False unchecks the parent.

setOnCheckedChangeListener(onCheckedChangeListener: CompoundButton.OnCheckedChangeListener?) - Sets the onCheckedChangeListener for this checkbox. Parameters: onCheckedChangeListener: Actions to perform when the check changes for this checkbox.