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RadioButton.md

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Selection controls: radio buttons

Selection controls allow the user to select options.

Use radio buttons to:

  • Select a single option from a list
  • Expose all available options
  • If available options can be collapsed, consider using a dropdown menu instead, as it uses less space.

Settings menu with radio buttons for ringtones

Contents

Design & API Documentation

Using radio buttons

Before you can use Material radio buttons, you need to add a dependency to the Material Components for Android library. For more information, go to the Getting started page.

Note: <RadioButton> is auto-inflated as <com.google.android.material.button.MaterialRadioButton> via MaterialComponentsViewInflater when using a Theme.Material3.* theme.

Making radio buttons accessible

Radio buttons support content labeling for accessibility and are readable by most screen readers, such as TalkBack. Text rendered in radio buttons is automatically provided to accessibility services. Additional content labels are usually unnecessary.

Grouping radio buttons

Changes in the states of one radio button can affect other buttons in the group. Specifically, selecting a RadioButton in a RadioGroup will de-select all other buttons in that group. See the example section below for implementation details.

Radio button

A radio button is a circle that is filled in with an inset when selected. Radio buttons allow the user to select one option from a set. Use radio buttons when the user needs to see all available options. If available options can be collapsed, consider using a dropdown menu because it uses less space.

API and source code:

Radio buttons example

The following example shows a radio button group with five radio buttons.

Example radio button group with 5 radio buttons, the first one is selected and the last one is disabled.

In the layout:

<RadioGroup
    android:id="@+id/radioGroup"
    android:checkedButton="@+id/radio_button_1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    <RadioButton
        android:id="@+id/radio_button_1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="@string/label_1"/>
    <RadioButton
        android:id="@+id/radio_button_2"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="@string/label_2"/>
    <RadioButton
        android:id="@+id/radio_button_3"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="@string/label_3"/>
    <RadioButton
        android:id="@+id/radio_button_4"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="@string/label_4"/>
    <RadioButton
        android:id="@+id/radio_button_5"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:enabled="false"
        android:text="@string/label_5"/>
</RadioGroup>

In code:

val checkedRadioButtonId = radioGroup.checkedRadioButtonId // Returns View.NO_ID if nothing is checked.
radioGroup.setOnCheckedChangeListener { group, checkedId ->
    // Responds to child RadioButton checked/unchecked
}

// To check a radio button
radioButton.isChecked = true

// To listen for a radio button's checked/unchecked state changes
radioButton.setOnCheckedChangeListener { buttonView, isChecked
    // Responds to radio button being checked/unchecked
}

Key properties

Radio button attributes

Element Attribute Related method(s) Default value
To use material colors app:useMaterialThemeColors setUseMaterialThemeColors
isUseMaterialThemeColors
true (ignored if app:buttonTint is set)
Color app:buttonTint setButtonTintList
getButtonTintList
?attr/colorOnSurface (see all states)
Min size android:minWidth
android:minHeight
(set/get)MinWidth
(set/get)MinHeight
?attr/minTouchTargetSize

The color of the radio button defaults to ?attr/colorOnSurface (unchecked) and ?attr/colorPrimary (checked) defined in your app theme. If you want to override this behavior, you could use a custom drawable that should not be tinted, set app:useMaterialThemeColors to false:

<RadioButton
    ...
    app:useMaterialThemeColors="false"
/>

Text label attributes

Element Attribute Related method(s) Default value
Text label android:text setText
getText
null
Color android:textColor setTextColor
getTextColors
inherits from AppCompatRadioButton
Typography android:textAppearance setTextAppearance ?attr/textAppearanceBodyMedium

Radio button states

Radio buttons can be selected or unselected. Radio buttons have enabled, disabled, hover, focused, and pressed states.

Radio button states in an array. Columns are enabled, disabled, hover, focused, pressed. Rows are selected or unselected

Styles

Element Style
Default style Widget.Material3.CompoundButton.RadioButton

Default style theme attribute: ?attr/radioButtonStyle

See the full list of styles and attrs.

Theming radio buttons

Radio buttons support Material Theming which can customize color and typography.

Radio button theming example

API and source code:

The following example shows a radio button with Material Theming.

"5 radio buttons with brown text; first selected with pink outline and fill, last disabled with light brown text and button"

Implementing radio button theming

Use theme attributes in res/values/styles.xml which applies to all radio buttons and affects other components:

<style name="Theme.App" parent="Theme.Material3.*">
    ...
    <item name="colorOnSurface">@color/shrine_pink_900</item>
    <item name="colorPrimary">@color/shrine_pink_100</item>
</style>

Use default style theme attributes, styles and theme overlays which apply to all radio buttons but do not affect other components:

<style name="Theme.App" parent="Theme.Material3.*">
    ...
    <item name="radioButtonStyle">@style/Widget.App.RadioButton</item>
</style>

<style name="Widget.App.RadioButton" parent="Widget.Material3.CompoundButton.RadioButton">
    <item name="materialThemeOverlay">@style/ThemeOverlay.App.RadioButton</item>
</style>

<style name="ThemeOverlay.App.RadioButton" parent="">
    <item name="colorOnSurface">@color/shrine_pink_900</item>
    <item name="colorPrimary">@color/shrine_pink_100</item>
</style>

You can also change the radio button colors via the ?attr/buttonTint attribute:

<style name="Widget.App.RadioButton" parent="Widget.Material3.CompoundButton.RadioButton">
    <item name="buttonTint">@color/button_tint</item>
</style>

and in color/button_tint.xml:

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/shrine_pink_900" android:state_checked="true"/>
    <item android:alpha="0.38" android:color="@color/shrine_pink_100" android:state_enabled="false"/>
    <item android:color="@color/shrine_pink_100"/>
</selector>

You can use the styles in the layout, which affects only this radio button:

<RadioButton
    ...
    style="@style/Widget.App.RadioButton"
/>