# Selection controls: checkboxes
[Selection controls](https://material.io/components/selection-controls#usage)
allow the user to select options.
Use checkboxes to:
* Select one or more options from a list
* Present a list containing sub-selections
* Turn an item on or off in a desktop environment
**Contents**
* [Design & API Documentation](#design-api-documentation)
* [Using checkboxes](#using-checkboxes)
* [Checkbox](#checkbox)
* [Theming checkboxes](#theming-checkboxes)
## Design & API Documentation
* [Google Material3 Spec](https://material.io/components/checkbox/overview)
* [API reference](https://developer.android.com/reference/com/google/android/material/checkbox/package-summary)
## Using checkboxes
Before you can use Material checkboxes, you need to add a dependency to the
Material Components for Android library. For more information, go to the
[Getting started](https://github.com/material-components/material-components-android/tree/master/docs/getting-started.md)
page.
```xml
```
**Note:** `` is auto-inflated as
`` via
`MaterialComponentsViewInflater` when using a `Theme.Material3.*`
theme.
### Making checkboxes accessible
Checkboxes support content labeling for accessibility and are readable by most
screen readers, such as TalkBack. Text rendered in check boxes is automatically
provided to accessibility services. Additional content labels are usually
unnecessary.
### Checking a checkbox
In the layout:
```xml
```
In code:
```kt
// To check a checkbox
checkbox.isChecked = true
// To listen for a checkbox's checked/unchecked state changes
checkbox.setOnCheckedChangeListener { buttonView, isChecked ->
// Responds to checkbox being checked/unchecked
}
// Alternatively, you can check a checkbox via setCheckedState
checkBox.setCheckedState(MaterialCheckbox.STATE_CHECKED);
// To uncheck:
checkBox.setCheckedState(MaterialCheckbox.STATE_UNCHECKED);
// And to listen for changes:
checkbox.addOnCheckedStateChangedListener { checkBox, state ->
// Responds to when the checkbox changes state.
}
```
### Setting the error state on checkbox
In the layout:
```xml
```
In code:
```kt
// Set error.
checkbox.errorShown = true
// Optional listener:
checkbox.addOnErrorChangedListener { checkBox, errorShown ->
// Responds to when the checkbox enters/leaves error state
}
// To set a custom accessibility label:
checkbox.errorAccessibilityLabel = "Error: custom error announcement."
```
### Making a checkbox indeterminate
In the layout:
```xml
```
In code:
```kt
// You can set the state of the checkbox (STATE_CHECKED, STATE_UNCHECKED,
// or STATE_INDETERMINATE) via setCheckedState.
checkBox.setCheckedState(MaterialCheckbox.STATE_INDETERMINATE);
// Checkbox state listener.
checkbox.addOnCheckedStateChangedListener { checkBox, state ->
// Responds to when the checkbox changes state.
}
```
## Checkbox
A checkbox is a square button with a check to denote its current state.
Checkboxes allow the user to select one or more items from a set. Checkboxes can
be used to turn an option on or off. Unlike radio buttons, changes in the states
of one checkbox do not usually affect other checkboxes.
**Note:** Checkboxes do not support shape theming and are only rounded square
checkboxes.
### Checkboxes example
API and source code:
* `MaterialCheckBox`
* [Class definition](https://developer.android.com/reference/com/google/android/material/checkbox/MaterialCheckBox)
* [Class source](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/MaterialCheckBox.java)
The following example shows a list of checkboxes with a parent/children
relationship.
The first checkbox (the parent) will be checked if all children are checked,
unchecked if all of the children are unchecked, and indeterminate if only some
of the children are checked.
In the layout:
```xml
```
In code:
```kt
// Class variable
private var isUpdatingChildren = false
...
// Parent's checked state changed listener
val parentOnCheckedStateChangedListener =
OnCheckedStateChangedListener { checkBox: MaterialCheckBox, state: Int ->
val isChecked = checkBox.isChecked
if (state != MaterialCheckBox.STATE_INDETERMINATE) {
isUpdatingChildren = true
for (child in childrenCheckBoxes) {
child.isChecked = isChecked
}
isUpdatingChildren = false
}
}
checkBoxParent.addOnCheckedStateChangedListener(parentOnCheckedStateChangedListener)
// Checked state changed listener for each child
val childOnCheckedStateChangedListener =
OnCheckedStateChangedListener { checkBox: MaterialCheckBox?, state: Int ->
if (!isUpdatingChildren) {
setParentState(checkBoxParent, childrenCheckBoxes, parentOnCheckedStateChangedListener)
}
}
for (child in childrenCheckBoxes) {
(child as MaterialCheckBox)
.addOnCheckedStateChangedListener(childOnCheckedStateChangedListener)
}
// Set first child to be checked
firstChild.isChecked = true
// Set parent's state
setParentState(checkBoxParent, childrenCheckBoxes, parentOnCheckedStateChangedListener)
...
private fun setParentState(
checkBoxParent: MaterialCheckBox,
childrenCheckBoxes: List,
parentOnCheckedStateChangedListener: OnCheckedStateChangedListener
) {
val checkedCount = childrenCheckBoxes.stream().filter { obj: CheckBox -> obj.isChecked }
.count()
.toInt()
val allChecked = checkedCount == childrenCheckBoxes.size
val noneChecked = checkedCount == 0
checkBoxParent.removeOnCheckedStateChangedListener(parentOnCheckedStateChangedListener)
if (allChecked) {
checkBoxParent.isChecked = true
} else if (noneChecked) {
checkBoxParent.isChecked = false
} else {
checkBoxParent.checkedState = MaterialCheckBox.STATE_INDETERMINATE
}
checkBoxParent.addOnCheckedStateChangedListener(parentOnCheckedStateChangedListener)
}
```
## Anatomy and key properties
The following is an anatomy diagram that shows a checkbox container and icon:
1. Container
2. Icon
### Checkbox attributes
The checkbox is composed of an `app:buttonCompat` drawable (the container) and
an `app:buttonIcon` drawable (the icon) layered on top of it.
Element | Attribute | Related method(s) | Default value
-------------------------- | ------------------------------------------ | ---------------------------------------------------------- | -------------
**Button tint** | `app:buttonTint` | `setButtonTintList`
`getButtonTintList` | `?attr/colorOnSurface` (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/res/color/m3_checkbox_button_tint.xml))
**Button icon drawable** | `app:buttonIcon` | `setButtonIconDrawable`
`getButtonIconDrawable` | [@mtrl_checkbox_button_icon](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/res/drawable/mtrl_checkbox_button_icon.xml)
**Button icon tint** | `app:buttonIconTint` | `setButtonIconTintList`
`getButtonIconTintList` | `?attr/colorOnPrimary` (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/res/color/m3_checkbox_button_icon_tint.xml))
**Min size** | `android:minWidth`
`android:minHeight` | `(set/get)MinWidth`
`(set/get)MinHeight` | `?attr/minTouchTargetSize`
**Centered icon if no text** | `app:centerIfNoTextEnabled` | `setCenterIfNoTextEnabled`
`isCenterIfNoTextEnabled` | `true`
**Note:** If setting a custom `app:buttonCompat`, make sure to also set
`app:buttonIcon` if an icon is desired. The checkbox does not support having a
custom `app:buttonCompat` and preserving the default `app:buttonIcon` checkmark
at the same time.
### Text label attributes
Element | Attribute | Related method(s) | Default value
-------------- | ------------------------ | ---------------------------------- | -------------
**Text label** | `android:text` | `setText`
`getText` | `null`
**Color** | `android:textColor` | `setTextColor`
`getTextColors` | inherits from `AppCompatCheckBox`
**Typography** | `android:textAppearance` | `setTextAppearance` | `?attr/textAppearanceBodyMedium`
### Checkbox states
Checkboxes can be selected, unselected, or indeterminate, and those states on
error. Checkboxes have enabled, disabled, hover, focused, and pressed states.
1. Enabled
2. Disabled
3. Hover
4. Focused
5. Pressed
### Styles
Element | Style
----------------- | ---------------------------------------------------
**Default style** | `Widget.Material3.CompoundButton.CheckBox`
Default style theme attribute: `?attr/checkboxStyle`
See the full list of
[styles](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/res/values/styles.xml)
and
[attrs](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/res/values/attrs.xml).
## Theming checkboxes
Checkboxes support
[Material Theming](https://material.io/components/selection-controls#theming)
which can customize color and typography.
### Checkbox theming example
API and source code:
* `MaterialCheckBox`
* [Class definition](https://developer.android.com/reference/com/google/android/material/checkbox/MaterialCheckBox)
* [Class source](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/checkbox/MaterialCheckBox.java)
The following example shows a checkbox with Material Theming.
#### Implementing checkbox theming
Use theme attributes in `res/values/styles.xml`, which adds a theme to all
checkboxes and affects other components:
```xml
```
Use default style theme attributes, styles and theme overlays, which will add a
theme to all checkboxes but does not affect other components:
```xml
```
You can also change the checkbox colors via the `?attr/buttonTint` and
`?attr/buttonIconTint` attributes:
```xml
```
in `color/button_tint.xml`:
```xml