2018-03-12 12:40:36 -04:00

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<!--docs:
title: "Chips"
layout: detail
section: components
excerpt: "Chips represent complex entities in small blocks, such as a contact."
iconId: chip
path: /catalog/chip/
-->
# Chips
A `Chip` represents a complex entity in a small block, such as a contact. It is
a rounded button that consists of a label, an optional chip icon, and an
optional close icon. A chip can either be clicked or toggled if it is checkable.
Chips may be placed in a `ChipGroup`, which can be configured to lay out its
chips in a single horizontal line or reflowed across multiple lines. If a chip
group contains checkable chips, it can also control the multiple-exclusion scope
for its set of chips so that checking one chip unchecks all other chips in the
group.
You can also directly use a standalone `ChipDrawable` in contexts that require a
Drawable. For example, an auto-complete enabled text field can replace snippets
of text with a `ChipDrawable` using a span to represent it as a semantic entity.
## Design & API Documentation
- [Material Design guidelines:
Chips](https://material.io/guidelines/components/chips.html)
<!--{: .icon-list-item.icon-list-item--spec }-->
- [Class
definition](https://github.com/material-components/material-components-android/tree/master/lib/java/android/support/design/chip/Chip.java)
<!--{: .icon-list-item.icon-list-item--link }-->
## Usage
The `Chip` widget provides a complete implementation of Material Design's chip
component. Example code of how to include the widget in your layout:
```xml
<android.support.design.chip.Chip
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipText="@string/hello_world"/>
```
### Material Styles
Using `Chip` with an updated Material theme (`Theme.MaterialComponents`) will
provide the correct updated Material styles to your chips by default. If you
need to use an updated Material chip and your application theme does not inherit
from an updated Material theme, you can apply one of the updated Material styles
directly to your widget in XML.
#### Entry Chip
Use entry chips to represent a complex piece of information in a compact form.
This style usually contains an optional chip icon, optional close icon, and is
optionally checkable.
```xml
<android.support.design.chip.Chip
style="@style/Widget.MaterialComponents.Chip.Entry"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipIcon="@drawable/ic_avatar_circle_24"
app:chipText="@string/hello_world"/>
```
Note: Entry chips are usually used with a standalone `ChipDrawable`.
#### Filter Chip
Use filter chips containing tags or descriptive words to filter a collection.
This style usually contains an optional chip icon, an optional close icon, and
is always checkable.
```xml
<android.support.design.chip.Chip
style="@style/Widget.MaterialComponents.Chip.Filter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipText="@string/hello_world"/>
```
Note: Filter chips are usually placed within a `ChipGroup`.
#### Choice Chip
Use choice chips to help users make a single selection from a finite set of
options.
This style usually contains an optional chip icon and is always checkable.
```xml
<android.support.design.chip.Chip
style="@style/Widget.MaterialComponents.Chip.Choice"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipText="@string/hello_world"/>
```
Note: Choice chips are usually placed within a `ChipGroup`.
#### Action Chip (Default)
Use action chips to trigger an action that is contextual to primary content.
This style usually contains an optional chip icon and is never checkable.
```xml
<android.support.design.chip.Chip
style="@style/Widget.MaterialComponents.Chip.Action"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:chipIcon="@drawable/ic_action_24"
app:chipText="@string/hello_world"/>
```
### Chip Attributes
Feature | Relevant attributes
:----------- | :--------------------------
Shape | `app:chipCornerRadius`
Size | `app:chipMinHeight`
Background | `app:chipBackgroundColor`
Border | `app:chipStrokeColor`
| `app:chipStrokeWidth`
Ripple | `app:rippleColor`
Label | `app:chipText`
| `android:textAppearance`
Chip Icon | `app:chipIconEnabled`
| `app:chipIcon`
| `app:chipIconSize`
Close Icon | `app:closeIconEnabled`
| `app:closeIcon`
| `app:closeIconSize`
| `app:closeIconTint`
Checkable | `app:checkable`
Checked Icon | `app:checkedIconEnabled`
| `app:checkedIcon`
Motion | `app:showMotionSpec`
| `app:hideMotionSpec`
Paddings | `app:chipStartPadding`
| `app:iconStartPadding`
| `app:iconEndPadding`
| `app:textStartPadding`
| `app:textEndPadding`
| `app:closeIconStartPadding`
| `app:closeIconEndPadding`
| `app:chipEndPadding`
### Handling Clicks
Call `setOnClickListener(OnClickListener)` to register a callback to be invoked
when the chip is clicked.
```java
Chip chip = (Chip) findViewById(R.id.chip);
chip.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View view) {
// Handle the click.
}
});
```
Or, call `setOnCheckedChangeListener(OnCheckedChangeListener)` to register a
callback to be invoked when the chip is toggled.
```java
Chip chip = (Chip) findViewById(R.id.chip);
chip.setOnCheckedChangeListener(new setOnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton view, boolean isChecked) {
// Handle the toggle.
}
});
```
Call `setOnCloseIconClickListener(OnClickListener)` to register a callback to be
invoked when the chip's close icon is clicked.
```java
Chip chip = (Chip) findViewById(R.id.chip);
chip.setOnCloseIconClickListener(new OnClickListener() {
@Override
public void onClick(View view) {
// Handle the click on the close icon.
}
});
```
### ChipGroup
A `ChipGroup` contains a set of `Chip`s and manages their layout and
multiple-exclusion scope, similarly to a `RadioGroup`.
#### Layout Mode
A `ChipGroup` will by default reflow its chips across multiple lines.
```xml
<android.support.design.chip.ChipGroup
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!-- Chips can be declared here, or added dynamically. -->
</android.support.design.chip.ChipGroup>
```
A `ChipGroup` can also constrain its chips to a single horizontal line using the
`app:singleLine` attribute. If you do so, you'll usually want to wrap the
`ChipGroup` in a `HorizontalScrollView`.
```xml
<HorizontalScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.design.chip.ChipGroup
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:singleLine="true">
<!-- Chips can be declared here, or added dynamically. -->
</android.support.design.chip.ChipGroup>
</HorizontalScrollView>
```
#### Multiple Exclusion Scope
A `ChipGroup` can be configured to only allow a single chip to be checked at a
time using the `app:singleSelection` attribute.
```xml
<android.support.design.chip.ChipGroup
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:singleSelection="true">
<!-- ... -->
</android.support.design.chip.ChipGroup>
```
#### Handling Checked Chips
Call `setOnCheckedChangeListener(OnCheckedChangeListener)` to register a
callback to be invoked when the checked chip changes in this group. This
callback is only invoked in single selection mode.
```java
ChipGroup chipGroup = (ChipGroup) findViewById(R.id.chip_group);
chipGroup.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(ChipGroup group, @IdRes int checkedId) {
// Handle the checked chip change.
}
});
```
Or, call `getCheckedChipId()` at any time to get the checked chip. The return
value is only valid in single selection mode.
### Standalone ChipDrawable
A standalone `ChipDrawable` can be used in contexts that require a `Drawable`.
The most obvious use case is in text fields that "chipify" contacts, commonly
found in communications apps.
To use a `ChipDrawable`, first create a chip resource in `res/xml`.
**res/xml/standalone_chip.xml**
```xml
<chip
xmlns:app="http://schemas.android.com/apk/res-auto"
app:chipIcon="@drawable/ic_avatar_circle_24"
app:chipText="@string/hello_world"/>
```
After inflating it dynamically, you can treat it as any other `Drawable`.
**MainActivity.java**
```java
// Inflate from resources.
ChipDrawable chip = ChipDrawable.createFromResource(getContext(), R.xml.standalone_chip);
// Use it as a Drawable however you want.
chip.setBounds(0, 0, chip.getIntrinsicWidth(), chip.getIntrinsicHeight());
ImageSpan span = new ImageSpan(chip);
Editable text = editText.getText();
text.setSpan(span, 0, text.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
```
#### Styles
Entry Chip is the default Material style for standalone `ChipDrawable`s, but you
can apply any of the other styles using a `style` attribute.
```xml
<chip
xmlns:app="http://schemas.android.com/apk/res-auto"
style="@style/Widget.MaterialComponents.Chip.Filter"
app:chipIcon="@drawable/ic_avatar_circle_24"
app:chipText="@string/hello_world"/>
```
#### Attributes
All the attributes on `Chip` can be applied to a `ChipDrawable` resource.