Slider
Sliders allow users to make selections from a range of values.
Contents
Using sliders
Before you can use Material sliders, you need to add a dependency to the Material Components for Android library. For more information, go to the Getting started page.
Usage
Add a Slider to a layout:
<!-- Continuous slider -->
<com.google.android.material.slider.Slider
    ...
    android:valueFrom="0.0"
    android:valueTo="100.0"  />
<!-- Discrete slider -->
<com.google.android.material.slider.Slider
    ...
    android:valueFrom="0.0"
    android:valueTo="100.0"
    android:stepSize="10.0"  />
Observe changes to a slider:
slider.addOnSliderTouchListener(object : Slider.OnSliderTouchListener {
    override fun onStartTrackingTouch(slider: Slider) {
        // Responds to when slider's touch event is being started
    }
    override fun onStopTrackingTouch(slider: Slider) {
        // Responds to when slider's touch event is being stopped
    }
})
slider.addOnChangeListener { slider, value, fromUser ->
    // Responds to when slider's value is changed
}
Add a RangeSlider to a layout:
<!-- Continuous slider -->
<com.google.android.material.slider.RangeSlider
    ...
    android:valueFrom="0.0"
    android:valueTo="100.0"
    app:values="@array/initial_slider_values"  />
<!-- Discrete slider -->
<com.google.android.material.slider.RangeSlider
    ...
    android:valueFrom="0.0"
    android:valueTo="100.0"
    app:values="@array/initial_slider_values"
    android:stepSize="10.0"  />
And in values/arrays.xml:
<resources>
  <array name="initial_slider_values">
    <item>20.0</item>
    <item>70.0</item>
  </array>
</resources>
Observe changes to a range slider:
rangeSlider.addOnSliderTouchListener(object : RangeSlider.OnSliderTouchListener {
    override fun onStartTrackingTouch(slider: RangeSlider) {
        // Responds to when slider's touch event is being started
    }
    override fun onStopTrackingTouch(slider: RangeSlider) {
        // Responds to when slider's touch event is being stopped
    }
})
rangeSlider.addOnChangeListener { rangeSlider, value, fromUser ->
    // Responds to when slider's value is changed
}
Making sliders accessible
Sliders support setting content descriptors for use with screen readers. While optional, we strongly encourage their use.
That can be done in XML via the android:contentDescription attribute or programmatically:
slider.contentDescription = contentDescription
If using a TextView to display the value of the slider, you should set android:labelFor so that screen readers announce that TextView refers to the slider.
The minimum touch target size of the thumb is 48dp by default. If a different size is needed, please set minTouchTargetSize in the style or the layout.
Adding/removing the value label
By default, the slider will show a value label above the thumb when it's selected. You can change how it's drawn via the app:labelBehavior attribute or setLabelBehavior method.
The modes of app:labelBehavior are:
- floating(default) - draws the label floating above the bounds of this view
- withinBounds- draws the label floating within the bounds of this view
- gone- prevents the label from being drawn
- visible- always draws the label
Setting a LabelFormatter
By using a LabelFormatter you can display the selected value using letters to indicate magnitude (e.g.: 1.5K, 3M, 12B). That can be achieved through the setLabelFormatter method.
The following example shows a slider for a price range in USD currency.
In code:
rangeSlider.setLabelFormatter { value: Float ->
    val format = NumberFormat.getCurrencyInstance()
    format.maximumFractionDigits = 0
    format.currency = Currency.getInstance("USD")
    format.format(value.toDouble())
}
Types
There are two types of sliders: 1. Continuous slider, 2. Discrete slider
A slider with two thumbs is called a range slider.
Continuous slider
Continuous sliders allow users to make meaningful selections that don’t require a specific value.
API and source code:
The following example shows a continuous slider.
In the layout:
<com.google.android.material.slider.Slider
    android:id="@+id/slider"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:contentDescription="@string/slider_desc"
    android:value="20.0"
    android:valueFrom="0.0"
    android:valueTo="100.0" />
Continuous range slider
API and source code:
- RangeSlider
The following example shows a continuous range slider.
In the layout:
<com.google.android.material.slider.RangeSlider
  android:id="@+id/range_slider"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:contentDescription="@string/slider_desc"
  app:values="@array/initial_slider_values"
  android:valueFrom="0.0"
  android:valueTo="100.0" />
Discrete slider
Discrete sliders display a numeric value label upon pressing the thumb, which allows a user to input an exact value.
API and source code:
The following example shows a discrete slider.
In the layout:
<com.google.android.material.slider.Slider
    ...
    android:stepSize="10.0" />
Discrete range slider
API and source code:
- RangeSlider
The following example shows a discrete range slider.
In the layout:
<com.google.android.material.slider.RangeSlider
    ...
    android:stepSize="10.0"  />
Anatomy and key properties
A slider has a track, one or two thumbs, and an optional value label. A discrete slider also has tick marks.
- Track
- Thumb
- Value label (optional)
- Tick mark (discrete sliders)
Track attributes
| Element | Attribute | Related method(s) | Default value | 
|---|---|---|---|
| Min value | android:valueFrom | setValueFrom | |
| getValueFrom | N/A | ||
| Max value | android:valueTo | setValueTo | |
| getValueTo | N/A | ||
| Step size (discrete) | android:stepSize | setStepSize | |
| getStepSize | N/A | ||
| Initial selected value (Slider) | android:value | setValue | |
| getValue | N/A | ||
| Initial selected values (RangeSlider) | app:values | setValues | |
| getValues | N/A | ||
| Height | app:trackHeight | setTrackHeight | |
| getTrackHeight | 4dp | ||
| Color | app:trackColor | setTrackTintList | |
| getTrackTintList | null | ||
| Color for track's active part | app:trackColorActive | setTrackActiveTintList | |
| getTrackActiveTintList | ?attr/colorPrimary | ||
| Color for track's inactive part | app:trackColorInactive | setTrackInactiveTintList | |
| getTrackInactiveTintList | ?attr/colorSurfaceVariant | ||
| Minimum separation for adjacent thumbs | app:minSeparation | setMinSeparation | |
| getMinSeparation | 0dp | 
Note: app:trackColor takes precedence over app:trackColorActive and app:trackColorInative. It's a shorthand for setting both values to the same thing.
Thumb attributes
| Element | Attribute | Related method(s) | Default value | 
|---|---|---|---|
| Color | app:thumbColor | setThumbTintList | |
| getThumbTintList | ?attr/colorPrimary | ||
| Radius | app:thumbRadius | setThumbRadiusResource | 
setThumbRadiusgetThumbRadius | 10dp | | Elevation | app:thumbElevation | setThumbElevationResourcesetThumbElevationgetThumbElevation | 2dp | | Halo color | app:haloColor | setHaloTintListgetHaloTintList | ?attr/colorPrimary at 24% | | Halo radius | app:haloRadius | setHaloRadiusResourcesetHaloRadiusgetHaloRadius | 24dp | | Stroke color | app:thumbStrokeColor | setThumbStrokeColorsetThumbStrokeColorResourcegetThumbStrokeColor | null | | Stroke width | app:thumbStrokeWidth | setThumbStrokeWidthsetThumbStrokeWidthResourcegetThumbStrokeWidth | 0dp |
Value label attributes
| Element | Attribute | Related method(s) | Default value | 
|---|---|---|---|
| Style | app:labelStyle | N/A | @style/Widget.Material3.Tooltip | 
| Formatter | N/A | setLabelFormatter | |
| hasLabelFormatter | null | ||
| Behavior | app:labelBehavior | setLabelBehavior | |
| getLabelBehavior | floating | 
Note: The value label is a Tooltip.
Tick mark attributes
| Element | Attribute | Related method(s) | Default value | 
|---|---|---|---|
| Color | app:tickColor | setTickTintList | |
| getTickTintList | null | ||
| Color for track's active part | app:tickColorActive | setTickActiveTintList | |
| getTickActiveTintList | ?attr/colorSurfaceVariant | ||
| Color for track's inactive part | app:tickColorInactive | setTickInactiveTintList | |
| getTickInactiveTintList | ?attr/colorPrimary | ||
| Tick visible | app:tickVisible | setTickVisible | |
| isTickVisible() | true | 
Note: app:tickColor takes precedence over app:tickColorActive and app:tickColorInative. It's a shorthand for setting both values to the same thing.
Styles
| Element | Style | 
|---|---|
| Default style | Widget.Material3.Slider | 
Default style theme attribute: ?attr/sliderStyle
See the full list of styles and attributes.
Theming sliders
Sliders support Material Theming which can customize color and typography.
Slider theming example
API and source code:
- Slider
- RangeSlider
The following example shows a range slider with Material Theming.
Implementing slider theming
Use theme attributes and styles in res/values/styles.xml which applies to all sliders and affects other components:
<style name="Theme.App" parent="Theme.Material3.*">
    ...
    <item name="colorPrimary">@color/shrine_pink_100</item>
    <item name="colorOnPrimary">@color/shrine_pink_900</item>
    <item name="colorOnSurface">@color/shrine_pink_100</item>
</style>
Use a default style theme attribute, styles and a theme overlay which applies to all sliders but does not affect other components:
<style name="Theme.App" parent="Theme.Material3.*">
    ...
    <item name="sliderStyle">@style/Widget.App.Slider</item>
</style>
<style name="Widget.App.Slider" parent="Widget.Material3.Slider">
    <item name="materialThemeOverlay">@style/ThemeOverlay.App.Slider</item>
    <item name="labelStyle">@style/Widget.App.Tooltip</item>
  </style>
<style name="ThemeOverlay.App.Slider" parent="">
    <item name="colorPrimary">@color/shrine_pink_100</item>
    <item name="colorOnPrimary">@color/shrine_pink_900</item>
    <item name="colorOnSurface">@color/shrine_pink_100</item>
</style>
<style name="Widget.App.Tooltip" parent="Widget.Material3.Tooltip">
    <item name="android:textAppearance">@style/TextAppearance.App.Tooltip</item>
    <item name="backgroundTint">@color/shrine_pink_900</item>
  </style>
<style name="TextAppearance.App.Tooltip" parent="TextAppearance.Material3.BodySmall">
  <item name="android:textColor">@color/shrine_pink_100</item>
  <item name="fontFamily">@font/rubik</item>
  <item name="android:fontFamily">@font/rubik</item>
</style>
Use the style in the layout, which affects only this specific slider:
<com.google.android.material.slider.RangeSlider
    ...
    style="@style/Widget.App.Slider"  /> 
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