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Slider

Sliders allow users to make selections from a range of values.

"Slider with sound icon buttons on each end."

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

Single point sliders

A Slider can be added in a layout like so:

<!-- 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"  />

Changes to a slider can be observed like so:

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
}

Range slider

Similarly, a RangeSlider can be added in a layout like so:

<!-- Continuous slider -->
<com.google.android.material.slider.RangeSlider
    ...
    android:valueFrom="0.0"
    android:valueTo="100.0"
    app:values="@array/initial_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>

Changes to a range slider can be observed like so:

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 like so:

slider.contentDescription = contentDescription

Additionaly, if using a TextView to display the value of the slider, you should set android:labelFor on it, so that screen readers announce that TextView refers to the slider.

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

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 prince range in the USD currency.

"Range slider with range of $0 to $100. Left thumb is set at $20, right thumb at $70."

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

"Slider examples of both continuous and discrete sliders."

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.

"Continuous sliders with pressed thumb valued at 20."

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:

The following example shows a continuous range slider.

"Continuous range slider with left thumb at 20 and right thumb at 70."

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.

"Discrete single point slider with pressed thumb at a value of 20."

In the layout:

<com.google.android.material.slider.Slider
    ...
    android:stepSize="5.0" />

Discrete range slider

API and source code:

The following example shows a discrete range slider.

"Discrete range slider with left thumb at 20 and right thumb at 70."

In the layout:

<com.google.android.material.slider.RangeSlider
    ...
    android:stepSize="5.0"  />

Anatomy and key properties

A slider has a track, one or two thumbs, and optional value label. A discrete slider also has tick marks.

Slider anatomy diagram

  1. Track
  2. Thumb
  3. Value label (optional)
  4. Tick mark (discrete sliders)

Track attributes

  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/colorPrimary at 24%
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

  Attribute Related method(s) Default value
Color app:thumbColor setThumbTintList
getThumbTintList		 ?attr/colorPrimary
Radius app:thumbRadius setThumbRadiusResource
setThumbRadius
getThumbRadius		 10dp
Elevation app:thumbElevation setThumbElevationResource
setThumbElevation
getThumbElevation		 1dp
Halo color app:haloColor setHaloTintList
getHaloTintList		 ?attr/colorPrimary at 24%
Halo radius app:haloRadius setHaloRadiusResource
setHaloRadius
getHaloRadius		 24dp

Value label attributes

  Attribute Related method(s) Default value
Style app:labelStyle N/A @style/Widget.MaterialComponents.Tooltip
Formatter N/A setLabelFormatter
hasLabelFormatter		 null
Behavior app:labelBehavior setLabelBehavior
getLabelBehavior		 floating

Note: The value label is a Tooltip.

Tick mark attributes

  Attribute Related method(s) Default value
Color app:tickColor setTickTintList
getTickTintList		 null
Color for track's active part app:tickColorActive setTickActiveTintList
getTickActiveTintList		 ?attr/colorOnPrimary at 54%
Color for track's inactive part app:tickColorInactive setTickInactiveTintList
getTickInactiveTintList		 ?attr/colorPrimary at 54%

Note: app:tickColor takes precedence over app:tickColorActive and app:tickColorInative. It's a shorthand for setting both values to the same thing.

Styles

  Style
Default style Widget.MaterialComponents.Slider

Default style theme attribute: ?attr/sliderStyle

See the full list of styles and attributes.

Theming sliders

Sliders support Material Theming and can be customized in terms of color and typography.

Slider theming example

API and source code:

The following example shows a range slider with Material Theming.

"Slider theming example with pink and brown colors."

Implementing slider theming

Using theme attributes and styles in res/values/styles.xml (themes all sliders and affects other components):

<style name="Theme.App" parent="Theme.MaterialComponents.*">
    ...
    <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>

or using a default style theme attribute, styles and a theme overlay (themes all sliders but does not affect other components):

<style name="Theme.App" parent="Theme.MaterialComponents.*">
    ...
    <item name="sliderStyle">@style/Widget.App.Slider</item>
</style>

<style name="Widget.App.Slider" parent="Widget.MaterialComponents.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.MaterialComponents.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.MaterialComponents.Tooltip">
  <item name="android:textColor">@color/shrine_pink_100</item>
  <item name="fontFamily">@font/rubik</item>
  <item name="android:fontFamily">@font/rubik</item>
</style>

or using the style in the layout (affects only this specific slider):

<com.google.android.material.slider.RangeSlider
    ...
    style="@style/Widget.App.Slider"  />