How to use fastScrollEnabled in RecyclerView?

As you know that, RecyclerView supports “fast scroller” in Support Library 26.0.0.

Note: Keep in mind it’s XML-only though.

Add the attributes to the RecyclerView tag in your layout file:

<android.support.v7.widget.RecyclerView
    xmlns:app="http://schemas.android.com/apk/res-auto"
    ...
    app:fastScrollEnabled="true"
    app:fastScrollHorizontalThumbDrawable="@drawable/fast_scroll_thumb"
    app:fastScrollHorizontalTrackDrawable="@drawable/fast_scroll_track"
    app:fastScrollVerticalThumbDrawable="@drawable/fast_scroll_thumb"
    app:fastScrollVerticalTrackDrawable="@drawable/fast_scroll_track"
/>

Make two drawables. The "track" drawable can be any drawable, but the "thumb" drawable must be a state list drawable.

Example drawable/fast_scroll_track.xml file:

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#80ffffff" />
</shape>

Example drawable/fast_scroll_thumb.xml file:

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true">
        <shape android:shape="rectangle">
            <solid android:color="#ff0" />
        </shape>
    </item>
    <item>
        <shape android:shape="rectangle">
            <solid android:color="#fff" />
        </shape>
    </item>
</selector>

With Support Library 26, we can easily enable fast scrolling for RecyclerView. Let’s get to it!

Let’s go over each property one by one :

1. fastScrollEnabled : boolean value to enable the fast scrolling. Setting this as true will require that we provide the following four properties.
2. fastScrollHorizontalThumbDrawable : A StateListDrawable that will be used to draw the thumb which will be draggable across the horizontal axis.
3. fastScrollHorizontalTrackDrawable : A StateListDrawable that will be used to draw the line that will represent the scrollbar on horizontal axis.
4. fastScrollVerticalThumbDrawable : A StateListDrawable that will be used to draw the thumb which will be draggable on vertical axis.
5. fastScrollVerticalTrackDrawable : A StateListDrawable that will be used to draw the line that will represent the scrollbar on vertical axis.

add in build.gradle

    dependencies {
    ....
    compile 'com.android.support:design:26.0.1'
    compile 'com.android.support:recyclerview-v7:26.0.1'
    ....
}

Since Support Library 26 has now been moved to Google’s maven repository, let’s include that in our project level build.gradle

allprojects {
    repositories {
        jcenter()
        maven {
            url "https://maven.google.com"
        }
    }
}

activity_main.xml

<android.support.v7.widget.RecyclerView
    android:id="@+id/recyclerView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:fastScrollEnabled="true"
    app:fastScrollHorizontalThumbDrawable="@drawable/thumb_drawable"
    app:fastScrollHorizontalTrackDrawable="@drawable/line_drawable"
    app:fastScrollVerticalThumbDrawable="@drawable/thumb_drawable"
    app:fastScrollVerticalTrackDrawable="@drawable/line_drawable">

 </android.support.v7.widget.RecyclerView>

add below four xml file in your drawable folder,

line_drawable.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:state_pressed="true"
        android:drawable="@drawable/line"/>

    <item
        android:drawable="@drawable/line"/>
</selector>

line.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle">

    <solid android:color="@android:color/darker_gray" />

    <padding
        android:top="10dp"
        android:left="10dp"
        android:right="10dp"
        android:bottom="10dp"/>
</shape>

thumb_drawable.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:state_pressed="true"
        android:drawable="@drawable/thumb"/>

    <item
        android:drawable="@drawable/thumb"/>
</selector>

thumb.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle">

    <corners
        android:topLeftRadius="44dp"
        android:topRightRadius="44dp"
        android:bottomLeftRadius="44dp" />

    <padding
        android:paddingLeft="22dp"
        android:paddingRight="22dp" />

    <solid android:color="@color/colorPrimaryDark" />

</shape>