Rating Bar

From google documentation.

A RatingBar is an extension of SeekBar and ProgressBar that shows a rating in stars. The user can touch/drag or use arrow keys to set the rating when using the default size RatingBar. The smaller RatingBar style (ratingBarStyleSmall) and the larger indicator-only style (ratingBarStyleIndicator) do not support user interaction and should only be used as indicators.

How to add?

I. In your build.gradle add latest appcompat library.

dependencies {  
    compile 'com.android.support:appcompat-v7:X.X.X' // where X.X.X version
}

II. Make your activity extend android.support.v7.app.AppCompatActivity.

public class MainActivity extends AppCompatActivity {  
    ...
}

III. Declare your RatingBar inside any layout.xml file.

<RatingBar  
    android:rating="3.5"
    android:stepSize="0.5"
    android:numStars="5"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"/>

How to style?

I. Declare custom style in your styles.xml file.

<style name="RatingBar" parent="Theme.AppCompat">  
    <item name="colorControlNormal">@color/indigo</item>
    <item name="colorControlActivated">@color/pink</item>
</style>  

II. Apply this style to your RatingBar via android:theme attribute.

<RatingBar  
    android:theme="@style/RatingBar"
    android:rating="3"
    android:stepSize="0.5"
    android:numStars="5"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"/>