<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">  <ImageView        android:id="@+id/image"        android:layout_width="match_parent"        android:layout_height="240dp"        android:src="@drawable/lijiang" />    <RatingBar        android:id="@+id/ratingBar"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="center"        android:numStars="5"        android:progress="255"        android:stepSize="0.5" /></LinearLayout>

package com.example.ratingbar;import android.app.Activity;import android.os.Bundle;import android.widget.ImageView;import android.widget.RatingBar;import android.widget.RatingBar.OnRatingBarChangeListener;public class MainActivity extends Activity {    ImageView image;    RatingBar ratingBar;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        image=(ImageView) findViewById(R.id.image);        ratingBar=(RatingBar) findViewById(R.id.ratingBar);        ratingBar.setOnRatingBarChangeListener(new OnRatingBarChangeListener(){            @Override            public void onRatingChanged(RatingBar ratingBar, float rating,                    boolean fromUser) {                image.setImageAlpha((int) (rating*255/5));                            }                    });    }}