布局文件内容：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="match_parent"
        android:layout_height="400dp"
        android:src="@drawable/dog_004"
        android:scaleType="fitCenter"
        />

    <RatingBar
        android:id="@+id/ratingBar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:numStars="5"
        android:max="255"
        android:progress="255"
        android:stepSize="0.5"
        />

</LinearLayout>

主程序文件内容;

package com.toby.personal.testlistview;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.ImageView;
import android.widget.RatingBar;

public class MainActivity extends AppCompatActivity {

    final private static String TAG = "Toby_Test";


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final ImageView imageView = (ImageView) findViewById(R.id.imageView);
        final RatingBar ratingBar = (RatingBar) findViewById(R.id.ratingBar);
        ratingBar.setOnRatingBarChangeListener(new RatingBar.OnRatingBarChangeListener() {

            @Override
            public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) {
                imageView.setImageAlpha((int)(rating * 255 /5));
            }
        });
    }

}

运行效果：

RatingBar 使用示例

参考文献：《疯狂Android讲义（第2版）》