拖动条SeekBar及星级评分条

1.布局

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

 2     xmlns:tools="http://schemas.android.com/tools"

 3     android:layout_width="match_parent"

 4     android:layout_height="match_parent"

 5     android:orientation="vertical"

 6     tools:context=".AndroidSeekBarActivity" >

 7 

 8     <ImageView

 9         android:id="@+id/img"

10         android:layout_width="match_parent"

11         android:layout_height="240px"

12         android:src="@drawable/mm" />

13 

14     <SeekBar

15         android:id="@+id/sekbar"

16         android:layout_width="match_parent"

17         android:layout_height="wrap_content"

18         android:max="255"

19         android:progress="255"

20         android:thumb="@drawable/sj" />

21 

22     <RatingBar

23         android:id="@+id/ratbar"

24         android:layout_width="match_parent"

25         android:layout_height="wrap_content"

26         android:max="255"

27         android:numStars="5"

28         android:progress="255"

29         android:stepSize="0.5" />

30 

31 </LinearLayout>

2.逻辑控制

 1 package com.example.androidseekbar;

 2 

 3 import android.os.Bundle;

 4 import android.app.Activity;

 5 import android.view.Menu;

 6 import android.widget.ImageView;

 7 import android.widget.RatingBar;

 8 import android.widget.RatingBar.OnRatingBarChangeListener;

 9 import android.widget.SeekBar;

10 import android.widget.SeekBar.OnSeekBarChangeListener;

11 

12 public class AndroidSeekBarActivity extends Activity {

13 

14     @Override

15     protected void onCreate(Bundle savedInstanceState) {

16         super.onCreate(savedInstanceState);

17         setContentView(R.layout.activity_android_seek_bar);

18 

19         final ImageView img = (ImageView) this.findViewById(R.id.img);

20         SeekBar sekbar = (SeekBar) this.findViewById(R.id.sekbar);

21         sekbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

22 

23             @Override

24             public void onStopTrackingTouch(SeekBar seekBar) {

25                 // TODO Auto-generated method stub

26 

27             }

28 

29             @Override

30             public void onStartTrackingTouch(SeekBar seekBar) {

31                 // TODO Auto-generated method stub

32 

33             }

34 

35             @Override

36             public void onProgressChanged(SeekBar seekBar, int progress,

37                     boolean fromUser) {

38                 // 拖动时触发

39                 img.setAlpha(progress);

40             }

41         });

42         

43         RatingBar ratbar=(RatingBar)this.findViewById(R.id.ratbar);

44         ratbar.setOnRatingBarChangeListener(new OnRatingBarChangeListener() {

45             

46             @Override

47             public void onRatingChanged(RatingBar arg0, float rating, boolean arg2) {

48                 //动态改变图片透明度

49                 img.setAlpha((int)(rating*255/5));

50             }

51         });

52     }

53 

54     @Override

55     public boolean onCreateOptionsMenu(Menu menu) {

56         // Inflate the menu; this adds items to the action bar if it is present.

57         getMenuInflater().inflate(R.menu.activity_android_seek_bar, menu);

58         return true;

59     }

60 

61 }