Android SurfaceView 透明和半透明

[plain]  view plain copy print ?

1. <span style="font-size:18px;color:#ff0000;">透明//Transparent  
2. 半透明//Translucent</span>  

[java]  view plain copy print ?

1. package rw.Trans;  
2.   
3. import android.app.Activity;  
4. import android.content.Context;  
5. import android.graphics.Bitmap;  
6. import android.graphics.BitmapFactory;  
7. import android.graphics.Canvas;  
8. import android.graphics.PixelFormat;  
9. import android.os.Bundle;  
10. import android.view.MotionEvent;  
11. import android.view.SurfaceHolder;  
12. import android.view.SurfaceHolder.Callback;  
13. import android.view.SurfaceView;  
14.   
15. public class TransParentActivity extends Activity {  
16.     /** Called when the activity is first created. */  
17.     class MySurfaceView extends SurfaceView implements Callback{  
18.         float left,top;  
19.         Bitmap bitmap=BitmapFactory.decodeResource(getResources(), R.drawable.reen);  
20.         public MySurfaceView(Context context) {  
21.             super(context);  
22.             // TODO Auto-generated constructor stub  
23.             <span style="color:#ff0000;">getHolder().setFormat(PixelFormat.TRANSPARENT);//设置为透明  
24.             //getHolder().setFormat(PixelFormat.TRANSLUCENT);//半透明</span>  
25.             getHolder().addCallback(this);  
26.             setFocusable(true);  
27.         }  
28.   
29.         @Override  
30.         public void surfaceChanged(SurfaceHolder holder, int format, int width,  
31.                 int height) {  
32.             // TODO Auto-generated method stub  
33.               
34.         }  
35.   
36.         @Override  
37.         public void surfaceCreated(SurfaceHolder holder) {  
38.             // TODO Auto-generated method stub  
39.          doDraw();    
40.         }  
41.   
42.         private void doDraw() {  
43.             // TODO Auto-generated method stub  
44.             Canvas canvas=getHolder().lockCanvas();  
45.             canvas.drawBitmap(bitmap, left, top, null);  
46.             getHolder().unlockCanvasAndPost(canvas);  
47.         }  
48.   
49.         @Override  
50.         public void surfaceDestroyed(SurfaceHolder holder) {  
51.             // TODO Auto-generated method stub  
52.               
53.         }  
54.           
55.         /* (non-Javadoc) 
56.          * @see android.app.Activity#onTouchEvent(android.view.MotionEvent) 
57.          */  
58.         @Override  
59.         public boolean onTouchEvent(MotionEvent event) {  
60.             // TODO Auto-generated method stub  
61.             left=event.getX();  
62.             top=event.getY();  
63.             doDraw();  
64.               
65.             return super.onTouchEvent(event);  
66.         }  
67.     }  
68.     @Override  
69.     public void onCreate(Bundle savedInstanceState) {  
70.         super.onCreate(savedInstanceState);  
71.         setContentView(new MySurfaceView(getApplicationContext()));  
72.           
73.     }  
74.       
75. }  

AndroidManifest.xml

[html]  view plain copy print ?

1. <p><?xml version="1.0" encoding="utf-8"?>  
2. <manifest xmlns:android="<a href="http://schemas.android.com/apk/res/android">http://schemas.android.com/apk/res/android</a>"  
3.       package="rw.Trans"  
4.       android:versionCode="1"  
5.       android:versionName="1.0">  
6.     <uses-sdk android:minSdkVersion="10" /></p><p>    <application android:icon="@drawable/icon" android:label="@string/app_name">  
7.         <activity android:name=".TransParentActivity"  
8.                   android:label="Transparent SurfaceView"  
9.                  <span style="color:#ff0000;"> android:theme="@android:style/Theme.Translucent"  
10. </span>                  ></p><p>                    
11.             <intent-filter>  
12.                 <action android:name="android.intent.action.MAIN" />  
13.                 <category android:name="android.intent.category.LAUNCHER" />  
14.             </intent-filter>  
15.         </activity></p><p>    </application>  
16. </manifest></p>