tabhost通过手势滑动切换activity

1. package com.mars.mp3player;  
2.   
3. import android.app.TabActivity;  
4. import android.content.Intent;  
5. import android.os.Bundle;  
6. import android.util.Log;  
7. import android.view.GestureDetector;  
8. import android.view.GestureDetector.SimpleOnGestureListener;  
9. import android.view.Menu;  
10. import android.view.MotionEvent;  
11. import android.view.View;  
12. import android.widget.TabHost;  
13. import android.widget.TabHost.TabSpec;  
14.   
15. public class ActivityMain extends TabActivity {  
16.     private TabSpec tabSpec;  
17.     private TabHost tabHost;  
18.     private Intent intent;  
19.     // *********************************  
20.     private static final int SWIPE_MIN_DISTANCE = 120;  
21.     private static final int SWIPE_MAX_OFF_PATH = 250;  
22.     private static final int SWIPE_THRESHOLD_VELOCITY = 200;  
23.     private GestureDetector gestureDetector;  
24.     View.OnTouchListener gestureListener;  
25.   
26.     int currentView = 0;  
27.     private static int maxTabIndex = 2;  
28.   
29.     @Override  
30.     public void onCreate(Bundle savedInstanceState) {  
31.         super.onCreate(savedInstanceState);  
32.         super.setContentView(R.layout.activity_main);  
33.         UtilVar.activities.add(ActivityMain.this);  
34.         this.initTableHost();  
35.   
36.         gestureDetector = new GestureDetector(new MyGestureDetector());  
37.         gestureListener = new View.OnTouchListener() {  
38.             public boolean onTouch(View v, MotionEvent event) {  
39.                 if (gestureDetector.onTouchEvent(event)) {  
40.                     return true;  
41.                 }  
42.                 return false;  
43.             }  
44.         };  
45.   
46.     }  
47.   
48.     /** 
49.      * tablehost的初始化，代码完成 
50.      */  
51.     private void initTableHost() {  
52.         tabHost = super.getTabHost();  
53.         // 歌曲列表  
54.         intent = new Intent(ActivityMain.this, ActivityList.class);  
55.         tabSpec = tabHost  
56.                 .newTabSpec("歌曲列表")  
57.                 .setIndicator("歌曲列表",  
58.                         getResources().getDrawable(R.drawable.ic_launcher))  
59.                 .setContent(intent);  
60.         tabHost.addTab(tabSpec);  
61.         // 正在播放  
62.         intent = new Intent(ActivityMain.this, ActivityPlaying.class);  
63.         tabSpec = tabHost  
64.                 .newTabSpec("正在播放")  
65.                 .setIndicator("正在播放",  
66.                         getResources().getDrawable(R.drawable.ic_launcher))  
67.                 .setContent(intent);  
68.         tabHost.addTab(tabSpec);  
69.         // 专辑列表  
70.         intent = new Intent(ActivityMain.this, ActivityLyric.class);  
71.         tabSpec = tabHost  
72.                 .newTabSpec("歌词显示")  
73.                 .setIndicator("歌词显示",  
74.                         getResources().getDrawable(R.drawable.ic_launcher))  
75.                 .setContent(intent);  
76.         tabHost.addTab(tabSpec);  
77.         // 设置当前tab  
78.         tabHost.setCurrentTab(1);  
79.     }  
80.   
81.     // 左右滑动刚好页面也有滑动效果  
82.     class MyGestureDetector extends SimpleOnGestureListener {  
83.         @Override  
84.         public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,  
85.                 float velocityY) {  
86.             TabHost tabHost = getTabHost();  
87.             System.out.println("************");  
88.             try {  
89.                 if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH)  
90.                     return false;  
91.                 // right to left swipe  
92.                 if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE  
93.                         && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {  
94.                     Log.i("test", "right");  
95.                     if (currentView == maxTabIndex) {  
96.                         currentView = 0;  
97.                     } else {  
98.                         currentView++;  
99.                     }  
100.                     tabHost.setCurrentTab(currentView);  
101.                 } else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE  
102.                         && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {  
103.                     Log.i("test", "left");  
104.                     if (currentView == 0) {  
105.                         currentView = maxTabIndex;  
106.                     } else {  
107.                         currentView--;  
108.                     }  
109.                     tabHost.setCurrentTab(currentView);  
110.                 }  
111.             } catch (Exception e) {  
112.             }  
113.             return false;  
114.         }  
115.     }  
116.   
117.     @Override  
118.     public boolean dispatchTouchEvent(MotionEvent event) {  
119.         if (gestureDetector.onTouchEvent(event)) {  
120.             event.setAction(MotionEvent.ACTION_CANCEL);  
121.         }  
122.         return super.dispatchTouchEvent(event);  
123.     }  
124.   
125.     @Override  
126.     public boolean onCreateOptionsMenu(Menu menu) {  
127.         getMenuInflater().inflate(R.menu.activity_main, menu);  
128.         return true;  
129.     }  
130.   
131. }  
132. // 主要代码就这样吧，以后就不必到处找手势跳转activity的例子了。