tabhost通过手势滑动切换activity

public class Main extends TabActivity {
private static final int SWIPE_MIN_DISTANCE = 120;
private static final int SWIPE_MAX_OFF_PATH = 250;
private static final int SWIPE_THRESHOLD_VELOCITY = 200;
private GestureDetector gestureDetector;
View.OnTouchListener gestureListener;
private Animation slideLeftIn;
private Animation slideLeftOut;
private Animation slideRightIn;
private Animation slideRightOut;
private ViewFlipper viewFlipper;

int currentView = 0;
private static int maxTabIndex = 2;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
TabHost tabHost = getTabHost();
tabHost.addTab(tabHost.newTabSpec("tab1").setIndicator("tab1 ")
.setContent(new Intent(this, Activity1.class)));

tabHost.addTab(tabHost.newTabSpec("tab2").setIndicator("tab2 ")
.setContent(new Intent(this, Activity2.class)));

tabHost.addTab(tabHost.newTabSpec("tab3").setIndicator("tab3 ")
.setContent(new Intent(this, Activity3.class)));
tabHost.setCurrentTab(0);
slideLeftIn = AnimationUtils.loadAnimation(this, R.anim.slide_left_in);
slideLeftOut = AnimationUtils
.loadAnimation(this, R.anim.slide_left_out);
slideRightIn = AnimationUtils
.loadAnimation(this, R.anim.slide_right_in);
slideRightOut = AnimationUtils.loadAnimation(this,
R.anim.slide_right_out);

gestureDetector = new GestureDetector(new MyGestureDetector());
gestureListener = new View.OnTouchListener() {
public boolean onTouch(View v, MotionEvent event) {
if (gestureDetector.onTouchEvent(event)) {
return true;
}
return false;
}
};
}

class MyGestureDetector extends SimpleOnGestureListener {
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
TabHost tabHost = getTabHost();
try {
if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH)
return false;
// right to left swipe
if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE
&& Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Log.i("test ", "right");
if (currentView == maxTabIndex) {
currentView = 0;
} else {
currentView++;
}
tabHost.setCurrentTab(currentView);
} else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE
&& Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Log.i("test ", "left");
if (currentView == 0) {
currentView = maxTabIndex;
} else {
currentView--;
}
tabHost.setCurrentTab(currentView);
}
} catch (Exception e) {
// nothing
}
return false;
}
}

// @Override
// public boolean onTouchEvent(MotionEvent event) {
// if (gestureDetector.onTouchEvent(event))
// return true;
// else
// return false;
// }

@Override
public boolean dispatchTouchEvent(MotionEvent event) {

if(gestureDetector.onTouchEvent(event)){
event.setAction(MotionEvent.ACTION_CANCEL);
}

return super.dispatchTouchEvent(event);

}
}



xml文件如下：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout  xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
<ImageButton
android:id="@+id/button1"
android:layout_weight="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</ImageButton>
<ImageButton
android:id="@+id/button2"
android:layout_weight="1"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</ImageButton>
</LinearLayout>
<TabHost
android:id="@android:id/tabhost" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout android:orientation="vertical"
android:layout_width="fill_parent" android:layout_height="fill_parent">
<TabWidget android:id="@android:id/tabs"
android:layout_width="fill_parent" android:layout_height="wrap_content" />
<FrameLayout android:id="@android:id/tabcontent"
android:layout_width="fill_parent" android:layout_height="fill_parent" />
</LinearLayout>
</TabHost>
</LinearLayout>