Android 用手势切换activity

<span style="font-size: 24px;"><strong></strong></span><pre name="code" class="java">package rw.gest;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.GestureDetector.OnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.LinearLayout;
import android.widget.Toast;
public class Gest01Activity extends Activity{
    
    GestureDetector detector;
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        detector=new GestureDetector(new GestureListener());
        LinearLayout layout=(LinearLayout)findViewById(R.id.linearlayout);
        layout.setOnTouchListener(new TouhListener());
        layout.setLongClickable(true);
        
    }
//触摸屏幕监听
	class TouhListener implements OnTouchListener{

		@Override
		public boolean onTouch(View v, MotionEvent event) {
			// TODO Auto-generated method stub
			Toast.makeText(getApplicationContext(), "----?", event.getAction()).show();
			return detector.onTouchEvent(event);
		}
		
	}
	//手势滑动监听
	class GestureListener implements OnGestureListener{

		@Override
		public boolean onDown(MotionEvent e) {
			// TODO Auto-generated method stub
		/*
		 * 当触摸屏幕是使用这个函数
		 */
			Toast.makeText(getApplicationContext(), "-----------> onDown", Toast.LENGTH_LONG).show();
			return false;
		}

		@Override
		public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
				float velocityY) {
			// e1 触摸的起始位置，e2 触摸的结束位置，velocityX X轴每一秒移动的像素速度（大概这个意思） velocityY 就是Ｙ咯
			//手势左,上为正 ——，右，下为负正
			if (e2.getX()-e1.getX()>50) {
				//为什么是50？ 这个根据你的模拟器大小来定，看看模拟器宽度，e2.getX()-e1.getX()<屏幕宽度就ＯＫ
				Toast.makeText(getApplicationContext(), "向右滑动", Toast.LENGTH_LONG).show();
				//要触发什么事件都在这里写就OK 
				//如果要跳转到另外一个activity
				Intent intent=new Intent(Gest01Activity.this, toActivity.class);
				startActivity(intent);
			}
			if (Math.abs(e2.getX()-e1.getX())>50) {
				Toast.makeText(getApplicationContext(), "向左滑动", Toast.LENGTH_LONG).show();
			}
			if (Math.abs(e2.getY()-e1.getY())>50) {
				Toast.makeText(getApplicationContext(), "向上滑动", Toast.LENGTH_LONG).show();
			}
			if (e2.getY()-e1.getY()>50) {
				Toast.makeText(getApplicationContext(), "向下滑动", Toast.LENGTH_LONG).show();
			}
			return false;
		}

		@Override
		public void onLongPress(MotionEvent e) {
			// TODO Auto-generated method stub\
		  /*
		   * 长按事件  一切长事件按屏幕想要触发的事件都在这里写
		   */
			Toast.makeText(getApplicationContext(), "------------> onLongPress", Toast.LENGTH_LONG).show();
		}

		@Override
		public boolean onScroll(MotionEvent e1, MotionEvent e2,
				float distanceX, float distanceY) {
			// TODO Auto-generated method stub
			/*
			 * 这个函数大概是这样，英语差了，有误差。distanceX 是X轴路径长度，distanceY 是Y轴路径长度（注意：是路径，不是位移）;
			 */
			Toast.makeText(getApplicationContext(), "------------> onScroll", Toast.LENGTH_LONG).show();
			return false;
		}

		@Override
		public void onShowPress(MotionEvent e) {
			// TODO Auto-generated method stub
			/*
			 * 
			 */
			Toast.makeText(getApplicationContext(), "------------> onShowPress", Toast.LENGTH_LONG).show();
		}

		@Override
		public boolean onSingleTapUp(MotionEvent e) {
			// TODO Auto-generated method stub
			Toast.makeText(getApplicationContext(), "------------> onSingleTapUp", Toast.LENGTH_LONG).show();
			return false;
		}
		
	}
}</pre>

<?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"
     android:id="@+id/linearlayout"
    >

<ImageView android:src="@drawable/eight" android:id="@+id/imageView1" android:layout_height="match_parent" android:layout_width="match_parent"></ImageView>
</LinearLayout>

先上代码再看图，解释在代码中.............