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Android手势识别和控制 GestureDetecor

为 了加强鼠标响应事件,Android提供了GestureDetector手势识别类。通过 GestureDetector.OnGestureListener来获取当前被触发的操作手势(Single Tap Up、Show Press、Long Press、Scroll、Down、Fling),......

为 了加强鼠标响应事件,Android提供了GestureDetector手势识别类。通过 GestureDetector.OnGestureListener来获取当前被触发的操作手势(Single Tap Up、Show Press、Long Press、Scroll、Down、Fling),具体包括以下几种:

       boolean onDoubleTap(MotionEvent e)
              解释:双击的第二下Touch down时触发
       boolean onDoubleTapEvent(MotionEvent e)
              解释:双击的第二下Touch down和up都会触发,可用e.getAction()区分。
       boolean onDown(MotionEvent e)
              解释:Touch down时触发
       boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
              解释:Touch了滑动一点距离后,up时触发。
       void onLongPress(MotionEvent e)
              解释:Touch了不移动一直Touch down时触发
       boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)
              解释:Touch了滑动时触发。
       void onShowPress(MotionEvent e)
              解释:Touch了还没有滑动时触发 (与onDown,onLongPress比较,onDown只要Touch down一定立刻触发。
              而Touchdown后过一会没有滑动先触发onShowPress再是onLongPress。
              所以Touchdown后一直不滑动,onDown->onShowPress->onLongPress这个顺序触发。
       boolean onSingleTapConfirmed(MotionEvent e)
       boolean onSingleTapUp(MotionEvent e)
              解释:上面这两个函数都是在touch down后又没有滑动(onScroll),又没有长按(onLongPress),然后Touchup时触发。
              点击一下非常快的(不滑动)Touchup:
              onDown->onSingleTapUp->onSingleTapConfirmed
              点击一下稍微慢点的(不滑动)Touchup:
              onDown->onShowPress->onSingleTapUp->onSingleTapConfirmed
              使用GestureDetector需要在View中重写onTouchEvent事件,例如:

 

 

GestureDetector mGesture = null;  
@Override  
    public boolean onTouch(View v, MotionEvent event)  
    {  
        // TODO Auto-generated method stub  
        return mGesture.onTouchEvent(event);  
    }  

 

 

package com.jiubang.android.gesturetest;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.View.OnTouchListener;
import android.widget.Button;

public class GestureActivity extends Activity
			implements OnTouchListener
{
	private Button mButton = null;
	GestureDetector mGesture = null;
	
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        Log.i("TEST", "onCreate");
        mButton = (Button)findViewById(R.id.button1);
        mButton.setOnTouchListener(this);
        mGesture = new GestureDetector(this, new GestureListener());
    }

	@Override
	public boolean onTouch(View v, MotionEvent event)
	{
		// TODO Auto-generated method stub
		return mGesture.onTouchEvent(event);
	}
	
	class GestureListener extends SimpleOnGestureListener
	{

		@Override
		public boolean onDoubleTap(MotionEvent e)
		{
			// TODO Auto-generated method stub
			Log.i("TEST", "onDoubleTap");
			return super.onDoubleTap(e);
		}

		@Override
		public boolean onDown(MotionEvent e)
		{
			// TODO Auto-generated method stub
			Log.i("TEST", "onDown");
			return super.onDown(e);
		}

		@Override
		public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
				float velocityY)
		{
			// TODO Auto-generated method stub
			Log.i("TEST", "onFling:velocityX = " + velocityX + " velocityY" + velocityY);
			return super.onFling(e1, e2, velocityX, velocityY);
		}

		@Override
		public void onLongPress(MotionEvent e)
		{
			// TODO Auto-generated method stub
			Log.i("TEST", "onLongPress");
			super.onLongPress(e);
		}

		@Override
		public boolean onScroll(MotionEvent e1, MotionEvent e2,
				float distanceX, float distanceY)
		{
			// TODO Auto-generated method stub
			Log.i("TEST", "onScroll:distanceX = " + distanceX + " distanceY = " + distanceY);
			return super.onScroll(e1, e2, distanceX, distanceY);
		}

		@Override
		public boolean onSingleTapUp(MotionEvent e)
		{
			// TODO Auto-generated method stub
			Log.i("TEST", "onSingleTapUp");
			return super.onSingleTapUp(e);
		}
		
	}
}