Android欢迎界面图片切换

【实例截图】

【核心代码】

package com.yourannet.android.welcome;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.GestureDetector.OnGestureListener;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.AnimationUtils;
import android.widget.Toast;
import android.widget.ViewFlipper;

public class Welcome extends Activity implements OnGestureListener {
    //实现拖动类效果属性声明
	private ViewFlipper flipper;
	private GestureDetector detector;
	
	/** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //注册一个用于手势识别的类
        detector = new GestureDetector(this);
        flipper = (ViewFlipper)this.findViewById(R.id.Viewflipper);
        
        flipper.addView(addView(R.layout.welc_1));
        flipper.addView(addView(R.layout.welc_2));
        flipper.addView(addView(R.layout.welc_3));
    }
    
    //添加视图
    private View addView(int layout){
    	LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    	View view = inflater.inflate(layout, null);
    	return view;
    }
	@Override
	public boolean onTouchEvent(MotionEvent event) {
		// TODO Auto-generated method stub
		return this.detector.onTouchEvent(event);
	}

	//用户轻触触摸屏，由1个MotionEvent ACTION_DOWN触发
	public boolean onDown(MotionEvent arg0) {
		// TODO Auto-generated method stub
		Toast.makeText(this, "onDown",Toast.LENGTH_SHORT).show();
		return false;
	}

	//用户按下触摸屏，快速移动后松开，由1个MotionEvent ACTION_DOWN,多个ACTION_MOVE,1个ACTION_UP触发
	//参数解释
	//e1:第1个ACTION_DOWN MotionEvent
	//e2:最后一个ACTION_MOVE MotionEvent
	//velocityX:X轴上的移动速度，像素/秒
	//velocityY:Y轴上的移动速度，像素/秒
	//触发条件：X轴的坐标位移大于FLING_MIN_DISTANCE,且移动速度大于FLING_MIN_VELOCITY个像素/秒
	public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
			float velocityY) {
		// TODO Auto-generated method stub
		if(e1.getX()-e2.getX()>120){
			//Fling left
			Toast.makeText(this, "Fling Left",Toast.LENGTH_SHORT).show();
			this.flipper.setInAnimation(AnimationUtils.loadAnimation(this, R.anim.push_left_in));
			this.flipper.setOutAnimation(AnimationUtils.loadAnimation(this, R.anim.push_left_out));
			this.flipper.showNext();
			return true;
		}else if(e1.getX() - e2.getX() < -120){
			//Fling right
			Toast.makeText(this, "Fling Right",Toast.LENGTH_SHORT).show();
			this.flipper.setInAnimation(AnimationUtils.loadAnimation(this, R.anim.push_right_in));
			this.flipper.setOutAnimation(AnimationUtils.loadAnimation(this, R.anim.push_right_out));
			this.flipper.showPrevious();
			return true;
		}
		return false;
	}

	//用户长按触摸屏，由多个MotionEvent ACTION_DOWN触发
	public void onLongPress(MotionEvent e) {
		// TODO Auto-generated method stub
		
	}

	//用户按下触摸屏，并拖动，由1个Motion ACTION_DOWN,多个ACTION_MOVE触发
	public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
			float distanceY) {
		// TODO Auto-generated method stub
		return false;
	}

	//用户轻触触摸屏，尚未松开或拖动，由一个MotionEvent ACTION_DOWN触发
	public void onShowPress(MotionEvent e) {
		// TODO Auto-generated method stub
		
	}

	//用户（轻触触摸屏后）松开，由一个MotionEvent ACTION_UP触发
	public boolean onSingleTapUp(MotionEvent e) {
		// TODO Auto-generated method stub
		return false;
	}
}