手指划动切换Activity

水深无声 2022-10-02 01:50 117阅读 0赞

[2019独角兽企业重金招聘Python工程师标准>>> ][2019_Python_] ![hot3.png][]

以下代码用于Activity之间的划动切换，大概实现原理就是判断手指的划动速度和划动方向以确定向哪个Activity跳转，switchTo\*\*\*Activity（）为Activity的跳转方法

private VelocityTracker velocityTracker;//用于得到手势在屏幕上的滑动速度
    	private static final int VELOCITY = 600;        
            @Override
    	public boolean onTouchEvent(MotionEvent event) {
    		String localClassName = getLocalClassName();//当前所在类名
    		LogUtil.log(TAG, "class Name:"+localClassName);
    		int action = event.getAction();
    		//float x = event.getX();
    		//float y = event.getY();
    		
    		switch (action) {
    		case MotionEvent.ACTION_DOWN:
    			if(velocityTracker == null){
    				velocityTracker = VelocityTracker.obtain();//取得手势在屏幕上的滑动速度
    				velocityTracker.addMovement(event);
    			}			
    			//lastMotionX = x;
    			
    			break;
    		
    		case MotionEvent.ACTION_MOVE:
    			//int deltaX = (int) (lastMotionX - x);
    			if(velocityTracker != null){
    				velocityTracker.addMovement(event);
    			}
    			//lastMotionX = x;
    			break;
    			
    		case MotionEvent.ACTION_UP:
    			
    			int velocityX = 0;
    			if(velocityTracker != null){
    				velocityTracker.addMovement(event);
    				velocityTracker.computeCurrentVelocity(1000);//计算每秒滑动多少个像素
    				velocityX = (int) velocityTracker.getXVelocity();//最后计算检索X速度
    			}
    			
    			if(velocityX > VELOCITY ){
    				if("ui.MainActivity".equals(localClassName)){
    					switchToTvLiveActivity();
    				}else if("ui.LocalMediaActivity".equals(localClassName)){
    					switchToMainActivity();
    				}else if("ui.NetMediaActivity".equals(localClassName)){
    					switchToLocalMediaActivity();
    				}else if("ui.TvLiveActivity".equals(localClassName)){
    					switchToNetMediaActivity();
    				}
    			} else if(velocityX < -VELOCITY ){
    				if("ui.MainActivity".equals(localClassName)){
    					switchToLocalMediaActivity();
    				}else if("ui.LocalMediaActivity".equals(localClassName)){
    					switchToNetMediaActivity();
    				}else if("ui.NetMediaActivity".equals(localClassName)){
    					switchToTvLiveActivity();
    				}else if("ui.TvLiveActivity".equals(localClassName)){
    					switchToMainActivity();
    				}
    			}
    			
    			if(velocityTracker != null){
    				velocityTracker.recycle();//回收
    				velocityTracker = null;
    			}
    			
    			break;
    		}
    		
    		return true;
    	}

转载于:https://my.oschina.net/AlexZhuang/blog/57768

[2019_Python_]: https://my.oschina.net/u/2663968/blog/3061697
[hot3.png]: /images/20220113/a7c38c2081bb4e50a2e68179a839aa41.png