如何通过移动手指来改变活动？

wdfeww 发表于 Dev

wdfeww

我想寻求帮助。您能给我一些建议，如何通过移动手指来改变活动。（如图所示）谢谢您的回答

在此处输入图片说明

图片：https : //imageshack.us/download/661/xaxrzF.png

kashif181

您可以使用GestureDetector做到这一点，以下是工作代码用您自己的活动替换左右活动

public class MainActivity extends Activity {
  private GestureDetector gesture;
  
  @Override
  public void onCreate(Bundle savedInstanceState) 
  {
    gesture = new GestureDetector(new SwipeGestureDetector());
  }


  @Override
  public boolean onTouchEvent(MotionEvent event) 
  {
    if (gesture.onTouchEvent(event)) 
	{
      return true;
    }
    return super.onTouchEvent(event);
  }

  private void onLeft() 
  {
    Intent myIntent = new Intent(MainActivity.this, LeftActivity.class);
	startActivity(myIntent);
  }

  private void onRight() 
  {
    Intent myIntent = new Intent(MainActivity.this, RightActivity.class);
	startActivity(myIntent);
  }

  // Private class for gestures
  private class SwipeGestureDetector  extends SimpleOnGestureListener 
	{
		private static final int SWIPE_MIN_DISTANCE = 120;
		private static final int SWIPE_MAX_OFF_PATH = 200;
		private static final int SWIPE_THRESHOLD_VELOCITY = 200;

		@Override
		public boolean onFling(MotionEvent e1, MotionEvent e2,float velocityX, float velocityY) 
		{
			try 
			{
				float diffAbs = Math.abs(e1.getY() - e2.getY());
				float diff = e1.getX() - e2.getX();

				if (diffAbs > SWIPE_MAX_OFF_PATH)
				return false;
        
				// Left swipe
				if (diff > SWIPE_MIN_DISTANCE&& Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) 
				{
					MainActivity.this.onLeft();
				} 
				// Right swipe
				
				else if (-diff > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) 
				{
					MainActivity.this.onRight();
				}
			} 
			catch (Exception e) 
			{
				Log.e("MainActivity", "Error on gestures");
			}
			return false;
		}
	}
}