以自定义ImageView为例:
/** * 可拖拽ImageView * Created by admin on 2017/2/21. */ public class FloatingImageView extends ImageView{ public FloatingImageView(Context context) { super(context); } public FloatingImageView(Context context, AttributeSet attrs) { super(context, attrs); } public FloatingImageView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); } @TargetApi(Build.VERSION_CODES.LOLLIPOP) public FloatingImageView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); } int startX; int startY; int left; int top; int[] temp = new int[]{ 0, 0 }; @Override public boolean onTouchEvent(MotionEvent event) { boolean isMove = false; int x = (int) event.getRawX(); int y = (int) event.getRawY(); switch (event.getAction()){ case MotionEvent.ACTION_DOWN: // touch down so check if the startX = x; startY = y; temp[0] = (int) event.getX(); temp[1] = y - getTop(); break; case MotionEvent.ACTION_MOVE: // touch drag with the ball left = x - temp[0]; top = y - temp[1]; if(left < 0){//控制左边界不超出 left = 0; } layout(left, top, left + getWidth(),top + getHeight());//自由拖拽 break; case MotionEvent.ACTION_UP: if (Math.abs(x - startX) > 2 || Math.abs(y - startY) > 2){//判断是否移动,再一定范围内不算是移动,解决触发事件冲突 //将最后拖拽的位置定下来,否则页面刷新渲染后按钮会自动回到初始位置 //注意父容器 RelativeLayout.LayoutParams lp = (RelativeLayout.LayoutParams) getLayoutParams(); lp.setMargins(left, top,0,0); setLayoutParams(lp); //确定是拖拽 isMove = true; } break; } return isMove ? true : super.onTouchEvent(event); } }
原文地址:https://www.cnblogs.com/xgjblog/p/8719508.html
时间: 2024-11-05 14:58:23