android控件拖动，移动、解决父布局重绘时控件回到原点

 

这是主要代码: 保证其params发生改变，相对于父布局的位置就能达到位置移动到原来的位置

// 每次移动都要设置其layout，不然由于父布局可能嵌套listview，当父布局发生改变冲毁（如下拉刷新时）则移动的view会回到原来的位置
RelativeLayout.LayoutParams lpFeedback = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
lpFeedback.leftMargin = v.getLeft();
lpFeedback.topMargin = v.getTop();
lpFeedback.setMargins(v.getLeft(), v.getTop(), 0, 0);
v.setLayoutParams(lpFeedback);

思路是：当view的位置发生改变时，也要相应改变其layoutparams，否则父布局重绘时，由于view的layoutparams没发生改变导致重绘的时候会回到原点，所以只要改变其params就好了

/**
     *
     * @description 设置意见反馈，用以灰度发布
     * @author zhongwr
     * @params
     * @update 2016年1月12日 下午5:36:07
     */
    private ImageView getFeedBackView() {
        ImageView ivFeedback = new ImageView(BaseActivity.this);
        ivFeedback.setImageResource(R.drawable.fuli_feedback);
        RelativeLayout.LayoutParams lpFeedback = new RelativeLayout.LayoutParams(
                RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
        lpFeedback.setMargins(0, 0, 20, 218);
        lpFeedback.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
        lpFeedback.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
        ivFeedback.setLayoutParams(lpFeedback);
        ivFeedback.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {// 意见反馈
                FeedBackActivity.startInstance(BaseActivity.this);
            }
        });
        return ivFeedback;
    }

    private boolean isIntercept = false;
    /** 按下时的位置控件相对屏幕左上角的位置X */
    private int startDownX;
    /** 按下时的位置控件距离屏幕左上角的位置Y */
    private int startDownY;
    /** 控件相对屏幕左上角移动的位置X */
    private int lastMoveX;
    /** 控件相对屏幕左上角移动的位置Y */
    private int lastMoveY;

    /**
     *
     * @description 拖动意见反馈位置
     * @author zhongwr
     * @params
     * @update 2016年1月14日 下午5:08:26
     */
    private void setFeedBackViewDragTouch(ImageView ivFeedBack) {

        ivFeedBack.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {
                int action = event.getAction();
                switch (action) {
                case MotionEvent.ACTION_DOWN:
                    startDownX = lastMoveX = (int) event.getRawX();
                    startDownY = lastMoveY = (int) event.getRawY();
                    break;
                case MotionEvent.ACTION_MOVE:
                    int dx = (int) event.getRawX() - lastMoveX;
                    int dy = (int) event.getRawY() - lastMoveY;

                    int left = v.getLeft() + dx;
                    int top = v.getTop() + dy;
                    int right = v.getRight() + dx;
                    int bottom = v.getBottom() + dy;
                    if (left < 0) {
                        left = 0;
                        right = left + v.getWidth();
                    }
                    if (right > mScreenWidth) {
                        right = mScreenWidth;
                        left = right - v.getWidth();
                    }
                    if (top < 0) {
                        top = 0;
                        bottom = top + v.getHeight();
                    }
                    if (bottom > mScreenHeight) {
                        bottom = mScreenHeight;
                        top = bottom - v.getHeight();
                    }
                    v.layout(left, top, right, bottom);
                    lastMoveX = (int) event.getRawX();
                    lastMoveY = (int) event.getRawY();
                    break;
                case MotionEvent.ACTION_UP:
                    int lastMoveDx = Math.abs((int) event.getRawX() - startDownX);
                    int lastMoveDy = Math.abs((int) event.getRawY() - startDownY);
                    if (0 != lastMoveDx || 0 != lastMoveDy) {
                        isIntercept = true;
                    } else {
                        isIntercept = false;
                    }
                    // 每次移动都要设置其layout，不然由于父布局可能嵌套listview，当父布局发生改变冲毁（如下拉刷新时）则移动的view会回到原来的位置
                    RelativeLayout.LayoutParams lpFeedback = new RelativeLayout.LayoutParams(
                            RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
                    lpFeedback.leftMargin = v.getLeft();
                    lpFeedback.topMargin = v.getTop();
                    lpFeedback.setMargins(v.getLeft(), v.getTop(), 0, 0);
                    v.setLayoutParams(lpFeedback);
                    break;
                }
                return isIntercept;
            }
        });
    }

demo：demo