position view in relativelayout runtime

问题

i want to add a view to a relativelayout. this view must be added to a specified position.

i have this:

    int x = ...;
    int y = ...;
    button.setOnTouchListener(new OnTouchListener() {
        public boolean onTouch(View v, MotionEvent event) {
            int x = (int) event.getRawX();
            int y = (int) event.getRawY();
            v.layout(x, y, x + v.getWidth(), y + v.getHeight());
            return true;
        }
    });
    relativelayout.addView(button);
    button.layout(x, y, x + button.getWidth(), y + button.getHeight());

the ontouchlistener works great.. the view stays with my finger. however the startpostion is always 0, 0... it doesn't matter what my x and y is.

anyone a idee?

回答1:

i have a workaround.

RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);
lp.addRule(RelativeLayout.ALIGN_PARENT_TOP);
lp.leftMargin = x;
lp.topMargin = y;
relativelayout.addView(tmpTextButtonView, lp);

it is not great to use margin for positioning floating views. however it works for me.

回答2:

You might want to try setting the position of your button before you add it to the parent view. So just swap these two lines:

relativelayout.addView(button);
button.layout(x, y, x + button.getWidth(), y + button.getHeight());

to be this:

button.layout(x, y, x + button.getWidth(), y + button.getHeight());
relativelayout.addView(button);

来源：https://stackoverflow.com/questions/8477164/position-view-in-relativelayout-runtime