Question

How can you change the coordinates of a view while its animating? For instance, if I’m doing a translation of a View on the screen from left to right, I want the View to push everything to the right of it as its moving?

public Animation expandHiddenPanel(final View v, final boolean expand) {
    panelExpanded = expand;
    v.measure(MeasureSpec.makeMeasureSpec(200, MeasureSpec.AT_MOST), 
              MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));

    final int initialWidth = v.getMeasuredWidth();
    Log.i("test", "initialWidth = " + initialWidth);

    v.getLayoutParams().width = 0;
    v.setVisibility(View.VISIBLE);

    Animation a = new Animation() {
        @Override
        protected void applyTransformation(float interpolatedTime, Transformation t) {
            int newWidth;

            if (expand) {
                newWidth = (int)(initialWidth * interpolatedTime);
                Log.i("test", "new Width = " + newWidth);
            }
            else {
                newWidth = (int)(initialWidth * (1 - interpolatedTime));
                Log.i("test", "new Width = " + newWidth);
            }

            v.getLayoutParams().width = newWidth;
            v.requestLayout();
        }

        @Override
        public boolean willChangeBounds() {
            return true;
        }
    };

    a.setInterpolator(new AccelerateInterpolator());
    a.setDuration(2500);
    a.setFillAfter(true);
    v.startAnimation(a);

    return a;
}

Answer 1

I fixed this by overlaying the main layout over my panel, placing the button in the upper left hand corner of my main layout, and changing the code i posted above to pad the left margin of my main layout to reveal the panel.

To get the sliding drawer effect, I changed the panel’s visibility and applied a translate animation that ran for the same duration and used the same interpolator.