DepthRendrer.java 文件源码

void setup() {
    getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
        @Override
        public boolean onPreDraw() {
            for (int i = 0; i < getChildCount(); i++) {
                View child = getChildAt(i);
                if (child instanceof DepthLayout) {
                    boolean hasChangedBounds = ((DepthLayout) child).calculateBounds();
                    if (hasChangedBounds)
                        invalidate();
                }
            }
            return true;
        }
    });

    shadowPaint.setColor(Color.BLACK);
    shadowPaint.setAntiAlias(true);
    softShadow = (NinePatchDrawable) getResources().getDrawable(R.drawable.shadow, null);
    roundSoftShadow = getResources().getDrawable(R.drawable.round_soft_shadow, null);
}