RCRelativeLayout.java 文件源码

@Override protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(w, h, oldw, oldh);
    mLayer = new RectF(0, 0, w, h);
    RectF areas = new RectF();
    areas.left = getPaddingLeft();
    areas.top = getPaddingTop();
    areas.right = w - getPaddingRight();
    areas.bottom = h - getPaddingBottom();
    mClipPath.reset();
    if (mRoundAsCircle) {
        float d = areas.width() >= areas.height() ? areas.height() : areas.width();
        float r = d / 2;
        PointF center = new PointF(w / 2, h / 2);
        mClipPath.addCircle(center.x, center.y, r, Path.Direction.CW);
        mClipPath.moveTo(-mEdgeFix, -mEdgeFix);  // 通过空操作让Path区域占满画布
        mClipPath.moveTo(w + mEdgeFix, h + mEdgeFix);
    } else {
        mClipPath.addRoundRect(areas, radii, Path.Direction.CW);
    }
    Region clip = new Region((int) areas.left, (int) areas.top,
                             (int) areas.right, (int) areas.bottom);
    mAreaRegion.setPath(mClipPath, clip);
}