library/src/main/java/com/github/clans/fab/FloatingActionButton.java
public void setShadowYOffset(int dimenResId) {
        int shadowYOffset = getResources().getDimensionPixelSize(dimenResId);
        if (mShadowYOffset != shadowYOffset) {
            mShadowYOffset = shadowYOffset;
            requestLayout();
            updateBackground();
        }
    }
public void setShadowYOffset(int dimenResId) {
        int shadowYOffset = getResources().getDimensionPixelSize(dimenResId);
        if (mShadowYOffset != shadowYOffset) {
            mShadowYOffset = shadowYOffset;
            requestLayout();
            updateBackground();
        }
    }
Sets the shadow y offset of the <b>FloatingActionButton</b> and invalidates its layout.

@param dimenResId the resource identifier of the dimension