public void setFillViewport(boolean fillViewport) {
        if (fillViewport != mFillViewport) {
            mFillViewport = fillViewport;
            requestLayout();
        }
    }
Set whether this ScrollView should stretch its content height to fill the viewport or not.

@param fillViewport True to stretch the content's height to the viewport's
       boundaries, false otherwise.

@attr name android:fillViewport
app/src/main/java/home/smart/fly/animations/widget/NestedScrollView.java