如何才能使页脚可见，只有当ScrollView向下滚动

Question

如果向下滚动ScrollView，则必须显示页脚。如果它向上滚动，那么页脚必须禁用。怎么做这种事?

Answer 1

有人已经在评论中发布了这个，但无论如何这里是。

@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
        View view = (View) getChildAt(getChildCount()-1);
        int diff = (view.getBottom()-(getHeight()+getScrollY()));
        if( diff <= 0 ){ 
            yourFooter.setVisibility(View.GONE);
        }
        else{
            yourFooter.setVisibility(View.VISIBLE);
        }
        super.onScrollChanged(l, t, oldl, oldt);
}

扩展ScrollView，然后重写onScrollChanged方法