如何在底部检测滚动nestedscrollview android的位置？

Question

我只是想在底部检测滚动nestedscrollview android的位置,以及调用函数.我的代码是:

scroll.getViewTreeObserver()
      .addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
           @Override
           public void onScrollChanged() {
               int totalHeight = scroll.getChildAt(0).getHeight();
               int scrollY = scroll.getScrollY();
               Log.v("position", "totalHeight=" + totalHeight + "scrollY=" + scrollY);
               if (scrollY==totalHeight) {
                   getPlaylistFromServer("more");
               }
           }
      });

但总高度与MAX ScrollY不同.怎么解决？

Answer 1

设置setOnScrollChangeListener在NestedScrollViewPARAMS获得

• NestedScrollView v(带滚动的父级)
• int scrollY
• int oldScrollY

要检测偏移是否在底部,有必要获取内容高度的值v.getChildAt(0).getMeasuredHeight()并将当前滚动与父项的高度进行比较,如果您具有相同的值,则表示它已到达结尾.

您可以使用父视图获取高度 v.getMeasuredHeight()

NestedScrollView scroller = (NestedScrollView) findViewById(R.id.myScroll);

if (scroller != null) {

    scroller.setOnScrollChangeListener(new NestedScrollView.OnScrollChangeListener() {
        @Override
        public void onScrollChange(NestedScrollView v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {

            if (scrollY > oldScrollY) {
                Log.i(TAG, "Scroll DOWN");
            }
            if (scrollY < oldScrollY) {
                Log.i(TAG, "Scroll UP");
            }

            if (scrollY == 0) {
                Log.i(TAG, "TOP SCROLL");
            }

           if (scrollY == ( v.getMeasuredHeight() - v.getChildAt(0).getMeasuredHeight() )) {
               Log.i(TAG, "BOTTOM SCROLL");
           }
       }
    });
}

Answer 2

我知道现在已经很晚了..试试这种方式.

scroll.getViewTreeObserver().addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
    @Override
    public void onScrollChanged() {
            View view = (View) scroll.getChildAt(scroll.getChildCount() - 1);

            int diff = (view.getBottom() - (scroll.getHeight() + scroll
                    .getScrollY()));

            if (diff == 0) {
                getPlaylistFromServer("more");
            }          
    }
});

快乐编码..

Answer 3

Webserve 的回答是正确的，但它需要在 onScrollChange（覆盖方法）中进行一些更改，如下所示：

if (scrollY === v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight()) {
   // end of the scroll view
}

科特林：

if (scrollY == v.getChildAt(0).measuredHeight - v.measuredHeight) {
    // end of the scroll view
}

Answer 4

  @Override
public void onScrollChange(NestedScrollView nestedScrollView, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
    if (nestedScrollView.getChildAt(nestedScrollView.getChildCount() - 1) != null) {
        if ((scrollY >= (nestedScrollView.getChildAt(nestedScrollView.getChildCount() - 1).getMeasuredHeight() - nestedScrollView.getMeasuredHeight())) &&
                scrollY > oldScrollY) {
            LogsUtils.INSTANCE.makeLogD(">onScrollChange>", ">>BOTTOm");
        }

    }
}

它对我有用， 来源

Answer 5

这对我有用：

nestedScroll.setOnScrollChangeListener(new NestedScrollView.OnScrollChangeListener() {
        @Override
        public void onScrollChange(NestedScrollView v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {

            if (v.getChildAt(0).getBottom()<=(nestedScroll.getHeight()+scrollY)) {
                System.out.println("End of NestedScrollView");
            }

        }
    });

基本上，我们在nestedScrollView中添加许多视图，但以单一视图的形式将它们包装在一起。因此，childCount 将始终为 1，其索引为 0。因此，用于v.getChildAt(0).getBottom()确定其底部。现在，nestedScroll.getHeight()返回以像素为单位的高度，并且 ,scrollY将返回当前垂直原点。因此，每次到达 NestedScrollView 的底部时，上述条件都会成立。

if (v.getChildAt(0).getBottom()==(nestedScroll.getHeight()+nestedScroll.getScrollY()))

这只能工作一段时间......因此，不要以这种方式使用它。