Question

我只是想在底部检测滚动nestedscrollview android的位置，以及to call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

在setOnScrollChangeListener参数中设置NestedScrollView以获取

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v.getChildAt(0).getMeasuredHeight()的值并比较当前滚动与父级的高度，如果您具有相同的值，则意味着它已经到了终点。

您可以使用v.getMeasuredHeight()

获取包含父视图的高度

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但是试试这个。

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回答正确，但是需要在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
}

科特琳：

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");
        }

    }
}

它为我工作，Source

Answer 5

对于api <23，您可以添加一个treeObserver.scrollChangeLister存储本地float变量，并检查滚动的方式

示例

public class About extends AppCompatActivity implements 
ViewTreeObserver.OnScrollChangedListener{

private float viewScrolled = 0;

   nestedScrollView.getViewTreeObserver().addOnScrollChangedListener(this);

}

@Override
public void onScrollChanged() {

    if (viewScrolled < nestedScrollView.getScrollY()){
        viewScrolled = nestedScrollView.getScrollY();
        Log.d(TAG, "scrolling up");
    }
    if (viewScrolled > nestedScrollView.getScrollY()){
        viewScrolled = nestedScrollView.getScrollY();
        Log.d(TAG, "scrolling down");
    }
}

Answer 6

Webserve回答正确，但是条件应该是这样

 if (scrollY == (v?.getChildAt(0)?.measuredHeight ?: 0) - (v?.measuredHeight ?: 0)) {
    //at bottom
    }

Answer 7

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内添加了许多视图，但以单视图的形式将它们包装在一起。因此，childCount将始终为1，索引为0。因此，使用v.getChildAt(0).getBottom()来确定其底数。现在，nestedScroll.getHeight()返回以像素为单位的高度，而scrollY将返回当前的垂直原点。因此，每次达到NestedScrollView的底部时，上述条件都成立。

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

这只能工作一段时间...因此，请勿以这种方式使用。

Answer 8

这对我有用！

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



                    if (scrollY == v.getChildAt(0).getMeasuredHeight() - v.getMeasuredHeight()) {
                        Log.d(TAG, "onScrollChange: SRCOLLED ==> scrollY: ======================================> THIS IS THE VERY END ");
                    }

                

            }
        });

如何在底部检测滚动nestedscrollview android的位置？

8 个答案: