检测向上滚动在 ListView 中向下滚动 [英] Detect Scroll Up & Scroll down in ListView

问题描述

我有以下要求:

• 首先，从服务器获取第 2 页的数据 &这几项填充在 ListView 中.

考虑到上一页和下一页在场景中可用，已添加以下代码:

Considering that both the prev page & next page are available in a scenario, the following code has been added:

 if(prevPageNo > 0){
    mListViewActual.setOnScrollListener(this);
 }

 if(nextPageNo > 0){
    mListViewActual.setOnScrollListener(this);
 }

我应该设置什么条件来检测向上滚动&向下滚动以下方法:

What conditions should I put to detect scroll up & scroll down on the following methods:

1. void onScroll(AbsListView view, int firstVisibleItem, intvisibleItemCount, int totalItemCount)
2. void onScrollStateChanged(AbsListView view, int scrollState)

动作后:向上滚动&检测到向下滚动，因此将使用上一页或下一页调用服务，以获取要在 Listview 中填充的项目.

After the action: scroll up & scroll down is detected , accordingly a service will be called with either the prev page no or next page no , to fetch the items to be populated in the Listview.

任何输入都会有所帮助.

Any inputs will be helpful.

浏览了以下链接，但没有返回正确的向上滚动/向下滚动操作:

Gone through the following links but its not returning the correct scroll up / scroll down action:

链接 1链接 2

推荐答案

尝试使用 setOnScrollListener 并使用 scrollState 实现 onScrollStateChanged

try using the setOnScrollListener and implement the onScrollStateChanged with scrollState

setOnScrollListener(new OnScrollListener(){
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
      // TODO Auto-generated method stub
    }
    public void onScrollStateChanged(AbsListView view, int scrollState) {
      // TODO Auto-generated method stub
      final ListView lw = getListView();

       if(scrollState == 0) 
      Log.i("a", "scrolling stopped...");


        if (view.getId() == lw.getId()) {
        final int currentFirstVisibleItem = lw.getFirstVisiblePosition();
         if (currentFirstVisibleItem > mLastFirstVisibleItem) {
            mIsScrollingUp = false;
            Log.i("a", "scrolling down...");
        } else if (currentFirstVisibleItem < mLastFirstVisibleItem) {
            mIsScrollingUp = true;
            Log.i("a", "scrolling up...");
        }

        mLastFirstVisibleItem = currentFirstVisibleItem;
    } 
    }
  });

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