最近做專案用到了滑動自動播放，下面是原理大家借鑑一下：

關鍵程式碼
1.監聽滾動事件
首先要給listview新增setOnScrollListener監聽,注意這個監聽在recyclerView上是addOnScrollListener，也就是說下面程式碼同時支援recyclerView。

public int firstVisible=0,visibleCount=0, totalCount=0;
 videoList.setOnScrollListener(new AbsListView.OnScrollListener() {
    @Override
    public
 
 void onScrollStateChanged(AbsListView view, int scrollState) {
      switch (scrollState) {

        case AbsListView.OnScrollListener.SCROLL_STATE_FLING:
          Log.e("videoTest", "SCROLL_STATE_FLING");
          break;

        case AbsListView.OnScrollListener.SCROLL_STATE_IDLE:
          Log.e("videoTest"
 
, "SCROLL_STATE_IDLE");
          autoPlayVideo(view);
          break;

        case AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL:
          Log.e("videoTest", "SCROLL_STATE_TOUCH_SCROLL");
          break;

        default:
          break;
      }
    }  
    @Override
    public void onScroll
 
(AbsListView view, int firstVisibleItem,
               int visibleItemCount, int totalItemCount) {
      // firstVisibleItem  當前第一個可見的item
      // visibleItemCount  當前可見的item個數
      if (firstVisible == firstVisibleItem) {
        return;
      }
      firstVisible = firstVisibleItem;
      visibleCount = visibleItemCount;
      totalCount = totalItemCount;
    }
  });

監聽裡會有兩個方法，我們用onScroll方法記錄 當前第一個可見Item，以及可見Item總數，用onScrollStateChanged來監聽手滑動螢幕的整個過程。 當onScrollStateChanged 中的scrollState欄位值等於SCROLL_STATE_IDLE 時，代表本次滑動完畢並停止滾動。

**SCROLL_STATE_TOUCH_SCROLL 手指觸屏拉動準備滾動，只觸發一次
SCROLL_STATE_FLING 持續滾動開始，只觸發一次
SCROLL_STATE_IDLE 整個滾動事件結束，只觸發一次**

2.處理視訊邏輯

void autoPlayVideo(AbsListView view){
  Log.e("videoTest", "firstVisiblePos = " + firstVisible + "visibleItemCount = " + visibleCount);
  for (int i = 0; i < visibleCount; i++) {
    if (view!=null&&view.getChildAt(i)!=null&&view.getChildAt(i).findViewById(R.id.videoplayer) != null) {
      JCVideoPlayerStandard videoPlayerStandard1 = (JCVideoPlayerStandard) view.getChildAt(i).findViewById(R.id.videoplayer);
      Rect rect = new Rect();
      videoPlayerStandard1.getLocalVisibleRect(rect);
      int videoheight3 = videoPlayerStandard1.getHeight();
      Log.e("videoTest","i="+i+"==="+"videoheight3:"+videoheight3+"==="+"rect.top:"+rect.top+"==="+"rect.bottom:"+rect.bottom);
      if (rect.top==0&&rect.bottom==videoheight3)
      {
        if (videoPlayerStandard1.currentState == JCVideoPlayer.CURRENT_STATE_NORMAL || videoPlayerStandard1.currentState == JCVideoPlayer.CURRENT_STATE_ERROR) {
          Log.e("videoTest", videoPlayerStandard1.currentState + "======================performClick======================");
          videoPlayerStandard1.startButton.performClick();
          VPApplication.instance.VideoPlaying=videoPlayerStandard1;
        }
        return;
      }

    }
  }
  Log.e("videoTest", "======================releaseAllVideos=====================");
  JCVideoPlayer.releaseAllVideos();
  VPApplication.instance.VideoPlaying=null;
}

首先是根據總數迴圈判斷 Item 是否有視訊，如果有再利用Rect類獲取檢視在螢幕座標中的可視區域。