Android使用ViewPager加载图片和轮播视频

public void initData() {  //把聊天界面的图片和视频找出来，并加到数组中，并在  //并根据传进来的position来找到视频或图片在数组中的位置  for (int i = 0; i < MsgCount; i++) {   Msg1 msg1 = fridenMessages.MessageList.get(i);   if (msg1.getMsg().startsWith(ChatUtil.TAG_IMAGE) || msg1.getMsg().startsWith(ChatUtil.TAG_VIDEO)) {    ImageUrl.add(msg1.getMsg());    //查看消息postion对应的图片位置    if (position == i) {     position = ImageUrl.size() - 1;     Log.i("TAG", "position=" + position);    }   }  }  Log.i("TAG", "position=" + position);  //把要用到的view加到viewList中  for (int i = 0; i < ImageUrl.size(); i++) {   if (ImageUrl.get(i).startsWith(ChatUtil.TAG_IMAGE)) {    PhotoView photoView = new PhotoView(context);    viewList.add(photoView);   } else if (ImageUrl.get(i).startsWith(ChatUtil.TAG_VIDEO)) {    View view1 = LayoutInflater.from(context).inflate(R.layout.activity_video_player, null);    SurfaceVideoView videoView = (SurfaceVideoView) view1.findViewById(R.id.videoview);    int screenWidth = getScreenWidth((Activity) context);    int videoHight = (int) (screenWidth / (MediaRecorderBase.SMALL_VIDEO_WIDTH / (MediaRecorderBase.SMALL_VIDEO_HEIGHT * 1.0f)));//    int videoHight = (int) (screenWidth)*4/3;    videoView.getLayoutParams().height = videoHight;    videoView.requestLayout();    View playStatus = view1.findViewById(R.id.play_status);    View loading = view1.findViewById(R.id.loading);    viewList.add(view1);   }  }  adapter = new MyAdapter();  viewPager.setAdapter(adapter);  if (position != -1) {   viewPager.setCurrentItem(position);  } }``` public void initEvent() {  //给viewPager设置监听  viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {   @Override   public void onPageSelected(int arg0) {    int childCount = viewPager.getChildCount();//viewPager得到页面的数量    //如果不是在原页面，让原来页面的视频停止播放    if(position != arg0){     position=arg0;     StopVideo();    }    // 遍历当前所有加载过的PhotoView，恢复所有图片的默认状态    for (int i = 0; i < childCount; i++) {     View childAt = viewPager.getChildAt(i);     try {      if (childAt != null && childAt instanceof PhotoView) {       PhotoView photoView = (PhotoView) childAt;       photoView.setOnPhotoTapListener(new PhotoViewAttacher.OnPhotoTapListener() {        @Override        public void onPhotoTap(View view, float x, float y) {         finish();        }        @Override        public void onOutsidePhotoTap() {        }       });      }     } catch (Exception e) {      e.printStackTrace();     }    }    if (ImageUrl.get(position).startsWith(ChatUtil.TAG_VIDEO)) {     String body = ChatApplication.dbHelper.getVideoSdPath(ImageUrl.get(position));     String url[] = ImageUrl.get(position).substring(ChatUtil.TAG_VIDEO.length()).split("&&");     View childAt = viewList.get(arg0);     SurfaceVideoView videoView = (SurfaceVideoView) childAt.findViewById(R.id.videoview);     mVideoView = videoView;     mPlayerStatus = childAt.findViewById(R.id.play_status);     mLoading = childAt.findViewById(R.id.loading);     Log.i("TAG", "videoUrl=" + body);     setVideoUrl(body, url);     //延迟50ms，让播放器播放视频时，让它暂停     Handler handler = new Handler();     handler.postDelayed(new Runnable() {      @Override      public void run() {       StopVideo();      }     }, 50);    }   }   @Override   public void onPageScrolled(int arg0, float arg1, int arg2) {    // TODO Auto-generated method stub   }   @Override   public void onPageScrollStateChanged(int arg0) {    // TODO Auto-generated method stub   }  }); } public class MyAdapter extends PagerAdapter {  @Override  public int getCount() {   return ImageUrl.size();  }  @Override  public View instantiateItem(ViewGroup container, int pos) {   Log.i("TAG", "pos=" + pos);   if (ImageUrl.get(pos).startsWith(ChatUtil.TAG_IMAGE)) {    PhotoView photoView = (PhotoView) viewList.get(pos);    container.addView(photoView, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);    String body[] = ImageUrl.get(pos).substring(ChatUtil.TAG_IMAGE.length()).split("&&");    Log.i("TAG", "<IMAGE>=" + body[0]);    ImageLoader.getInstance().displayImage(body[0], photoView);    photoView.setScaleType(ImageView.ScaleType.FIT_CENTER);//设置图片显示为充满全屏    photoView.setOnPhotoTapListener(new PhotoViewAttacher.OnPhotoTapListener() {     @Override     public void onPhotoTap(View view, float x, float y) {      finish();     }     @Override     public void onOutsidePhotoTap() {     }    });    //   photoView.setOnLongClickListener(longClickListener);   } else if (ImageUrl.get(pos).startsWith(ChatUtil.TAG_VIDEO)) {     View view1 = viewList.get(pos);    SurfaceVideoView VideoView = (SurfaceVideoView) view1.findViewById(R.id.videoview);    int screenWidth = getScreenWidth((Activity) context);    int videoHight = (int) (screenWidth / (MediaRecorderBase.SMALL_VIDEO_WIDTH / (MediaRecorderBase.SMALL_VIDEO_HEIGHT * 1.0f)));//    int videoHight = (int) (screenWidth)*4/3;    VideoView.getLayoutParams().height = videoHight;    VideoView.requestLayout();    View PlayerStatus = view1.findViewById(R.id.play_status);    View Loading = view1.findViewById(R.id.loading);    VideoView.setOnPreparedListener(ShowBigPictureActivity.this);    VideoView.setOnPlayStateListener(ShowBigPictureActivity.this);    VideoView.setOnErrorListener(ShowBigPictureActivity.this);    VideoView.setOnClickListener(ShowBigPictureActivity.this);    VideoView.setOnInfoListener(ShowBigPictureActivity.this);    VideoView.setOnCompletionListener(ShowBigPictureActivity.this);    container.addView(view1, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);    String body = ChatApplication.dbHelper.getVideoSdPath(ImageUrl.get(pos));    String url[] = ImageUrl.get(pos).substring(ChatUtil.TAG_VIDEO.length()).split("&&");    //找到是点击聊天界面哪个视频进来的，将局部成员，付给类成员    if(pos==position) {     mVideoView = VideoView;     mPlayerStatus=PlayerStatus;     mLoading=Loading;     setVideoUrl(body,url);    }   }   return viewList.get(pos);  }  @Override  public void destroyItem(ViewGroup container, int position, Object object) {   container.removeView((View) object);  }  @Override  public boolean isViewFromObject(View view, Object object) {   return view == object;  } }以下是控制视频播放的接口： public void onCompletion(MediaPlayer mp) {  onStateChanged(false); } @Override public boolean onError(MediaPlayer mp, int what, int extra) {  return false; } @Override public boolean onInfo(MediaPlayer mp, int what, int extra) {  switch (what) {   case MediaPlayer.MEDIA_INFO_BAD_INTERLEAVING:    // 音频和视频数据不正确    ConfigUtil.showShort(context, "视频数据不正确！");    break;   case MediaPlayer.MEDIA_INFO_BUFFERING_START:    if (!isFinishing())     mVideoView.pause();    break;   case MediaPlayer.MEDIA_INFO_BUFFERING_END:    if (!isFinishing())     mVideoView.start();    break;   case MediaPlayer.MEDIA_INFO_VIDEO_RENDERING_START:    if (DeviceUtils.hasJellyBean()) {     mVideoView.setBackground(null);    } else {     mVideoView.setBackgroundDrawable(null);    }  break; } return false;} @Override public void onStateChanged(boolean isPlaying) {  mPlayerStatus.setVisibility(isPlaying ? View.GONE : View.VISIBLE); } @Override public void onPrepared(MediaPlayer mp) {  mVideoView.setVolume(SurfaceVideoView.getSystemVolumn(this));  mVideoView.start();  mLoading.setVisibility(View.GONE); }