Question

我在Custom Adapter类中使用异步调用来在Listview中加载图像。但是，直到我轻轻向上/向下滚动图像才会显示。请让我知道可能是什么原因。谢谢你的帮助。

private class LoadImage extends AsyncTask<Void, Void, Void>
{ 
    private String fileName = null;
    private ImageView imgViewToLoad = null;

    LoadImage(String fileName, ImageView imgViewToLoad)
    {
        this.fileName = fileName;
        this.imgViewToLoad = imgViewToLoad;
    }

@Override
protected Void doInBackground(Void... args)
{   
    return null;
}

//This is executed on main UI thread
@Override
protected void onPostExecute(Void result) {

    super.onPostExecute(result);
    Utils.mImageFetcher.loadImage(fileName, imgViewToLoad);
}
}


This is in my getView()
----------------------

ViewHolderIncomingImg holderInImg = null;
if (null != convertView && 
  (convertView.getTag() instanceof ViewHolderIncomingImg && !isFirstMsg))
{
  holderInImg = (ViewHolderIncomingImg) convertView.getTag();
  if (!multiSelectionMode)
  {
      if (!mSelectedItemsIds.get(position) && convertView.isActivated())
          convertView.setActivated(false);
  }
}
else
{
  convertView = mInflater.inflate(R.layout.conv_list_item_incoming_img, parent, false);
  holderInImg = new ViewHolderIncomingImg();

..............

new LoadImage(convRowItems.get(position).getMessage(), holderInImg.image).execute();

Answer 1

由于Listview使用回收其视图的概念。异步调用完成后，图像不会显示。

所以去listview延迟加载方法它会帮助你。

Listview没有加载图像，直到我滚动屏幕

1 个答案: