在runOnUiThread里面更新adapter有BUG

Question

SpreadService.getAdMsgList(id, pageNumber + "", new ChatCallBack() {

    @Override
    public void onSuccess(AppResult result) {
        List<DynamicdetailBean> list = JSONArray.parseArray(result
                .getData().toString(), DynamicdetailBean.class);
        if (list != null && list.size() > 0) {
            if (isFirstLoading) {
                datalist.clear();
                datalist.addAll(list);
            } else {
                datalist.addAll(list);
            }
        } 

//以上是oncreate()方法里面调用的方法，datalist也是在oncreate中初始化的集合，在service里面新建的一个工作线程执行http访问，成功后回调处理数据方法，具体太多，不列出，返回数据都正常，
//关键是下面的代码：

MainActivity.this.runOnUiThread(new Runnable() {
@Override
public void run() {
if (isFirstLoading) { //是否第一次加载
isFirstLoading = false;
adapter = new ListAdapater(MainActivity.this,
1, datalist);
listView.setAdapter(adapter);
} else {
//TODO
adapter.notifyDataSetChanged();
}
footLoading.setVisibility(View.GONE);
isLoading = false;
}
});
//adapter是继承arrayadapter,就职声明了控件，每怎么重写方法，getview,class Viewholder什么的就不列出来了，如下:
private class ListAdapater extends ArrayAdapter {
private LayoutInflater inflater;
private SpannableStringBuilder builder;
private Context context;
private List list;

    // TODO
    public ListAdapater(Context context, int res,
            List<DynamicdetailBean> list) {
        super(context, res, list);
        this.inflater = LayoutInflater.from(context);
        this.context = context;
        this.list = list;
        builder = new SpannableStringBuilder("回复");
        ForegroundColorSpan yellowSpan = new ForegroundColorSpan(context
                .getResources().getColor(R.color.red_text));
        builder.setSpan(yellowSpan, 0, builder.length(),
                Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
    }
}   
但是每次从其他Activity跳转过来后，有时正常显示更新listview内容，有时就报错了：说listview没收到notification,如下：

但是如果不用runOnUiThread,改成用handler发消息就不会出错：
handler.sendMessage(handler.obtainMessage(1, datalist));
Handler handler = new Handler(){
    public void handleMessage(android.os.Message msg) {
        datalist = (List<DynamicdetailBean>) msg.obj;
        switch(msg.what){
        case 1:
            if (isFirstLoading) {
                isFirstLoading = false;
                adapter = new ListAdapater(OfficialActivity.this,
                        1, datalist);
                listView.setAdapter(adapter);
            } else {
                //TODO
                adapter.notifyDataSetChanged();
            }
            footLoading.setVisibility(View.GONE);
            isLoading = false;
            break;
        }
    };
};
这是为什么呢，runOnUiThread有限制条件么？还请各位大神指点啊！！！

Answer 1