android - 在异步任务调用期间不显示进度对话框

Question

好的，所以我正在尝试获取一个进度对话框，以显示何时从 Internet 下载数据并将其应用于 UI。我的 asynctask 工作正常，它运行了所有步骤，但它从未显示过对话框。我不知道我在这里做错了什么，我几乎碰壁了。我什至尝试将异步任务放入新的可运行线程中并像那样运行它，但也没有显示对话框。我这样调用异步任务

    new runningMan().execute();

这是我要运行的代码。

private class runningMan extends AsyncTask<Void, Void, Integer>
{

    @Override
    protected void onPreExecute() {
        super.onPreExecute();

        Log.d("Runningman: ", "Started running");
        //this method will be running on UI thread
        progress = ProgressDialog.show(PromotionMain.this, "Loading", "PleaseWait", true);

    }
    @Override
    protected Integer doInBackground(Void... params) {
        //parse the JSON string
        JSONParser jp = new JSONParser();
        try {
            Log.d(username , password);
            jp.parsesData(promos, myJson, pictureArray, pathArray, labelArray);
            Log.d("Runningman: ", "Finished parsing");
        } catch (IOException e) {
            e.printStackTrace();
        }

        return 1;
    }
    @Override
    protected void onPostExecute(Integer result) {
        super.onPostExecute(result);
        ArrayList<ListItem> listData = getListData();
        fillListView(listData);
        Log.d("Runningman: ", "Finished runing");
        //this method will be running on UI thread
        progress.dismiss();
    }

}

感谢您对此的任何帮助。

Answer 1

调用“super.onPreExecute();”和“super.onPostExecute(结果)；”在您的进度对话框代码之后。或者更好的是，摆脱它们(如果您没有调用它们的理由)。

使用以下代码:

private class runningMan extends AsyncTask<Void, Void, Integer>
{

    @Override
    protected void onPreExecute() {

        Log.d("Runningman: ", "Started running");
        //this method will be running on UI thread
        progress = ProgressDialog.show(PromotionMain.this, "Loading", "PleaseWait", true);
        super.onPreExecute();

    }
    @Override
    protected Integer doInBackground(Void... params) {
        //parse the JSON string
        JSONParser jp = new JSONParser();
        try {
            Log.d(username , password);
            jp.parsesData(promos, myJson, pictureArray, pathArray, labelArray);
            Log.d("Runningman: ", "Finished parsing");
        } catch (IOException e) {
            e.printStackTrace();
        }

        return 1;
    }
    @Override
    protected void onPostExecute(Integer result) {
        ArrayList<ListItem> listData = getListData();
        fillListView(listData);
        Log.d("Runningman: ", "Finished runing");
        //this method will be running on UI thread
        progress.dismiss();
        super.onPostExecute(result);
    }

}