Question

我将以下代码放在doInBackground()的另一个AsyncTask中，其中HttpPostHandler包含另一个AsyncTask。然后handler.get()继续加载。
任何人对此有任何想法？
这是关于线程的问题???

代码：

@Override
    protected Void doInBackground(Void... params) {
        try {
                champ = Utility.getCounter("test");

                this.wait(3);
                }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        return null;
    }

在实用程序中：

public static int getCounter(String code) {
    HttpPostHandler handler = new HttpPostHandler();
    try {
        handler.execute(counter_URL + code);
        handler.get();
    } catch (InterruptedException e) {
        e.printStackTrace();
    } catch (ExecutionException e) {
        e.printStackTrace();
    }
    String html = handler.getResultJSONString();
    TagNode tagNode;

    ...
}

以下是HttpPostHandler AsyncTask

    public class HttpPostHandler extends AsyncTask<String, Void, String> {

        private String url;
        private String resultJSONString=null;
        private JSONObject resultJSON;

        public String getResultJSONString() {
            return resultJSONString;
        }

        public void setResultJSONString(String resultJSONString) {
            this.resultJSONString = resultJSONString;
        }

        private static String toUTF8(InputStream is){
            //InputStream is = resEntity.getContent();
            InputStreamReader isr = null;
            StringBuffer buffer = new StringBuffer();
            try {
                isr = new InputStreamReader(is, "utf-8");
                Reader in = new BufferedReader(isr);
                int ch;
                while((ch = in.read()) != -1){
                    buffer.append((char)ch);
                }
                isr.close();
                is.close();
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            } catch (IOException e){
                e.printStackTrace();
            }
            return buffer.toString();
        }

        @Override
        protected String doInBackground(String... params) {
                String result = "";
                DefaultHttpClient client = new DefaultHttpClient();
                try {
                    HttpGet get = new HttpGet(params[0]);
                    HttpResponse response = client.execute(get); 
                    Log.d("danny", "response = "+response);
                    HttpEntity resEntity = response.getEntity();
                    if (resEntity != null) {
                        result = toUTF8(resEntity.getContent());
                    }

                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    client.getConnectionManager().shutdown();
                }
                setResultJSONString(result);
                return result;
        }

        @Override
        protected void onPostExecute(String result) {
            // TODO Auto-generated method stub
            super.onPostExecute(result);
            resultJSONString = result;
        }
    }

Answer 1

如果您在API 11（3.0）或更高版本中运行，则可以将handler.execute(counter_URL + code);更改为handler.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, counter_URL + code);

这允许同时运行多个AsyncTasks。

Answer 2

在doinbackground（）中使用asynctask类的发布进度方法而不是直接调用“handler.execute”。

在onprogressupdate（）中调用“handler.execute”并在doInBackground中调用发布进度。

Answer 3

以下是发布进度的示例：

private class DownloadFilesTask extends AsyncTask<URL, Integer, Long> {
 protected Long doInBackground(URL... urls) {
     int count = urls.length;
     long totalSize = 0;
     for (int i = 0; i < count; i++) {
         totalSize += Downloader.downloadFile(urls[i]);
         publishProgress((int) ((i / (float) count) * 100));
         // Escape early if cancel() is called
         if (isCancelled()) break;
     }
     return totalSize;
 }

 protected void onProgressUpdate(Integer... progress) {
     setProgressPercent(progress[0]);
 }

 protected void onPostExecute(Long result) {
     showDialog("Downloaded " + result + " bytes");
 }

}

如果对您有帮助，请投票或标记为真。

异步任务中的异步

3 个答案: