Android如何实现AsyncTask的并行执行

我需要允许多个AsyncTask同时运行。 这是我的AsyncTask：

private void callAPI(String user_id) { new AsyncTask() { protected String doInBackground(Void... parameters) { List params = new ArrayList(); params.add(new BasicNameValuePair("user_id", user_id)); return api.post("", params); }//end doInBackground protected void onPostExecute(String result) { Log.i(TAG + "POST() => " + result); }//end onPostExecute }.execute(); //end AsyncTask } 

我看到了run-multiple-asynctasks的答案，但我不知道如何使用它。 如何在AsyncTask中实现以下代码：

  @TargetApi(Build.VERSION_CODES.HONEYCOMB) // API 11 void startMyTask(AsyncTask asyncTask) { if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) asyncTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, params); else asyncTask.execute(params); } 

Answer 1

从AsynTask创建调用并同步调用MainActivity中的类：

 public class ApiCalling extends AsyncTask() { protected String doInBackground(String... parameters) { Log.d("LogTag","starting Async Task:"+parameters[0]); List params = new ArrayList(); params.add(new BasicNameValuePair("user_id", user_id)); return api.post("", params); }//end doInBackground protected void onPostExecute(String result) { Log.i(TAG + "POST() => " + result); }//end onPostExecute }.execute(); //end AsyncTask 

从您的MainActivity onCreate（）：

 ApiCalling mObj = new ApiCalling(); mObj.execute("call 1"); /* if the task inside asyn task if long, then better to get new reference of Async task and execute other task */ ApiCalling mObj = new ApiCalling(); mObj.execute("call 2"); 

Answer 2

 import java.util.concurrent.BlockingQueue; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.ThreadFactory; import java.util.concurrent.ThreadPoolExecutor; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicInteger; import android.annotation.SuppressLint; import android.os.AsyncTask; import android.os.Build; /** * An executor for concurrently executing AsyncTask tasks * It takes all work for understanding device`s Android version * and executes your AsyncTasks tasks concurrently * @author Artem Zinnatullin ([e-mail]) * @version 1.2 */ public class AsyncTaskExecutor { private static final int CORE_POOL_SIZE; private static final int MAXIMUM_POOL_SIZE; private static final int KEEP_ALIVE; private static final TimeUnit TIME_UNIT; private static final BlockingQueue concurrentPoolWorkQueue; private static final ThreadFactory concurrentThreadFactory; private static final ThreadPoolExecutor concurrentExecutor; private AsyncTaskExecutor() {} static { CORE_POOL_SIZE = 5; MAXIMUM_POOL_SIZE = 128; KEEP_ALIVE = 1; TIME_UNIT = TimeUnit.SECONDS; concurrentPoolWorkQueue = new LinkedBlockingQueue(10); concurrentThreadFactory = new AsyncTaskThreadFactory(); concurrentExecutor = new ThreadPoolExecutor( CORE_POOL_SIZE, MAXIMUM_POOL_SIZE, KEEP_ALIVE, TIME_UNIT, concurrentPoolWorkQueue, concurrentThreadFactory ); } /** * Concurrently executes AsyncTask on any Android version * @param task to execute * @param params for task * @return executing AsyncTask */ @SuppressLint("NewApi") public static  AsyncTask executeConcurrently(AsyncTask task, Params... params) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { task.executeOnExecutor(concurrentExecutor, params); } else { task.execute(params); } return task; } /** * Thread factory for AsyncTaskExecutor * @author Artem Zinnatullin */ private static class AsyncTaskThreadFactory implements ThreadFactory { private final AtomicInteger count = new AtomicInteger(1);; @Override public Thread newThread(Runnable r) { return new Thread(r, "AsyncTask #" + count.getAndIncrement()); } } } 

如果要同时执行Asynctask，请使用此类。 找到这个课程，它为我工作。

 AsyncTaskExecutor.executeConcurrently(new YourAsyncTask(),1); 

的AsyncTask

 private class YourAsyncTask extends AsyncTask { @Override protected void onPreExecute() { super.onPreExecute(); Toast.makeText(mContext, "Please wait..Fetching Data", Toast.LENGTH_LONG).show(); } @Override protected String doInBackground(Integer... params) { Log.e("passing value",""+params[0]); String uri = "http://abcd.com/ServiceTest.php?id=" + params[0]; Log.e("passing value",""+uri); return SetServerString; } @Override protected void onPostExecute(String result) { super.onPostExecute(SetServerString); } 

希望它能帮到你！