android - 致命异常 : AsyncTask

Question

今天我在执行 AsyncTask 时遇到了 android 应用程序中的问题。异常日志是 -

   FATAL EXCEPTION: AsyncTask #1
   java.lang.RuntimeException: An error occured while executing doInBackground()
   at android.os.AsyncTask$3.done(AsyncTask.java:299)
   at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
   at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
   at java.util.concurrent.FutureTask.run(FutureTask.java:239)
   at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
   at java.lang.Thread.run(Thread.java:838)
   Caused by: java.lang.ClassCastException: java.lang.Object[] cannot be cast to          java.lang.Void[]
   at com.android.demo.DashBoardActivity$3.doInBackground(DashBoardActivity.java:1)
   at android.os.AsyncTask$2.call(AsyncTask.java:287)
   at java.util.concurrent.FutureTask.run(FutureTask.java:234)

我不明白错误是什么以及应用强制关闭的原因。 这种情况不会发生在第一次运行后，而是第二次运行应用程序会导致异常。

提前致谢。

已编辑-

我在 DashBoardActivity 中使用以下方法注册到 GCM-

public void registerToGCM(){
    try{
          GCMRegistrar.checkDevice(this);
          GCMRegistrar.checkManifest(this);
          registerReceiver(mHandleMessageReceiver, new IntentFilter(
                    AppConstents.DISPLAY_MESSAGE_ACTION));

            final String regId = GCMRegistrar.getRegistrationId(this);
            if (regId.equals("")) {
                GCMRegistrar.register(this, AppConstents.SENDER_ID);
            } else {
                if (GCMRegistrar.isRegisteredOnServer(this)) {
                    Toast.makeText(getApplicationContext(), "Already registered with GCM", Toast.LENGTH_LONG).show();
                } else {
                    final Context context = this;
                    final AsyncTask mRegisterTask = new AsyncTask<Void, Void, Void>() {

                        @Override
                        protected Void doInBackground(Void... params) {
                            GCMServerUtilities.register(context,regId);
                            return null;
                        }

                        @Override
                        protected void onPostExecute(Void result) {
                          //  mRegisterTask = null;
                        }

                    };
                    mRegisterTask.execute(null, null, null);
                }
            }
    }
    catch(Exception e){
        e.printStackTrace();
    }
}

Answer 1

可以通过三种方式解决:

1:

final AsyncTask mRegisterTask = new AsyncTask<Object, Void, Void>() {.....

protected Void doInBackground(Object... params) {...

mRegisterTask.execute();

2:

final AsyncTask<Void, Void, Void> mRegisterTask = new AsyncTask<Void, Void, Void>() {.....

mRegisterTask.execute();

3:

final AsyncTask mRegisterTask = new AsyncTask<Void, Void, Void>() {.....

Void[] param = null;

mRegisterTask.execute(param);