我发现了一个我还没有在其他地方见过的解决方案。你可以使用一个自定义应用程序对象，它知道你是否有后台任务在进行，而不是试图在活动中做这件事，在方向改变时被销毁和重新创建。我在这里写过博客。

当你改变方向时，Android会终止那个活动并创建新的活动。 我建议使用Rx java的retrofit。自动处理崩溃。

在改造调用时使用这些方法。

.subscribeOn (Schedulers.io ()) .observeOn (AndroidSchedulers.mainThread ())

诀窍是在onPreExecute/onPostExecute期间像往常一样在AsyncTask中显示/解散对话框，尽管在方向改变的情况下，在活动中创建/显示一个对话框的新实例，并将其引用传递给任务。

public class MainActivity extends Activity {
    private Button mButton;
    private MyTask mTask = null;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        MyTask task = (MyTask) getLastNonConfigurationInstance();
        if(task != null){
            mTask = task;
            mTask.mContext = this;
            mTask.mDialog = ProgressDialog.show(this, "", "", true);        
        }

        mButton = (Button) findViewById(R.id.button1);
        mButton.setOnClickListener(new View.OnClickListener(){
            public void onClick(View v){
                mTask = new MyTask(MainActivity.this);
                mTask.execute();
            }
        });
    }


    @Override
    public Object onRetainNonConfigurationInstance() {
        String str = "null";
        if(mTask != null){
            str = mTask.toString();
            mTask.mDialog.dismiss();
        }
        Toast.makeText(this, str, Toast.LENGTH_SHORT).show();
        return mTask;
    }



    private class MyTask extends AsyncTask<Void, Void, Void>{
        private ProgressDialog mDialog;
        private MainActivity mContext;


        public MyTask(MainActivity context){
            super();
            mContext = context;
        }


        protected void onPreExecute() {
            mDialog = ProgressDialog.show(MainActivity.this, "", "", true);
        }

        protected void onPostExecute(Void result) {
            mContext.mTask = null;
            mDialog.dismiss();
        }


        @Override
        protected Void doInBackground(Void... params) {
            SystemClock.sleep(5000);
            return null;
        }       
    }
}

我什么都试过了。花了几天时间做实验。我不想阻止活动旋转。我的设想是:

向用户显示动态信息的进度对话框。例如:“连接到服务器…”，“下载数据…”，等等。 一个线程做繁重的工作，更新对话框 在最后用结果更新UI。

The problem was, when rotating the screen, every solution on the book failed. Even with the AsyncTask class, which is the correct Android way of dealing with this situations. When rotating the screen, the current Context that the starting thread is working with, is gone, and that messes up with the dialog that is showing. The problem was always the Dialog, no matter how many tricks I added to the code (passing new contexts to running threads, retaining thread states through rotations, etc...). The code complexity at the end was always huge and there was always something that could go wrong.

对我来说唯一有效的解决方案就是“活动/对话”技巧。这很简单，很天才，而且都是旋转证明:

Instead of creating a Dialog and ask to show it, create an Activity that has been set in the manifest with android:theme="@android:style/Theme.Dialog". So, it just looks like a dialog. Replace showDialog(DIALOG_ID) with startActivityForResult(yourActivityDialog, yourCode); Use onActivityResult in the calling Activity to get the results from the executing thread (even the errors) and update the UI. On your 'ActivityDialog', use threads or AsyncTask to execute long tasks and onRetainNonConfigurationInstance to save "dialog" state when rotating the screen.

这是快速和工作良好。我仍然使用对话框的其他任务和AsyncTask的一些东西，不需要一个固定的对话框在屏幕上。但在这种情况下，我总是使用活动/对话框模式。

而且，我没有尝试它，但它甚至可以阻止活动/对话框旋转，当线程运行时，加速事情，同时允许调用活动旋转。

我发现了一个更容易的解决方案来处理线程时，方向改变。你可以只保留一个静态引用到你的活动/片段，并在对ui进行操作之前验证它是否为空。我建议使用try catch:

 public class DashListFragment extends Fragment {
     private static DashListFragment ACTIVE_INSTANCE;

     @Override
     public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        ACTIVE_INSTANCE = this;

        new Handler().postDelayed(new Runnable() {
            public void run() {
                try {
                        if (ACTIVE_INSTANCE != null) {
                            setAdapter(); // this method do something on ui or use context
                        }
                }
                catch (Exception e) {}


            }
        }, 1500l);

    }

    @Override
    public void onDestroy() {
        super.onDestroy();

        ACTIVE_INSTANCE = null;
    }


}

我是一个新手在机器人，我尝试了这个，它是有效的。

public class loadTotalMemberByBranch extends AsyncTask<Void, Void,Void> {
        ProgressDialog progressDialog = new ProgressDialog(Login.this);
        int ranSucess=0;
        @Override
        protected void onPreExecute() {
            // TODO Auto-generated method stub
            super.onPreExecute();
            progressDialog.setTitle("");    
            progressDialog.isIndeterminate();
            progressDialog.setCancelable(false);
            progressDialog.show();
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_NOSENSOR);

        }
        @Override
        protected Void doInBackground(Void... params) {
            // TODO Auto-generated method stub

            return null;
        }
        @Override
        protected void onPostExecute(Void result) {
            // TODO Auto-generated method stub
            super.onPostExecute(result);
            progressDialog.dismiss();
            setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_NOSENSOR);
        }
}