android - 进度对话框坏 token 异常

Question

我已经阅读这些帖子很长时间了，但我还没有看到任何描述我遇到的问题的内容。当我在安装后第一次打开我的应用程序时，一切正常，但是当我点击后退按钮退出应用程序然后再次打开它时，它失败并显示“不幸的是，我的应用程序已停止。”对话框弹出。我点击确定，然后一旦我再次打开应用程序，它就可以工作了……我有一个简单的回调函数，我在其中传递 fragment 管理器。一旦我的异步任务完成，它就会调用回调并启动 fragment 。完整代码如下

updateList(MainActivity.this, getSupportFragmentManager())
.
.
.


public void updateList(Activity activity, FragmentManager fragmentMgr)
{
 MyCallback callback = new MyCallback(fragmentMgr); 
 MyAsyncTask myTask = new MyAsyncTask(activity, callback);
          myTask.execute();

}
private class MyAsyncTask extends AsyncTask<String, Void, String>
{
   private ProgressDialog progressDialog;
   private MyCallback callback;

        MyAsyncTask(Activity activity, MyCallback callback) {

        // Init the progress dialog
    this.callback = callback;
    progressDialog = new ProgressDialog(activity);
    progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);       

    }

    protected void onPreExecute() {
        this.progressDialog.setMessage("Loading...");
        this.progressDialog.show();

    }

@Override
    protected String doInBackground(String... input) {
 // Update list...

}

protected void onPostExecute(String result) {

        progressDialog.dismiss();
        callback.run(result);

}
}

public class MyCallback{

private FragmentManager fragmentManager;    

public UpdateListCallback(FragmentManager fragmentManager)
{
    this.fragmentManager = fragmentManager;     
}

@Override
public void run(String result) {

    // update fragment with results...


    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
    fragmentTransaction.replace(R.id.fragmentContent, new ListFragment());
    fragmentTransaction.addToBackStack(null);

    fragmentTransaction.commitAllowingStateLoss();
}

 }

我传入 AsyncTask 的 Activity 是 FragmentActivity。

这非常有效，直到我退出应用程序，通过后退按钮直到我到达我的主屏幕。当我再次打开我的应用程序时，它会尝试加载 progressDialog 但它失败了

07-09 15:42:53.030: E/AndroidRuntime(26915): FATAL EXCEPTION: main
07-09 15:42:53.030: E/AndroidRuntime(26915): java.lang.RuntimeException: Unable to start activity ComponentInfo{myapp/myapp.MainActivity}: android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@41d54798 is not valid; is your activity running?
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2100)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.ActivityThread.access$600(ActivityThread.java:140)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.os.Handler.dispatchMessage(Handler.java:99)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.os.Looper.loop(Looper.java:137)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.ActivityThread.main(ActivityThread.java:4898)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at java.lang.reflect.Method.invokeNative(Native Method)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at java.lang.reflect.Method.invoke(Method.java:511)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at dalvik.system.NativeStart.main(Native Method)
07-09 15:42:53.030: E/AndroidRuntime(26915): Caused by: android.view.WindowManager$BadTokenException: Unable to add window -- token android.os.BinderProxy@41d54798 is not valid; is your activity running?
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.view.ViewRootImpl.setView(ViewRootImpl.java:706)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:345)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.view.Window$LocalWindowManager.addView(Window.java:554)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.Dialog.show(Dialog.java:277)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at myapp.MyList$MyAsyncTask.onPreExecute(MyList.java:313)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.os.AsyncTask.execute(AsyncTask.java:534)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at myapp.MyList.updateMyList(DeviceList.java:279)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at myapp.DbAdapter.PopulateMyList(DbAdapter.java:323)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at myapp.MainActivity.onCreate(MainActivity.java:42)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.Activity.performCreate(Activity.java:5206)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083)
07-09 15:42:53.030: E/AndroidRuntime(26915):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064)

Answer 1

不要在Async Task中创建ProgressDialog progressDialog，在Activity中创建并作为参数传递给Async Task