0

我的应用需要从服务器获取数据。因此，我在方法中显示ProgressDialogonPreExecute() ，并在该doInBackground()方法中从服务器加载数据。

此时如果我改变方向，应用程序强制关闭。因为当前活动已被销毁，并且doInBackground()可能仍会引用旧活动。所以，我参考了这篇讨论同样问题的帖子。但我不想使用android:configchanges，因为它不是首选。androiddevelopersite说这应该是最后的手段，而不是大多数应用程序的首选。

那么，有人可以就如何以我的应用程序不会强制关闭的方式处理这种情况提出必要的代码片段吗？

Eidt：我的代码

    public class DataListActivity extends BaseActivity {

        private ArrayList<String> valueslist;

        public void onCreate(Bundle savedInstanceState)
        {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.listlayout);
                     new LoadAsync().execute();

        }


         class LoadAsync extends AsyncTask<String, String, String> {

                /**
                 * Before starting background thread Show Progress Dialog
                 * */
                @Override
                protected void onPreExecute() {
                    super.onPreExecute();
                    progressDialog = new ProgressDialog(DataListActivity.this);
                    progressDialog.setMessage("Loading...");
                    progressDialog.setIndeterminate(false);
                    progressDialog.setCancelable(false);
                    progressDialog.show();
                }

                /**
                 * getting All datafrom url
                 * */
                protected String doInBackground(String... args) {

                    //Here I am doing httppost request.
                           try{ 
                            // looping through All data that I got from the server
                            for (int i = 0; i < subCategoriesJson.length(); i++) {
                                JSONObject jsonobj = subCategoriesJson.getJSONObject(i);

                                // Storing each json item in variable
                                String item = jsonobj.getString("data");

                                valueslist.add(item);

                            }
                            return "1";
                        }                    
                        else {

                            return null;
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }   
                    return null;
                }

   protected void onPostExecute(String msg) {

                    if( msg != null && msg.equals("1"))
                    {

                     progressDialog.dismiss();

                     runOnUiThread(new Runnable() {

                         public void run() {
                             //Updating parsed json data to Listview

                            ListView listView = (ListView)findViewById(R.id.list1);

            ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getApplicationContext(),R.layout.list_item, valueslist);
                                listView.setAdapter(arrayAdapter); 

          listView.setOnItemClickListener(new OnItemClickListener() {

            @Override
                            public void onItemClick(AdapterView<?> parent, View view,
                                            int position, long id) {


                                 String selectedthing = valueslist.get(position);

                                    }
                                }); 

                         }
                     });
                }else 
                {
                          //There is no data.
                }

                }

         }

    }

注意：我正在提供此信息，尽管此问题不是必需的。我的活动有两个布局文件。一个用于纵向，另一个用于文件夹中的横向模式。layout-land

下面是 logcat 窗口：

02-27 19:54:40.294: E/WindowManager(11710): Activity com.example.DataList has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@40555388 that was originally added here
02-27 19:54:40.294: E/WindowManager(11710): android.view.WindowLeaked: Activity com.example.prog.DataList has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@40555388 that was originally added here
02-27 19:54:40.294: E/WindowManager(11710):     at android.view.ViewRoot.<init>(ViewRoot.java:277)
02-27 19:54:40.294: E/WindowManager(11710):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:148)
02-27 19:54:40.294: E/WindowManager(11710):     at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
02-27 19:54:40.294: E/WindowManager(11710):     at android.view.Window$LocalWindowManager.addView(Window.java:433)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.Dialog.show(Dialog.java:265)
02-27 19:54:40.294: E/WindowManager(11710):     at com.example.prog.DataList$LoadAsync.onPreExecute(DataList.java:77)
02-27 19:54:40.294: E/WindowManager(11710):     at android.os.AsyncTask.execute(AsyncTask.java:391)
02-27 19:54:40.294: E/WindowManager(11710):     at com.example.prog.DataList.onCreate(DataList.java:52)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1072)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1794)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1851)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.ActivityThread.access$1500(ActivityThread.java:132)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1038)
02-27 19:54:40.294: E/WindowManager(11710):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-27 19:54:40.294: E/WindowManager(11710):     at android.os.Looper.loop(Looper.java:150)
02-27 19:54:40.294: E/WindowManager(11710):     at android.app.ActivityThread.main(ActivityThread.java:4277)
02-27 19:54:40.294: E/WindowManager(11710):     at java.lang.reflect.Method.invokeNative(Native Method)
02-27 19:54:40.294: E/WindowManager(11710):     at java.lang.reflect.Method.invoke(Method.java:507)
02-27 19:54:40.294: E/WindowManager(11710):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
02-27 19:54:40.294: E/WindowManager(11710):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
02-27 19:54:40.294: E/WindowManager(11710):     at dalvik.system.NativeStart.main(Native Method)
02-27 19:54:40.294: E/ResourceType(11710): Style contains key with bad entry: 0x010102f3
02-27 19:54:40.294: E/ResourceType(11710): Style contains key with bad entry: 0x01010300
02-27 19:54:40.294: E/ResourceType(11710): Style contains key with bad entry: 0x0101039c
4

3 回答 3

2

您必须在 中关闭您的对话框onPause()，如果需要，在 中再次显示它onResume()。

您可能希望保留有关 Activity 实例之间的对话的一些状态，onRetainNonConfigurationInstance()并从传递给 的 Bundle 中检索它onCreate()。

于 2013-02-27T14:11:32.743 回答
1

您可以在等待来自服务器的数据时禁用方向更改。您可以暂时设置您的方向肖像：

setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);

有关更多、清晰的解释，请访问：如何在 Android 上禁用方向更改？

于 2013-02-27T12:54:07.757 回答
0

这与西蒙给你的答案相同，但有一个代码示例。必须检查进度是否完成，否则进度条会显示卡在 100%。

@Override
public void onPause() {
    super.onPause();  // Always call the superclass method first

    proDialog.dismiss();
}

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


    proDialog.show();
}
于 2014-10-10T09:16:25.977 回答