使用AsyncTask进行AlertDialog

Question

任何人都知道如何将AlertDialog放入AsyncTask？我有使用WebService的应用程序。所以我已经把IP地址，以启动应用程序。目前我必须把默认的IP地址，然后我改变它使用AlertDialog，所以喜欢设置 - >插入IP。现在我想每次应用程序启动时，首先创建AlertDialog。我认为对于该解决方案，我必须使用AsyncTask。但是在我执行的方式，我有使用AsyncTask

下图显示的时候没有的AsyncTask应用FORR IP

@Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     // set the ip address 
     ip = "124.23.204.135"; 

     //asyncTask for updating gamer's information 
     new GamerWorker().execute(ip); 

     //refreshing GUI 
     intent = new Intent(this, BroadcastService.class); 

我使用AsyncTaskGamerWorker()以更新从WebService的信息对于一些问题。我还声明了刷新GUI的意图。下图显示，当我实现AsyncTask为AlertDialog

@Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     // set the ip address 
     LayoutInflater inflater = getLayoutInflater(); 
     final View dialoglayout = inflater.inflate(
       R.layout.alertdialog_add_gamer, null); 
     // start creating the dialog message 
     Builder builder = new AlertDialog.Builder(this); 
     builder.setView(dialoglayout); 
     builder.setPositiveButton("Yes", 
       new DialogInterface.OnClickListener() { 
        @Override 
        public void onClick(DialogInterface dialog, int id) { 
         // get the editText from the dialog's view 
         EditText text = (EditText) dialoglayout 
           .findViewById(R.id.et_gamerIpOrWebAdress); 
         // disable all input views 
         ip = text.getText().toString(); 

        } 
       }); 
     builder.setNegativeButton("No", 
       new DialogInterface.OnClickListener() { 
        @Override 
        public void onClick(DialogInterface dialog, int id) { 
         // cancels the dialog 
         dialog.dismiss(); 
        } 
       }); 
     new MyTask(builder).execute(); 
     //refreshing GUI 
     intent = new Intent(this, BroadcastService.class); 
    } 

而对于AsyncTask，我是用我宣布：

public class MyTask extends AsyncTask<Void, Void, Void> { 
      private Builder builder; 

     public MyTask(Builder builder) { 
      this.builder = builder; 
      } 

      public void onPreExecute() { 
      AlertDialog dialog = builder.create(); 
      dialog.show(); 
      } 

      public Void doInBackground(Void... unused) { 
      return null; 
      } 

      public void onPostExecute(Void unUsed) { 
      new GamerWorker().execute(ip); 
      } 
     } 

其实从AlertDialog，我下面这样的回答：How to display progress dialog before starting an activity in Android? 我的问题是，当我把：

  //refreshing GUI 
     intent = new Intent(this, BroadcastService.class); 

在preExecute不工作，但如果我把onC reate，它会得到空指针。任何人都知道如何解决这个问题，使启动应用程序

编辑时，我可以用AlertDialog：我可以把意图在preExecute，只是改变意图intent = new Intent(MainActivity.this, BroadcastService.class);。但似乎无法解决问题。该对话框从未被创建过，并且总是得到空指针。任何人都知道？

Answer 1

现在我解决不使用AsyncTask。所以我刚刚宣布onCreate()，然后If -statement如果IP为空则显示对话框。如果用户放置IP的情况，它会执行AsyncTask以更新信息到WebService，正如我前面提到的那样。

 ip = ""; 
     // start creating the dialog message 
     builder = new AlertDialog.Builder(this); 
     builder.setView(dialoglayout); 
     builder.setPositiveButton("Yes", 
       new DialogInterface.OnClickListener() { 
        @Override 
        public void onClick(DialogInterface dialog, int id) { 
         // get the editText from the dialog's view 
         EditText text = (EditText) dialoglayout 
           .findViewById(R.id.et_gamerIpOrWebAdress); 
         // disable all input views 
         ip = text.getText().toString(); 
         if (!ip.equals("")) 
         { 
          new GamerWorker().execute(ip); 

          //refreshing GUI 
          intent = new Intent(MainActivity.this, BroadcastService.class); 
         } 
         //clear(); 
         //myList.clear(); 

        } 
       }); 
     builder.setNegativeButton("No", 
       new DialogInterface.OnClickListener() { 
        @Override 
        public void onClick(DialogInterface dialog, int id) { 
         // cancels the dialog 
         dialog.dismiss(); 
        } 
       }); 

     if (ip.equals("") && ip.isEmpty()) 
     { 
      AlertDialog dialog = builder.create(); 
      dialog.show(); 

     } 
     else 
     { 
     // set the ip address 
      //ip = "123.123.224.133"; 
      new GamerWorker().execute(ip); 
      intent = new Intent(MainActivity.this, BroadcastService.class); 
     } 
    } 

如果有人使用另一种解决方案AsyncTask，请让我知道。谢谢