Question

In my application, I am using onCreate(), for initialize of application, onStart() and onResume().

According to activity life cycle all of mentioned methods are running sequentially. In onStart() method, I have a custom dialog that when runs I take user id and password after that I send them to server and server sends me a token.

Then after taking Token I should go next step which is onResume().

but the problem is after showing dialog from onStart(), activity will go to next cycle, onResumme(). How can I say to android, “Hey guy, please don’t go to next cycle until I take token from server”?

This is my code:

@Override
    protected void onStart() {
        super.onStart();
        Log.i("MA_onStart", "Activity is abut to start...");

    .
    .
    .

        if(!isOnline())
        dialogWarning.show();


        if(!isTokenValid())
            dialog.show();
    }
}

In this code, I call isTokenValid(). If don’t have token then I will show a dialog to take user id and password. I want activity doesn’t go to next stage until I get token. I can add while loop to wrap

if(!isTokenValid()) dialog.show();

and set a flag for breaking the loop. I can set the flag when user click yes button in dialog but I afraid that if process takes some seconds, Android kill my process and application. what is your suggestion?

Thanks

==========>
Update

I changed the code to this

gotoNextCycle = true;
            while(gotoNextCycle)
            if(!isTokenValid())
                dialog.show();

and put gotoNextCycle = false; when user clicked yes button in dialog. As I expected, the application crashed.

Answer 1

What is the problem if you let Android continue with the cycle..
i mean what will happen if onResume() is called?

You should not wait in onStart() or onResume() for responses from server.
This would lead to ANR as you have observed.
You can update your app so that once you get response from server with valid token, you can refresh your view or data shown in the activity.
Maybe, let us know what information you are showing in the Activity, we can try to help you with a way to handle invalid Token case (fetch Token from server and update the information).

EDIT

you can refer the following code:

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

    if(isTokenValid()) {
       doProcess();
    } else {
       showDialog(USER_ID_DLG);
    }
  }

private void doProcess() {
   .... 
}

in onClick() of the dialog (yes button) start a Tread or AsyncTask to fetch Token from server. Meanwhile you can show a Progress dialog (“Loading… please wait” kinds).
Once you get response from server, in the Thread or AsyncTask dismiss this progress dialog and then call doProcess().

I assume you show some information in this activity to user based on the server response/Token. So once the Progress dialog is dismissed, your doProcess() can update the views.

If the authentication fails, then you can call finish() on the Activity after showing some Toast to user about the failure.

Also make sure you call setCancelable(false) on the Progress dialog.