BlackBerry: "Application is not responding; process terminated" because of UiApplication.getUiApplication().popScreen()?

Question

I have a Blackberry application which, when run in some emulators with touch support (ex: 9500, 9520, 9530, 9550), terminates with:

"Application is not responding; process XPTO terminated"

Using logs, I found out that it seems like the application is stopping in a class where I asynchronously make HTTP requests: something like:

public class LoadingFullScreen extends FullScreen implements Runnable {

    private Thread actionThread = null;

    protected void onDisplay() {
        actionThread = new Thread(this);
        actionThread.start();
    }

    protected void onUndisplay() {
        if(actionThread != null && actionThread.isAlive()) {
            actionThread.interrupt();
        }
    }

    public void run() {
        //make http requests - this is done successfully

        synchronized(Application.getEventLock()) {
                Screen active = UiApplication.getUiApplication().getActiveScreen();
                if (active instanceof LoadingFullScreen) {
                    Logger.debug("LoadingFullScreen popping screen"); //this appears in logs
                    UiApplication.getUiApplication().popScreen(active);
                    Logger.debug("LoadingFullScreen screen popped"); //this never appears in logs
                }
        }
    }
}

I launch this screen with UiApplication.getUiApplication().pushModalScreen(new LoadingFullScreen())

In the logs I can see:

[0.0] Wed Jul 27 17:53:06 GMT 2011 - DEBUG: LoadingFullScreen popping screen
[0.0] JVM: bklt[1] @163148: JBSC on=0
[0.0] JVM: bklt[1] @163148: SC 0
[0.0] JVM: bklt[1]: setTimeout 30
[0.0] Application XPTO(212) is not responding; process terminated

It seems like UiApplication.getUiApplication().popScreen() is blocking the application, and so the OS kills the application, but why?

EDIT:
I have also tried using

UiApplication.getUiApplication().invokeLater(new Runnable() {...} };            

instead of synchronized(Application.getEventLock()) {...} but I have the exact same result

EDIT 2:
I have also tried active.close() instead of UiApplication.getUiApplication().popScreen(active); but I have the exact same result

EDIT 3: Using javaloader I got this kind of stacktrace from the emulator:

guid:0x9C3CD62E3320B498 time: Thu Jul 28 15:02:50 2011  severity:0 type:3 app:Java Exception data:
    ForcedStackTraceException
    net_rim_services_impl(4) 27 2 0x1030B000
    net_rim_os-3(4BEF0320)
     HttpConnectionManager$CleanupThread
     run
     0x3B09
guid:0x9C3CD62E3320B498 time: Thu Jul 28 15:02:50 2011  severity:0 type:3 app:Java Exception data:
    ForcedStackTraceException
    XPTO(247) 60 4 0x124A0400
    net_rim_cldc-16(4BEEF8A5)
     TextField
     getFocusRect
     0x2A61
    net_rim_cldc-12(4BEEF8A5)
     Manager
     getFocusRect
     0x717
    net_rim_cldc-12(4BEEF8A5)
     Manager
     getFocusRect
     0x717
    net_rim_cldc-12(4BEEF8A5)
     Screen
     getFocusRect
     0x9AF2
    net_rim_cldc-12(4BEEF8A5)
     Screen
     callOnExposed
     0x9D16
    net_rim_cldc-13(4BEEF8A5)
     UiEngineImpl
     <private>
     0x9007
    net_rim_cldc-13(4BEEF8A5)
     UiEngineImpl
     removeScreen
     0x7D08
    net_rim_cldc-12(4BEEF8A5)
     Screen
     close
     0x6B66
    XPTO-8(4E316B06)
     LoadingFullScreen$1
     run
     0x34D5
    net_rim_cldc-8(4BEEF8A5)
     Application
     dispatchInvokeLater
     0x1A87
    net_rim_cldc-8(4BEEF8A5)
     Application
     <private>
     0x2809
    net_rim_cldc-8(4BEEF8A5)
     Application
     processNextMessage
     0x1AEF
    net_rim_cldc-9(4BEEF8A5)
     ModalEventThread
     run
     0xBE4F
guid:0x9C3CD62E3320B498 time: Thu Jul 28 15:02:50 2011  severity:0 type:3 app:Java Exception data:
    ForcedStackTraceException
    XPTO(247) 30 2 0x139DA800
    net_rim_cldc(4BEEF8A5)
     Object
     wait
     0x9922
    net_rim_cldc-8(4BEEF8A5)
     Application
     startModalEventThread
     0x1EB8
    net_rim_cldc-13(4BEEF8A5)
     UiEngineImpl
     addScreenModal
     0x83F4
    net_rim_cldc-13(4BEEF8A5)
     UiEngineImpl
     pushModalScreen
     0x674E
    net_rim_cldc-13(4BEEF8A5)
     UiApplication
     pushModalScreen
     0x62B0
    XPTO-8(4E316B06)
     MyBaseScreen
     <private>
     0x3AA6
    XPTO-8(4E316B06)
     MyBaseScreen
     openTheModalScreenFunction
     0x382C
    XPTO-8(4E316B06)
     MyBaseScreen$4
     fieldChanged
     0x4271
    net_rim_cldc-11(4BEEF8A5)
     Field
     fieldChangeNotify
     0x160B
    net_rim_cldc-16(4BEEF8A5)
     TextField
     replace
     0x7A5
    net_rim_cldc-16(4BEEF8A5)
     TextField
     inputMethodTextChanged
     0x24E1
    net_rim_cldc-15(4BEEF8A5)
     PasswordEditField
     inputMethodTextChanged
     0x4F26
    net_rim_cldc-27(4BEEF8A5)
     IMContext
     dispatchInputMethodEvent
     0x1E00
    net_rim_tid-4(4BEEF8E1)
     SLInputMethod
     sendComposedText
     0x5CA1
    net_rim_tid-4(4BEEF8E1)
     SLInputMethod
     sendComposedText
     0x5BD1
    net_rim_tid_fastEuropean(4BEF034C)
     FastEuropeanInputMethod
     sendComposedText
     0x48E1
    net_rim_tid_fastEuropean(4BEF034C)
     FastEuropeanInputMethod
     dispatchConversionEvent
     0x43E3
    net_rim_tid-4(4BEEF8E1)
     SLInputMethod
     dispatchKeyEvent
     0x5309
    net_rim_tid-4(4BEEF8E1)
     SLInputMethod
     dispatchEvent
     0x63CA
    net_rim_tid_fastEuropean(4BEF034C)
     FastEuropeanInputMethod
     dispatchEvent
     0x426E
    net_rim_cldc-27(4BEEF8A5)
     InputContext
     dispatchEvent
     0x3E15
    net_rim_cldc-27(4BEEF8A5)
     IMContext
     dispatchEvent
     0x21DE
    net_rim_cldc-11(4BEEF8A5)
     Field
     dispatchEvent
     0x3739
    net_rim_cldc-16(4BEEF8A5)
     TextField
     dispatchEvent
     0x30F6
    net_rim_cldc-27(4BEEF8A5)
     EventHandler
     <private>
     0x1460
    net_rim_cldc-27(4BEEF8A5)
     EventHandler
     processKeyEvent
     0x1A79
    net_rim_cldc-16(4BEEF8A5)
     TextField
     processKeyEvent
     0x37F6
    net_r

EDIT 4: I have tried to move the run() method in LoadingFullScreen to a new Runnable class, as I was told that having LoadingFullScreen implement Runnable could cause problems when that class is shown as a modal screen.
However, I had no luck and I still have the same problem.
Any ideas?

EDIT 5: Solved here: BlackBerry: "Application is not responding; process terminated" because of UiApplication.getUiApplication().popScreen()?

Answer 1

As none of the answers solve the problem, I am posting here the solution I reached with help from other forum (http://supportforums.blackberry.com/t5/Java-Development/Application-is-not-responding-process-terminated-because-of/m-p/1234573#M168285)

I didn't find it relevant, but it seems that the way I was calling LoadingFullScreen matters:

public void fieldChanged(Field field, int context) {
    LoadingFullScreen loading  = new LoadingFullScreen();
    System.out.println("calling pushModalScreen"); //this was showing up in logs
    UiApplication.getUiApplication().pushModalScreen(loading);
    System.out.println("pushModalScreen done"); //this wasn't showing up in logs    
}

It turns out the emulators/devices I mentioned have support for 'SureType'. "That means they do some off things when you press a key. Typically, they will attempt to display a 'choice' for the user, becuase each key has two options. becuase you are doing a pushModal in the FieldChanged method, you are blocking this. And this I think is what it is getting upset about."

So the solution was to change the way this instead:

public void fieldChanged(Field field, int context) {
    if ( context != FieldChangeListener.PROGRAMMATIC ) {
        UiApplication.getUiApplication().invokeLater(new Runnable() { 
            public void run() {
                LoadingFullScreen loading  = new LoadingFullScreen();
                UiApplication.getUiApplication().pushModalScreen(loading);          
            }
        }
    }
}