Java Development

[jeyaprakash]

My application return this exception when i call My previous Mainscreen

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

                        public void run() {
                            UiApplication.getUiApplication().pushScreen(firstscreen);

                        }
                    }); 

????????

[marchywka]

I'm not really sure what you are asking. You normally push the screen before starting the app.

I have something called Phlauncher that starts like the code below. invokelater is for running

"stuff" that happens while the app is running. For example, I have stuff like this line,   invokeLater(new NavigateTo(url,this)); 

public static void main(String[] args) {
    Phlauncher app= new Phlauncher(new DefPhluParam() );
        app.enterEventDispatcher();
    }
    public Phlauncher(PhluParam pp )
    {          
            _mainScreen = new PhluScreen(this);
        _mainScreen.add(new BitmapField(_oBitmap)); 
       // rtc=new RichTextField("loading");
               pushScreen(_mainScreen);

Message Edited by marchywka on 09-19-2008 09:13 AM

[jeyaprakash]

hi marchywk

am calling a screen that was pused already it was in background for example my firstscreen is in background i do some stuf with my second screen after tat i calling my first screen object using

        pushscrren(firstscreen);

method i got Uncaut exception attempt to push screen while already displayed wats my problem...

by..

jp

[marchywka]

AFAIK you can push multiple screens but apparently it doesn't like the same screen pushed twice.

I've never had this problem as I just use one screen and modify the layout. I've actually

got my own stack of rendered fields and just change the screen layout,

Run something like this in invokelater,

_mainScreen.deleteAll();
   _mainScreen.add(field);   

[peter_strange]

jeyaprakash.  How do you get from your first to your second screen? 

If you do the standard BlackBerry thing, you will, from something like a menu handler in the first screen, use a push to go to the second screen.  Assuming you do that, then both your screens are on the 'stack', just the second one is on top of the first one.  So all you have to do is pop the second screen, and your first one will appear.

Does that help?

If not, can you clarify how you get to your second screen, and what you mean when you say your first screen is in background.

[simon_hain]

if you push a screen it is pushed on the stack, on top of all screens that are already there. only the topmost screen is displayed.
if you want to display the previous screen you have to pop the current one, using popScreen(getActiveScreen()) or something similar.

or you can use a single screen to display, has some merits and some backdraws.

[jeyaprakash]

Thanku all

             my problem solved i delete my activescreen using popscreen( currentscreen) before switching ..