[vcoleman]

I have an application loaded at startup that inserts a menuitem when messages are listed. When the menu item is selected it's supposed to display a screen derived from MainScreen, but nothing happens. I searched the forum for menuitem issues and source for bbcorrector was mentioned but I am unable to find the java; just binaries. If I load "MyScreen" from the constructor of an application that extends UiApplication it works. What is going on? Any thoughts? Any other way to do this? Once again my ultimate goal is to load a menuitem on startup and on selection takeover the screen. Thanks... The relevant code looks like this:

public final class TheApp extends UiApplication {
public static void main(String[] args) {
new TheApp().enterEventDispatcher();
}

public TheApp() {
super();
ApplicationMenuItemRepository amir =
ApplicationMenuItemRepository.getInstance();
amir.addMenuItem (ApplicationMenuItemRepository.MENUITEM_MESSAGE_LI ST,
new MyMenuItem());
}


private class MyScreen extends MainScreen {
//variables for the user interface
LabelField _title;

public MyScreen() {
super();//invoke MainScreen constructor
//define title of the app
_title = new LabelField("My Screen", LabelField.ELLIPSIS
| LabelField.USE_ALL_WIDTH);
setTitle(_title);
}

private class MyMenuItem extends ApplicationMenuItem {
MyMenuItem() {
super(20);
}

public String toString() {
return "Open My Screen";
}

public Object run(Object context) {
invokeLater(new Runnable()
{
public void run()
{
pushScreen(new MyScreen());
}
});

return null;
}
}

[vcoleman]

After much frustration/experimentation it seems that the problem is that


pushScreen(...); // nothing happens

is not the same as

UiApplication.getUiApplication().pushScreen(...); // IT WORKS !

I used invokeLater(...) because the JDE reported : @2D480000 "UI engine accessed without holding the event lock.".

But it is not necessary to use invokeLater(...) so long as it's
UiApplication.getUiApplication().invokeLater(...)

It seems that the compile time UiApplication is not the same as the current runtime application.

In any case, a suggested cautious practice would be to explicity name your application objects in your code like this:

application.invokeLater(...);
application.pushScreen(...);

OR

UiApplication.getUiApplication().whatever(...)

unless you are quite sure

UiApplication.this == UiApplication.getUiApplication() such as during the app's construction...


Can anyone confirm or add to this explanation?

[DoomBringer]

You're confusing the two UiApplications here. You're extending UiApplication, so you get your own pushScreen function, which is fine. However, invoking that has nothing to do with the screen that is currently being displayed. Thus, to open your screen, you need to get the current UiApp, and push the screen onto the screen stack.
You're running into this issue because you're a menu entry. If you were a normal app, you could call your own pushScreen function, because then you would be the current UiApp being shown to the user.
Did that make sense?