Air3.0 and the softKeyboard not appearing on Stage.focus = InputTextfield on iOS

I think we're experiencing an issue with this:

We're trying to use the iCade cabinet with an iPad and a Flash application (though this shouldn't affect the problem as the problem can be replicated without any connection or involvement with the iCade unit).

To make sure that the app is able to respond to the iCade's input (which is a simulation and transmission of certain keystrokes for each input), we create a TextField set off-screen and keep it visible (as this seems to be a requirement), and then we set the stage focus to that TextField. We also invoke requestSoftKeyboard on the TextField.

I learnt from this thread that setting stage focus isn't required, but I had the same issue as someone else here, in that I read that requestSoftKeyboard isn't supported on iOS - the documentation could be more clear about exactly what this means, like it's been explained here. Besides, setting stage focus should be fine, and not the cause of the issue I'm about to explain.

We have needsSoftKeyboard=false on the TextField, and after setting that, we request the soft keyboard. The upside is that this appears to prime the runtime to respond to keyboard input regardless of where it's coming from, and the keyboard usually stays hidden. Our problem is that, sometimes on app startup and sometimes up to 15 minutes of idle time later, the soft keyboard appears without prompt or user input.

Is this intended behaviour? We're only developing this application for iOS, and aren't sure if the issue is perhaps to do with the iOS soft keyboard.

We also tried handling the soft keyboard events (such as Activate, Activating and Deactivate) to attempt to stopImmediatePropagation and preventDefault. These seem to conflict with our setting focus in the first place, so I don't think we can make use of these. We tried only preventing the event when our target TextField already has focus, but this didn't work, and I think at this point we were really just shooting in the dark!

I use the following codes on iOS and it works fine.

public function Main() {

   ...

   txt.type = TextFieldType.INPUT;

   txt.needsSoftKeyboard = true;

   txt.addEventListener(FocusEvent.FOCUS_IN, onTxtFocusIn);

   ...          

}

private function onTxtFocusIn(event:FocusEvent):void {

   ...

   txt.requestSoftKeyboard();

   ...

}