How Do I Minimize a J2ME App?

Question

I need my J2ME app to run in the background and still allow the user to use his mobile without problem. the app still needs to process some events in the background.

I would also like to allow the user to stop the app if he wants to.

How can I accomplish this?

Answer 1

Running a midlet in the background but still processing is not specified in the j2me standard i think. Normaly at the moment your midlet is moved to background the paused method should be called.

But not every vendor implements it that way. Symbian keeps your program running as if there was no change when minimized. At least on the N80 and N90.

Answer 2

A device's ability to run an application in the background depends on its ability to multitask. Therefore, more expensive, PDA-type devices are more likely to support background execution than lower-cost devices. For in background :-

 private Display display = Display.getDisplay(this);
 private Displayable previousDisplayable;

 public void toBack() {
 previousDisplayable = display.getCurrent();
 display.setCurrent(null);
 }

And foreground :-

public void toFront() {
display.setCurrent(previousDisplayable);
}

But Be aware that every device not supports that features.(Works on Nokia s60, SonyEricsson, but not on Nokia s40, Samsung and some others).