Restart QApplication

[Svaths]

Hello all,

I am using Qt 3.3 Embedded Version.


1.) As part of our requirement, I intend to "RESTART" Qt alone leaving my application and data unerased.
Can it be done? Do I need to 'QApplication::exit(0)' and create a new 'QApplication myapplication' again?? Or is there a better way around??

2.) Currently Qt is opening Frame Buffer fb0 to write on to my LCD.
Is there a way by which I can switch between the FrameBuffers fb0 and fb2?
Atleast if there could be a way to disconnect and connect to the same frame buffer again from my application, it would be of great help to me....


Thanks in advance...





Regards,
Svaths

[wysota]

What exactly do you mean by a "restart"? You can try just exiting and reentering the event loop. I guess pending events will be processed then, but I don't know if that's what you want.

[Svaths]

Thanks Wysota, for the interest.

What exactly do you mean by a "restart"?

By "Restart", I Intend the QApplication to initiate startup like connecting to my framebuffer, keypad again.

The Problem:

When a certain event occurs, I need to stop writing into frame buffer fb0 and start writing to frame buffre fb2 and after a certain event, I need to revert it back

My Approach

(i) I planned to exit ( QApplication:;exit(0) ) , softlink fb0->fb2 and create a QApplication fresh so that it connects to fb0 again which is actually fb2. I could not easily do it...

After a proper exit , during recreation of QApplication,......... it said

#Semop lock failure Identifier removed
#Semop unlock failure Identifier removed

and it hung

(ii) If I can switch between the frame buffers fb0 anf fb2 when required, the problem could be solved.... But I dont know if it is possible

Hence the reason, I was looking for a way out to RESTART QApplication without having to exit and create a new one...

Hope I am a bit clear now.........




Thanks in advance.....

Regards,
Svaths

[wysota]

I don't think you can create a second application object. Maybe it'd be easier to save the state somewhere, restart the application completely and restore the state?

[Svaths]

Thanks for the Info, Wysota.

Maybe it'd be easier to save the state somewhere, restart the application completely and restore the state?

You meant the Session Manager, I Suppose. I shall surely try this. Thanks.

Regarding the Frame Buffers, Can I assume that there is no safe way to switch between frame buffers dynamically??


Thanks in advance,
Regards,
Svaths

[wysota]

You meant the Session Manager, I Suppose. I shall surely try this. Thanks.

I meant any mechanism. You can use the session manager but you can also just dump the state to some file.

Regarding the Frame Buffers, Can I assume that there is no safe way to switch between frame buffers dynamically??

I don't know much about embedded systems, so I can't confirm that, but it's highly unprobable that such a method exists. You can't reconnect to a different X server on the fly, so probably you also can't reconnect to a different framebuffer on the fly.