<![CDATA[Creating wait screen]]>Hello group,

I was trying to create a screen(widget) which would display some wait symbol, while there is some background work is going on.
Can i display a new widget on a different(new) thread? I don't have much idea about multithread programming. So if you guys can suggest me some resources, it will be very helpful to me :)

Thanks & Regards,
Durgesh K

]]>https://forum.qt.io/topic/8314/creating-wait-screenRSS for NodeWed, 17 Jun 2026 03:07:57 GMTFri, 05 Aug 2011 18:42:10 GMT60<![CDATA[Reply to Creating wait screen on Sat, 13 Aug 2011 15:00:33 GMT]]>Unfortunately, a QProgressBar would suffer from the same shortcomings as a QProgressDialog if the main event loop is blocked by the work in progress. DurgeshK mentioned that his processing is running 3rd-party code, so there's no way to process events during the work being done.

]]>https://forum.qt.io/post/105048https://forum.qt.io/post/105048Sat, 13 Aug 2011 15:00:33 GMT<![CDATA[Reply to Creating wait screen on Sat, 13 Aug 2011 09:24:04 GMT]]>You can always try to use "QProgressBar":http://doc.qt.nokia.com/latest/qprogressbar.html, set its minimum and maximum to 0 and its value to -1. And you get busy indicator without any progress only indicating that something is loading.

]]>https://forum.qt.io/post/104995https://forum.qt.io/post/104995Sat, 13 Aug 2011 09:24:04 GMT<![CDATA[Reply to Creating wait screen on Thu, 11 Aug 2011 06:57:06 GMT]]>Thanks guys for the answers, atleast now i know what not to try.

@sigrid, if i use QProgressDialog then i will have to use qApp->processEvents(), in order to update the QProgressDialog, and since at the background i am running third party DLL, i can't update QProgressDialog properly.

]]>https://forum.qt.io/post/104495https://forum.qt.io/post/104495Thu, 11 Aug 2011 06:57:06 GMT<![CDATA[Reply to Creating wait screen on Mon, 08 Aug 2011 09:02:39 GMT]]>Also, note that you can use "QProgressDialog":http://doc.qt.nokia.com/4.7/qprogressdialog.html to provide feedback on the progress of a slow operation.

]]>https://forum.qt.io/post/103928https://forum.qt.io/post/103928Mon, 08 Aug 2011 09:02:39 GMT<![CDATA[Reply to Creating wait screen on Sat, 06 Aug 2011 03:54:35 GMT]]>[quote author="mlong" date="1312577075"]You can't display a widget in a separate thread. All GUI elements have to run in the main thread. Your best bet would be to move your processing to a separate thread.

There's a nice "wiki page":http://developer.qt.nokia.com/wiki/Threads_Events_QObjects about threading available too.
[/quote]

Ah, didn't know that, thanks, mlong!

]]>https://forum.qt.io/post/103763https://forum.qt.io/post/103763Sat, 06 Aug 2011 03:54:35 GMT<![CDATA[Reply to Creating wait screen on Fri, 05 Aug 2011 20:44:35 GMT]]>You can't display a widget in a separate thread. All GUI elements have to run in the main thread. Your best bet would be to move your processing to a separate thread.

There's a nice "wiki page":http://developer.qt.nokia.com/wiki/Threads_Events_QObjects about threading available too.

]]>https://forum.qt.io/post/103742https://forum.qt.io/post/103742Fri, 05 Aug 2011 20:44:35 GMT<![CDATA[Reply to Creating wait screen on Fri, 05 Aug 2011 19:18:55 GMT]]>Of course you can push the widget into a new thread. But be mindful about it - you'll need a new class (namely, QThread subclass), and there is the thing of communicating with main thread (your app), which again involves some writing. If you want to go for it, then you might want to prevent your widget from accepting events (it won't need them anyway), which may speed things up a bit in some situations.

IMO, better solution is to leave the widget in main thread, as it won't do much work anyway.

]]>https://forum.qt.io/post/103730https://forum.qt.io/post/103730Fri, 05 Aug 2011 19:18:55 GMT