QSplashScreen - Extend loading time to display splash for longer?

Gavin Harper · 04-07-2011, 01:37 AM

Hello,

One requirement of a project I am currently working on (for Maemo) is that the Qt application displays a QSplashScreen when it loads.

My issue is that the application is fairly small and I have written it to load components etc as they are required rather than at start-up. This has lead to quick start up times (which, in a perfect world is what we all strive for!)

How would I intentionally delay the start-up time so that the splash shows for longer?

I have investigated

Quote:

QTimer:: oneShot() (Space added to prevent smiley)

however, its prototype dictates that it be connected to a slot. I am running this QSplashScreen from inside main so this is neither needed nor feasible.

What is the best way to essentially do this:

Code:

Display Splash
Timer for 3 seconds
Close Splash
Display mainWindow

I do not want to use native system calls such as sleep() and would instead rather a Qt based solution.

Thank you for your advice

rtmistler · 04-08-2011, 10:58 AM

The QSplashScreen is not going to go away until you start you main event loop. In fact, I have the opposite gripe which is that instead of using showMessage() to put up progress text, I'd rather use a timer to swap between 3 or 4 splash screens that have a rotating widget so that the user sees that the application is working while loading. A form of animation. However since the main event loop has not yet been run, I also cannot use any timers, they will never time out.

So my first recommendation here is that you do use sleep or nanosleep inline to get that delay. Or you can try sending a signal to your Qt application from another process that you are waiting for to be completed before you show your main screen. I'm not sure if that will work, "within the Qt library" because of that main event loop issue; however if you use straight C and wait on a Linux signal, then it may work.

My assumption was that you wanted to delay the Qt main window to wait for other processes; however in re-reading you're saying that it's super fast and you do not wish the splash screen to be so rapid that no one notices it.

A.) What's the big deal? Everyone I know wants the main window up ASAP.
B.) If this is a requirement or a sincere want on the part of the project where the splash screen shows branded information and/or copyrights, then just use sleep and stop trying to be Qt. (Hey, I can actually use a pun correctly there. I still pronounce it que-tee, but Nokia/Digia wants to pronounce it as "Cute")