General callback on main thread
Some time ago I already asked this question, but there was a lot of information and I guess the real question was not really clear. By now I know better what I want:
Post a(ny) callback on the main thread.
Can I achieve this somehow? Something like:
qApp->postEvent(GeneralCallback)where GeneralCallback could be a global function, the result of for instance
the ad hoc hackish way to implement such system that comes to my mind is:
- Create an abstract base class AbstractCallback with a virtual 'callback' function
- Create a class - that inherits AbstractCallback - for each callback function. Add member variables that store the callback arguments and a wrapper function for the actual callback function
- Post instances of these classes to the event queue
- Create an event filter that calls the 'callback' functions of those objects
@Wieland Thank you for a quick response.
I was actually thinking along the same directions. Am I correct to assume that such a approach requires me to create a custom event type using
Additionally, my gut feeling is that creating an event filter on the main event queue (essentially a filter on
qAppI presume?) could cause quite some performance loss. Or am I too pessimistic?
Am I correct to assume that such a approach requires me to create a custom event type
[...] could cause quite some performance loss. Or am I too pessimistic?
Don't know, you'll have to meassure the impact. What I can say is that I used an event filter recently to handle input from a graphics tablet. Processing huge amounts of events in real time was no problem.