Altering Qt Application keyboard events - events

I'm trying to do the following - given an keypress event in an QT Application, I want to intercept it, modify it (for instance, replacing Qt::Key_Up with 0x81001310), and send it into the app again.
Ideas?

Does overriding the event method work? If you do get all of the keypresses there, just consume the events you wish to replace and send new events that you want.
Might not work, just an idea that should be easy to test.
Be careful to not cause infinite recursions or loops :)
Edit:
If this doesn't work, you can always create an eventFilter and modify the events that way. However, if you do this, you might have to install the event filter for many things.

Related

UWP TimedMetadataTrack Events are not firing

I can not seem to get the a TimedMetadataTrack object to fire the events CueEntered or CueExited for SpeechCue events.
Any thoughts?
So, apparently this line is needed when registering for IMediaCue.CueEntered and IMedia.CueExited events (at least the SpeechCue implementation of the interface):
((Windows.Media.Playback.MediaPlaybackItem)item).TimedMetadataTracks.SetPresentationMode((uint)index, Windows.Media.Playback.TimedMetadataTrackPresentationMode.ApplicationPresented);
This line is required to exactly allow the system to send the CueEntered and CueExited events that are being listened for.
Yet again, another case of Microsoft not fully documenting things in their API Documentation or Code Examples.

How to show a Carbon dialog as part of a plugin for an application with an existing event loop?

I'm writing a plugin for an application and need to use Carbon to show a dialog. I have everything set up including the event handler, but I cannot possibly call RunApplicationEventLoop() because this would stall the host application.
How can I fix this? Will I need to create a separate thread and call RunApplicationEventLoop() from there?
-Joe
What makes you think you need to call RunApplicationEventLoop? The host app is presumably running an event loop, probably either using RunApplicationEventLoop or NSApplicationMain. By the way, would your dialog be modal? Modal is easier.

NSDocumentController not quitting app properly on review unsaved documents in Cocoa/Objective-C

I've been banging my head on walls trying to solve this.
My app uses a subclass of NSDocument, NSDocumentController and also NSWindowController. The issue is that when I create a document and make a modification, and also if I create more than one document the same way, if I choose Quit while documents are unsaved, I get the proper dialogs to ask wether I want to Review unsaved docs, Cancel or Not save, but whenever I select to Review and then save a document, I get to save, but after saving the first document, first, that document is NOT closed, and I am not asked to save the others. On top of this, My App's Quit menu item becomes grayed out.
I created another skeleton app to do the same thing, and of course, all works normally. I checked my connections in the nib file, and cannot see anything wrong, or different from the test app. Although there is a lot more in my app.
I am not currently overriding the reviewUnsavedDocumentsWithAlertTitle:cancellable:delegate:didReviewAllSelector:contextInfo: method, but when I do, I get the same problem, since I call Super's version of it after doing some special clean-up work. But again, not overriding this yields the same result.
One thing I do notice, is that in my own App, I get the following messages in the Log as I run it, which I do not get in my test app:
[Switching to process 9997 thread 0x7667]
[Switching to process 9997 thread 0x903]
Which makes it look like I am doing something multi-threaded here without knowing. My test app doesn't switch to another thread.
I'm not sure how to check if all my connexions are ok and why these threads are being switched to and where they come from.
Since I get the error wether or not I override the NSDocumentController methods like the one above or the closeAllDocumentsWithDelegate:didCloseAllSelector:contextInfo: I imagine the error comes from somewhere else.
Maybe my NSDocument subclass's saving methods are creating the issue, but they return the appropriate values once the save has occurred, I get no error and the files are all fine.
I'd like to override the -didCloseAllSelector or -didReviewAllSelector, but I'm a bit challenged with this. I'm not sure how to build the method, since this:
- (void)documentController:(NSDocumentController *)controller
didCloseAll:(BOOL)didCloseAll contextInfo:(void *)contextInfo;
{
NSLog(#"All documents closed");
}
is never called. Is this a symptom? Tried the same for the -didReviewAllSelecter which never gets called.
Finally, I was overriding a method in my "NSDocument" subclass which I should not have. Removing this fixed it.
I guess you have to be really careful what you override!
The method was writeToFile:ofType:originalFile:saveOperation: which I no longer had to do.
Not sure exactly what was wrong, but it may help others to know to look there.

Is there an API event for when person changes clock on Windows?

I was wondering if there's some sort of system event that gets fired every time a user changes the time in Windows. I know there's a way to enable this in Windows' EventLog, but I was looking for a way to respond to this event programatically (like using the Windows API).
A WM_TIMECHANGE message is sent whenever there is a change in the system time
I'm not sure from your question if you're working in managed or native code. But if you're working in managed code you can use the TimeChanged event on the SystemEvents class.
Microsoft.Win32.SystemEvents.TimeChanged

Session 0 Isolation

Vista puts out a new security preventing Session 0 from accessing hardware like the video card, and the user no longer logs into session 0. I know this means that I cannot show the user a GUI, however, does that also mean I can't show one at all? The way my code is set up right now, it would be more work to make it command line only, however if I can use my existing code and just programmatically manage the GUI it would take a lot less code.
Is this possible?
The article from MSDN says this:
• A service attempts to create a user interface (UI), such as a dialog box, in Session 0. Because the user is not running in Session 0, he or she never sees the UI and therefore cannot provide the input that the service is looking for. The service appears to stop functioning because it is waiting for a user response that does not occur.
Which makes me think it is possible to have an automated UI, but someone told me that you couldn't use SendKeys with a service because it was disabled in Session 0.
EDIT: I don't actually need to show the user the GUI
You can show one; it just doesn't show up.
There is a little notification in the taskbar about there being a GUI window and a way to switch to it.
Anyway, there actually is a TerminalServices API command to switch active session that you could call if you really needed it to show up.
You can write a separate process which provides the UI for your service process. The communication between your UI and service process can be done in various ways (search the web for "inter process communication" or "IPC").
Your service can have a GUI. It's simply that no human will ever see it. As the MSDN quote suggests, a service can display a dialog box. The call to MessageBox won't fail; it just won't ever return — there won't be anyone to press its buttons.
I'm not sure what you mean by wanting to "manage the GUI." Do you actually mean pretending to send input to the controls, as with SendInput? I see no reason that it wouldn't be possible; you'd be injecting input into your own program's queue, after all, and SendInput's Vista-specific warnings don't say anything about that. But I think you'd be making things much more complicated than they need to be. Revisit the idea to alter your program to have no UI at all. (That's not the same as having a console program. Consoles are UI.)
Instead of simulating the mouse messages necessary to click a button, for instance, eliminate the middle-man and simply call directly the function that the button-click event would have called.

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