My program may have several top-level windows open at a time, and I need to send a particular message to all of them (a notification of a change). I know how to do it using the Win32 API, but this is a cross-platform program using wxWidgets. I can't seem to find anything in the wxWidgets documentation about this, but that may simply be because I don't know what to look for.
I can solve this by having each of the top-level windows register itself with the wxApp object when it's created, but that's a manual process that I'm likely to forget on occasion, so I'd rather avoid it if possible. Does anyone know of an existing solution?
There is a global variable wxTopLevelWindows that is a list of the top level windows. See this wxWidgets Discussion Forum thread
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I am programming using C++ /CLI with wxWidgets on Windows 11.
I'm Also Using .NET threads
When I create a wxMessageDialog in a secondary thread and run ->ShowModal() , it works.
But when I create a custom dialog in a secondary thread, running ->ShowModal() pops up a wxWidgets debug alert window :
I tried searching on the wxWidgets forum for the same issue but couldn't find one. I found similar issues but none of them addresses my problem.
I also tried to surround MyCustomDialog->ShowModal() with calls to wxMutexGuiEnter(); and wxMutexGuiLeave(); , but that also didn't work.
I also learned about wxThread while scrolling through the forum but if wxMessageDialog works without me having to create a wxThread, I shouldn't have to create a wxThread myself.
I know I shouldn't be calling GUI methods from a secondary thread, but somehow wxMessageDialog's ShowModal() doesnt have a problem with that.
I would like to know how wxMessageDialog works, and if I can implement the same thing with my custom dialog.
Thank you.
In a few words, no there's no way to use a custom dialog from a secondary thread with current implementation and in the foreseeable future.
Even though your current code works today using wxMessageDialog, there's no guarantee that it will continue to work tomorrow, or on different Windows version or on other OS.
Some more details:
wxMessageDialog and a custom dialog are significantly different internally, even though they represent similar UI features.
wxMessageDialog has native implementation, and you can find its wxMessageDialog::ShowModal() implementation in src/msw/msgdlg.cpp.
A custom dialog will be assembled an run by wxWidgets code, even though the dialog itself and other components are native widgets. You can find wxDialog::ShowModal() in src/msw/dialog.cpp.
If you really want to pursue some experimental development (because it would still not be suited for anything else), and being on Win 11, you could try wxRichMessageDialog. It provides more features than wxMessageDialog and on Vista and later versions it has native implementation, which might go along with your "hack".
But again, using UI from secondary threads will lead to a dead end sooner or later.
I'd like to find both current running programs (or at least program in the foreground) programmatically - and also key events on OS X.
I found inter-application communication guidelines, but they don't seem to say I can find out what applications are running.
I've found key events, but it seems to imply that the current task in the forefront is the one that gets the key events and only if it doesn't handle them does it go up to event chain. I'd like to programmatically intercept them.
Seems dubious, I know. I'm trying to use key events along with screen captures to try to best learn text on the screen - it's for research.
I'm using swift, but I understand that an obj-c example is pretty helpful since they all use the same libraries.
To get a list of running applications use:
NSWorkspace.sharedWorkspace().runningApplications
You can build a key logger (so to speak) by creating an event monitor (same document you linked, just a different section).
I have an OCX without documentation and need to use it.
I've figured out most of the stuff, but, is it possible to monitor all the calls and arguments made by one software to that OCX?
I've tried ProcessMonitor, APIMonitor and none of them give me that information.
I haven't tried it myself, but WinApiOverride seems to support COM object calls monitoring:
http://jacquelin.potier.free.fr/winapioverride32/doc/com.htm
This is a pretty advanced tool, however, and you'll likely have to spend some time adding rules for your specific COM classes.
I wrote an application in a JS-based framework called Titanium. This framework doesn't have some functions, so I'm bundling autohotkeys, and using STDIN/STDOUT to connect the two. Autohotkeys has a cool function DllCall which allows to interconect with the operating system and should help me close the gap between the JS-based framework and the missing functionality.
To give you an example, Titanium allows me to bind to a specific port. But if I bind to 0 and let the OS pick a free port (as it should), it will work, but there's no way to tell which port it actually bound to.
Now since I come from web applications, DLLs are new to me; so I have a few questions:
Is there like a big doc with all the DLLs and all their methods?
How do I know if some methods are dependent on some services? I mean I've heard some rely on RPCs, COM, COM+, WMIs, etc. which a user can turn off and if it does, these methods won't work. Is there also a place where I can get more info on this?
Are there any off-the-shelf DLLs, with their methods, which I can trust that they will work 100% from XP up to 7?
Are there any access permissions I should know about? Are they documented.
If you also come from web programming, is there anything else I should be aware about?
Thank you very much.
You can find a (mostly) complete documentation of all Windows API functions (which reside in DLLs) either online on MSDN or offline using the documentation from the Windows SDK.
For example look at the documentation for SHGetSpecialFolderPath. There you can find various information, like the DLL (shell32.dll), any prerequisites (min. IE 4) and the platform availablity. (min. Windows 2000) Also security considerations are documented.
All API functions are documented more or less in this manner. A good starting point is the Windows Developer Reference. From there you can browse through the many API functions.
Basically the answer to every question is that you should search MSDN for the functions or APIs you are interested in and read the documentation there:
http://msdn.microsoft.com/en-us/library/ms123401.aspx
They document which operating systems the functions are available in so it should be easy to write something that works in Windows XP and up.
I need to find and monitor all the photos on a hard drive or a folder for a photo organizer. Currently I'm doing this naively: recursively traversing, manually marking folders as indexed, and repeating that process to catch when photos are added or moved.
The problem is with a large enough folder tree this is very expensive, so I'm looking for tips to do this differently and/or tips on keeping it a low cpu process.
Ideally solutions would be not platform-dependent.
EDIT: I'm using xulrunner currently, but could compile a module do platform specific stuff.
What about the first run? Is there no solution (even platform-dependent) besides running through the entire folder tree manually.
Ideally solutions would be not platform-dependant.
Impossible. The Win32API has FindFirstChangeNotification, Linux has inotify (and others), Mac OS X has FSEvents, et cetera. This is stuff that's very low-level, and no OS does it the same as any other OS. If you want something cross-platform, you have to find an API with several backends that works on the platforms you want, but if there are any of these, I haven't yet found them.
I don't know of a way to do this in a platform independant way, but on Linux I'd hook into inotify to call something when a file gets added or updated. You could even use inotify-tools to run a script when that happens, so you don't have to be running all the time to capture all these events if they're infrequent. Just have the script update the database, and optionally notify your gallery/display program if it's running.
Are you coding on .NET? If so, you could use the FileSystemWatcher class instead.
Why not user a filewatcher program, which will notify you of changes in particular folder trees?
If you want to write your own you could use the FileSystemWatcher class to do it.
One answer as of 2014 is facebook's watchman: https://facebook.github.io/watchman/
A couple of years ago I ported some functions of Windows API to Linux like (FindFirstChangeNotification, FindCloseChangeNotification ...) it has some limitations but for what you need it could be enough, please take a look at: https://github.com/paulorb/FileMonitor