Mac / Cocoa - Getting a list of windows using Accessibility API

Question

I want to use the Accessibility API to get a list of all windows for a given application (external).

The goal is to check if a certain window is open. First I check that the application is running (using [NSWorkspace runningApplications] and checking each one), and then I want to check the title bar text of each window that is open for that application.

PS

So I can create an element for the app using the PID:

AXUIElementRef app = AXUIElementCreateApplication(pid);

but what do I do with it? Am I even going in the right direction? Can't beleive it's so hard to find examples on this.

Answer 1

I don't know a way to get window ID and PID from the Accessibility API.
The NSWindow method Laurent mentioned only provides Window IDs but not the PID of the window owning application.
I would use the CGWindowList methods that are available since 10.5.
To get a list of window IDs and the PID of the owner you can try the following:

CFArrayRef windowList = CGWindowListCopyWindowInfo(kCGWindowListOptionOnScreenOnly, kCGNullWindowID);
for (NSMutableDictionary* entry in (NSArray*)windowList) 
{
    NSString* ownerName = [entry objectForKey:(id)kCGWindowOwnerName];
    NSInteger ownerPID = [[entry objectForKey:(id)kCGWindowOwnerPID] integerValue];
    NSLog(@"%@:%d", ownerName, ownerPID);
}
CFRelease(windowList);  

You can control if you want all windows (including offscreen, ...) with the option paramter.
Also the entry objects contain a lot more information. Documentation link