netServiceBrowserDidStopSearch not called - cocoa

I'm now writing a Bonjour service listener class, according to the document here:
Currently, it seems working, I can receive "netServiceBrowserWillSearch:" and "didFindService:moreComing:" correctly. However, after a long wait, I cannot receive " netServiceBrowserDidStopSearch:" or "netServiceBrowser:didNotSearch:". Therefore I don't know that is the proper time for my delegate class to stop showing some UI.
Could anyone have an idea for this? Thanks.

NSNetServiceBrowser doesn't stop browsing (and call the -netServiceBrowserDidStopSearch: delegate method) until you explicitly tell it to by calling -stop. After it's found the initial services, it continues informing you as new matching services are added or old ones disappear.
How you handle this depends on how you want your app to behave. If you have a window that continuously shows the available services (e.g. like the Bonjour window in iChat), then it's best to let it continue, and contiuously update the list in response to delegate messages. If you've got more like a dialog that gets populated and then goes away once the user makes a selection (e.g like the system Add Printer... dialog), then you want to keep the browser running while it's displayed, then call -stop once the user dismisses it. If you're waiting to find just one specific service, then you can call -stop once you've found and resolved it.

Related

How to make a Finder Sync Extension change badges in response to outside events

I have a Finder Sync Extension that will display a badge on a file based on the state of a local database. It's straightforward enough to query this database in the requestBadgeIdentifierForURL function, but what if I want the badge to change for a Finder item that's already visible if the state of that database has changed (which can be via a notification through any variety of mechanisms). The documentation (https://developer.apple.com/library/content/documentation/General/Conceptual/ExtensibilityPG/Finder.html) would seem to imply this is possible with this statement:
You might also want to track these URLs, in order to update their
badges whenever their state changes.
The only ways I can imagine this would be possible (and most seem wrong) would be:
call setBadgeIdentifier:forURL from another application that is aware of the change
Launch a thread in the init function of my extension which listens for notifications and calls setBadgeIdentifier:forURL when it receives them
Call some OS API that prompts Finder that the extension should be triggered via requestBadgeIdentifierForURL.
Only the last one seems feasible, and could be managed via the extension informing the outside resource what needs refreshing via the beginObservingDirectoryAtURL/endObservingDirectoryAtURL callbacks, but i don't know what mechanism could do this.

MACOSX - When calling -finishSyncing on an ISyncSessionDriver the app makes repeated calls to the delegate

I'm using Sync Services in my application. I'm using the normal way of getting the contacts from the address book (using sync services).
I want to prematurely end a sync session if the user decides to do that, therefore, when the user presses the "cancel" button, I make a call to [driver finishSyncing]
Attached to the ISyncSessionDriver is a delegate which deals with delegate methods typical of a sync session. One of those methods is - (BOOL)sessionDriver:(ISyncSessionDriver *)sender willFinishSessionAndReturnError:(NSError **)outError
The problem is that when calling finishSyncing, the sessionDriver:willFinishSessionAndReturnError: gets repeatedly called, not just once, but hunderds of times. Eventually it will throw an error.
So, how could I fix this, or what better debugging can I do to figure out what the problem is?
Thanks
Use instead - (void)cancelSyncing.
Make sure to release the receiver soon afterward because you cannot continue using a canceled session.

How can a Mac app determine the method used to launch it?

I have a Mac OS X application that is also a protocol handler (just as, for example, Safari is a protocol handler for the HTTP and HTTPS protocols). So when a user clicks a link of the form myscheme://some-kind-of-info in any application at all, my application launches to handle the link.
Now I need to be able to determine if the application was launched by such a link click, or if it was launched by any other method. In other words, it was launched by any method besides a link click. (In those cases, I want the app to stay open, but if it was launched by a link it should quit and ignore the link. This way it only operates when already running.)
Is there some way within the app at startup to introspect and find out that it was launched by a standard method rather than by an AppleScript GetURL event? I'd like to find out through a documented method, rather than - for example - just have my app only open these links after it's been running for a half a second.
You can register a handler for each of the possible Apple Events you'll get on launch, and make note of which one you receive first.
If the application is launched without documents, you'll get kAEOpenApplication.
If it's launched with documents, you'll get kAEOpenDocuments (or
kAEPrintDocuments).
If it's launched with a URL, then (obviously) you'll get kAEGetURL.
There's also kAEOpenContents, but I wasn't able to trigger it easily in my test app; it's probably worth supporting no matter what.
How Cocoa Applications Handle Apple Events documents all of this stuff.
There is one error in there, though; it says that AppleScript's "launch" will send kAEOpenApplication. It won't, it'll send ascr/noop (kASAppleScriptSuite/kASLaunchEvent, defined in ASRegistry.h). I couldn't get the usual Cocoa event handler mechanism to trap this event, so you may need to do some more digging there.
One way you can check if the event is sent at launch is to register the event handlers in your application delegate's applicationWillFinishLaunching: method; they should deliver by the time applicationDidFinishLaunching: is invoked. With that method, you could potentially only check for kAEGetURL.

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.

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.

Resources