NSRunningApplication 'terminated' not Observable

Question

I'm building a program that launches another program and is then supposed to monitor it, and take action if it terminates. When the application is launched, I can get an instance of NSRunningApplication from NSWorkspace.

Now, the documentation states that NSRunningApplication has the property 'terminated' that is key-value observable. I've tried implementing:

[browserInstance addObserver:self 
                          forKeyPath:@"terminated"
                             options:NSKeyValueObservingOptionNew
                             context:NULL];

And:

- (void)observeValueForKeyPath:(NSString *)keyPath 
                      ofObject:(id)object 
                        change:(NSDictionary *)change
                       context:(void *)context  
{  

        NSLog(@"observeValueForKeyPath");  
        if ([keyPath isEqual:@"terminated"])  
        {  
            NSLog(@"terminated");  
        }  
}

but I never see the observeValueForKeyPath method get tripped. Does anyone know how to make this work, if it is possible? I haven't been able to find any specific examples anywhere online.

If anyone with edit permissions sees this can they please change the title to something a little more relavent, like "NSRunningApplication 'terminated' not Observable" — Stephen Ierodiaconou, Jan 21 '11 at 15:49

score 17 · Answer 1 · answered Jan 24 '11 at 20:07

17

Have you tried the keyPath "isTerminated"?

Notice in the documentation for NSRunningApplication, the property terminated specifies the getter isTerminated, rather than the default getter terminated. (Which makes sense, as a Boolean property "is" or "isn't")

This suggests there may be a bug in obj-c property parsing, where the name of the getter is used for the KVO path.

answered Jan 24 '11 at 20:07

bobDevil

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Thanks! You must observe on `isTerminated`. You my man, have eagle eyes. Excellent catch. Have 50 point-thingys – Stephen Ierodiaconou Jan 25 '11 at 00:03
1

+1 I had this exact question with the `finishedLaunching` key. Just what I needed, ta! – Nick Moore Jan 26 '11 at 17:41

score 4 · Answer 2 · answered Jan 23 '11 at 16:09

I ended up using:

NSNotificationCenter *center = [[NSWorkspace sharedWorkspace] notificationCenter];

    // Install the notifications.

    [center addObserver:self 
               selector:@selector(appLaunched:) 
                   name:NSWorkspaceDidLaunchApplicationNotification 
                 object:nil];
    [center addObserver:self 
               selector:@selector(appTerminated:) 
                   name:NSWorkspaceDidTerminateApplicationNotification 
                 object:nil];

And then implementing the appLaunched and appTerminated methods.

score 0 · Answer 3 · answered Nov 09 '10 at 01:05

0

The “is it plugged in” question: You've verified that browserInstance is not nil, right?

answered Nov 09 '10 at 01:05

Peter Hosey

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I've stepped through the code a few times to make sure everything is set properly. I don't think there's an issue there. – Iain Delaney Nov 09 '10 at 13:58

score 0 · Answer 4 · edited Aug 10 '17 at 14:58

0

Take a look at Apple's Technical Note 2050: Observing Process Lifetimes Without Polling.

TN2050 covers Apple's recommended methods for observing the lifetime of processes you launch, and those launched by others.

edited Aug 10 '17 at 14:58

Robin Andersson

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answered Jan 23 '11 at 21:30

Graham Miln

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1

Yes but this does not answer why KVO is not working on NSRunningApplication `terminated` – Stephen Ierodiaconou Jan 24 '11 at 10:44
I recommend using one of the methods provided by Apple in TN2050. The documented methods deal with edge cases and are Apple's recommended solution. – Graham Miln Jan 25 '11 at 00:08
Note that TN2050 was last revised 2008-09-10 – Perry Jan 15 '16 at 18:18
Unless TN2050 has been superseded, it remains best practice for at least C development. – Graham Miln Jan 15 '16 at 20:16

NSRunningApplication 'terminated' not Observable

4 Answers4