I use sharekit with mail/twitter/facebook and I am really new to objective-c. sharekit works well and sends my images like it should.
in my app I have a screenshot function. I want the app to 'freeze' when a screenshot is taken, stopping to send any shake- or touch-event to the scene behind the sharekit-action.
in my screenshot-layer I have three buttons which call the shareItem-methods of their specified service, like
[SHKTwitter shareItem:item];
vereything works fine 'till here. but now when the sending is finished (or canceled or errored) I need the app to 'unfreeze', sharekit should tell my app that it is allowed to listen to any touch- or shake-action again.
I am sorry but I think I don't understand the concept of using the delegate here. I mean, is 'sendDidFinish' meant to be inside a delegate? and if so, how could I tell sharekit who is its delegate? or do I have to edit the send-service classes (like SHKItem or SHKFacebook) itself?
please don't downrate me for this question. I really want to get behind this mystery...
SHKTwitter inherit from SHKOAuthSharer, who inherit from SHKSharer. SHKSharer has a delegate protocol called "SharerDelegate".
So you can use an instance of SHKTwitter, then set it's delegate as :
shkTwitterInstance.shareDelegate = yourDelegateObject.
And implement the delegate method
- (void)sharerFinishedSending:(SHKSharer *)sharer;.
Try that.
EDIT (OTHER, AND MORE POPULAR, SOLUTION)
Also, you can suscribe your object to "SHKSendDidFinish" notification from SHKTwitter object.
[[NSNotificationCenter defaultCenter] addObserver:yourObject selector:#selector(theMethodthatYouWantToExecuteWhenTheNotificationIsRaised:) name:#"SHKSendDidFinish" object:shkTwitterObject];
Related
I'm not very sure how Document-Based Applications works.
I've created some actions for NSObject in the Mainmenu.xib. One of this is called when the user click on "File>new":
-(IBAction) newDocument:(id)sender{
Document* newDoc =[[Document alloc] init];
[[NSDocumentController sharedDocumentController]addDocument:newDoc];
[newDoc addWindowController: [[NSWindowController alloc] initWithWindowNibName:[newDoc windowNibName] owner:newDoc]];
[newDoc showWindows];
}
I've also this code inside the openDocument:(id) sender action that does the same but of course loading data to define the application workspace.
If I run the application it show a blank document without to call newDocument action. I don't know how to stop default blank document and to set newDocument: to be called.
Then if i do openDocument: too (so I've two documents, one blank and one not) and I do some operation on the second document it also replicate in the first blank one.
I've double check delegates, file owners, and also if the - (void)windowDidBecomeMain:(NSNotification *)notification return different pointers and all seem to be ok.
Probably I've not understood document based application work flow but I've read the Apple guide and other istructions. What do I miss?
An IBAction method is called, when the user did something. So this is not called from the system at app launch.
You can customize the behavior at app launch with -applicationShouldOpenUntitledFile: (NSApplicationDelegate) and – this is probably your next question – -applicationShouldHandleReopen:hasVisibleWindows: (NSApplicationDelegate). Changing the behavior in both cases is not recommended.
Looking to your action method, I see no reason, why you want to customize it.
A instance of your document class is created automatically.
You can create a window controller for it in your document subclass. This is documented.
Just let NSDocumentController do the work for you. What is the problem of the default behavior?
No. I thought to be confused instead the only problem was about releasing observer notification. When you call the close message for a NSDocument notification observers still persist. Working in ARC I miss this point.
So This is the solution at my issue. Thank you anyway.
i have been working on moving one of my apps away from the "shared appdelegate" process which seems to be frowned up, despite its over whelming use. i have been attempting to setup protocol methods for what i want to do but am having zero luck. my question is, can you even have lets say a single viewcontroller send delegate requests to multiple classes? from what im finding out it doesn't seem like you can. which doesn't make sense because i thought that was the whole point of delegates and protocols with mvc. now just to clarify, i know you can have a single viewcontroller act as the delegate for multiple other viewcontrollers. but that's not what i am asking. for a simple example, lets say you have apples flip-utility template. the "done" button just calls a delegate method to the mainvc to dismiss it. now lets say we added a new class called...
#interface NewClass : NSObject <TheOtherDelegate>
and it had a delegate method...
- (void)doSomething
{
NSLog(#"The Delegate did something...");
}
can we have a button on the flipsideviewcontroller, that we wanted to call that delegate method, but still keep the "done" button call to the delegate method on the mainviewcontroller that dismisses it?
that being said, i put together a quicky project just to see if it would work and it doesn't. i came across an "answer" that says you have to instantiate the class first you want to be the delegate...
NewClass *myDelegate = [NewClass alloc] init]
[fillInMethodHere setDelegate:myDelegate];
not sure why it got a correct answer check, because needless to say it doesn't work. is there something i am missing? i scoured ib to see if there is some "delegate" connection somewhere but i couldn't find anything.
on a side note, as i was working in my working project, i read a suggestion about removing the #import and adding #class. again, that broke all kinds of things. the strange thing is before doing that, what i had so far was working and building fine. when i removed the new #class and un-commented the #import. xcode all of a sudden gave me an error "cannot find protocol deceleration for..." but yet, it worked seconds earlier. i would up having to remove the protocol code and re-add it for it to work again. very starge.
any help would be appreciated. everything iv read in docs, google, stack, etc that say something should work, don't in an actual project.
A "delegate" isn't some fancy object. It's simply a synthesized property of type id called delegate. If you wanted to, you could have an arbitrary number of properties that all conformed to the same protocol. Then when you wanted to issue a callback, you would just address all of them:
[self.mydelegateA doSomething];
[self.mydelegateB doSomething];
etc.
You could also have an NSMutableArray property that you could add objects to, and then use [self.myMutableArrayOfDelegates makeObjectsPerformSelector:#selector(doSomething)].
Finally, there's always the route of NSNotificationCenter (not to be confused with push notifications) is a class that provides an inter-object messaging system. Many objects can register for a message that any other object can send.
Please see the Apple's documentation for more information. Click Here.
Regardless of the fact that this is OS X documentation, it's still quite good at explaining things visually: click here.
Here's an example of simply changing the name of the delegate property: click here
And here's an example of adding another protocol and a second delegate: click here
Finally, here's an example that builds on the previous two and has a third delegate that also conforms to the same protocol: click here
I'm stuck on this step of developing an XCode application: https://developer.apple.com/library/mac/#documentation/General/Conceptual/Mac101/Articles/07_WhereNext.html
What I'm confused about is the role of the AppDelegate class that's created by default when creating a project initially in XCode 4. If I implement a custom controller, let's use the example link above and call it TrackController. Do I make that controller the app delegate? It seems any tutorial I read isn't very clear on this.
So, in AppDelegate, do I create a new instance of the controller class here? And if so, do I then hook up the outlet here? Or do I change the File's Owner to be the controller class? If that's the case, then how's that done in XCode 4?
Not a very well defined question I know, but I'm sure someone knows what I'm talking about.
EDIT
The following screenshot shows what I mean. The blue box is now "Track Controller". I've shown the AppDelegate class in this case though to make it clear. What do I use, AppDelegate.m, or TrackController.m? How should it be done?
EDIT 2
Going back to this, I've uploaded the code to GitHub here as I still haven't figured out how to hook everything up.
To re-explain, I need to figure out how AppDelegate and TrackController all relate and communicate with one another. The concepts are generally new to me and I've read the Apple documentation but they haven't really helped me. I've even had in-depth discussions with experts and I still fail to see how it should work.
My model is Track, then I have TrackController and of course AppDelegate. AppDelegate is instantiating TrackController and I was hoping that it'd be able to open up its window.
What am I doing wrong? Hopefully an expert can help me!
What it's describing is that the application delegate should focus on handling the delegate calls sent to the app.
You actually create a new class to act as the primary controller of the app, and then you add code to call it when the app is finished loading. From there on out, that app is (supposedly) your primary control point (except, of course, when it 'hands off' to another class).
I'm more familiar with how the process works on iOS than Macs, which have to worry about windows, but for an iOS app you'd add code to call your starting view controller from inside ApplicationDidFinishLaunching:WithOptions:. From there, the view controller takes off, and the easiest way to view the entire process is that you start at the view controller (that's how most tutorials handle it, in fact, letting XCode handle the fact that the app delegate creates that view controller).
I'm trying to use a NSProgressIndicator (indeterminate) inside of a statusbar-menu. I'm using an NSView-object as view for the menuitem, and then subviews the progress indicator to display it. But whenever i try to call the startAnimation: for the progress, nothing happens. When i try do the very same thing on a normal NSWindow it works perfectly, just not when inside a menuitem.
I'm new to both cocoa and objective-c so I might've overlooked something "obvious" but I've searched quite a bit for a workaround but without success. I found something about menuitems cant be updated while shown and that you need to use a bordeless window instead. But I have not been able to confirm this in any documentation.
Edit:
Ok, almost works now. When using the setUsesThreadedAnimation: and from a MenuDelegate's menuWillOpen and creating a new thread. This thread runs a local method:
-(void) doWork(NSProgressIndicator*) p{
[p startAnimation:self];
}
This will start the progressindicator on a random(?) basis when opening the menu. If I call startAnimation: directly without going through doWork: (still using a new thread), it never works. Doesn't setUsesThreadedAnimation: make the progress-bar create it's own thread for the animation?
Solved it by using:
[progressIndicator performSelector:#selector(startAnimation:)
withObject:self
afterDelay:0.0
inModes:[NSArray
arrayWithObject:NSEventTrackingRunLoopMode]];
Inside the menuWillOpen:, the problem seems to have been calling startAnimation: before the progressbar was finished drawing itself.
How are you referencing the NSProgressIndicator that is in the view (and the one in the window, for that matter)? For example, do you have a controller class that has IBOutlet's hooked up to the progress indicators? If you are using an IBOutlet, are you sure it's hooked up properly in the nib file?
Also, where and when are you calling startAnimation:? (We need to see some code).
One thing that can sometimes happen is that you forget to hook up an IBOutlet in the nib. Then, when you attempt to tell the object to do something in code at runtime, the IBOutlet is nil, and so what you think is a message being sent to your object is in fact, a message being sent to nil. In other words, it's just ignored, and effectively looks like it's not working.
Provided you do have a (potentially) valid reference to the UI object, the other common issue you'll see is when a developer is trying to send a message to the object at "too early" of a time. In general, init methods are too early in the controller object's lifetime to be able to send messages to user interface objects—those IBOutlet's are still nil. By the time -awakeFromNib is called, IBOutlet's should be valid (provided you hooked them up in IB) and you can then send the message to the UI object.
Have you told it to use threaded animation via -setUsesThreadedAnimation:?
I've been thinking about this and have read through another stackoverflow question regarding the best recommended way to communicate between view controllers. However, the question/answer for that doesn't seem to address the best approach for the reverse behavior.
i.e. to pass data from ParentController to its ModalController, we could initialize ModalController like initWithDataToProcess:.
But what if we want to do the reverse? How would I notify the previous controller about a new data?
e.g. User clicks on 'new person' button on the ParentController. I initiate a new ModalController and present the user with a person editor view via presentModalViewController:. User clicks on 'done' to add a new person. I dismissModalViewController: and UI returns to the ParentController's view.
Using a global field reference in a singleton object (app delegate or other) is bad. delegation (via formal protocol) and notifications (via NSNotificationCenter) seems overkill. Any suggestions?
It is generally cleaner to use notifications. Just add your observer like this....
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(somethingHappened:) name:#"MyNotification" object:nil];
and elsewhere in your code you'd post the notification whenever you need to.
[[NSNotificationCenter defaultCenter] postNotificationName:#"MyNotification" object:self];
In the example I'm passing self but you can pass any object you wish really and it will be fed to your somethingHappened: function
The important thing is to keep the #"MyNotification" very descriptive and unique. Adding your project name to the beginning is a good way to keep things unique...eg. #"ProjAXViewHasGotData"
A delegate is pretty much the minimum you can do. If you think it is too much of a hassle to declare a new protocol for this, just pass in the parent view controller and have the modal one call a method on it.