Re: -viewDidMoveToWindow without subclassing? NSViewController?
On a general note, if you want something to happen later than - awakeFromNib, you can always send - performSelector:withObject:afterDelay:cancelPrevious:. If you pass a delay of zero, it will happen the next time through the event loop. I've used this many times to deal with situations similar to what Jerry described. -jcr "This is not a book to be tossed aside lightly. Rather, it should be hurled with great force." -Dorothy Parker ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: -viewDidMoveToWindow without subclassing? NSViewController?
On 17/04/2009, at 1:43 AM, Jerry Krinock wrote: The other way around, Graham. I need the window controller, so I get it from -window. See below. I don't see why you need to get this from an item in a tab view? You talk about the need to initialise something. What? How? What are you trying to do? In general, I need the document during initialization, so I do [[[aView window] windowController] document] Here are two examples of why I need the document: * In an NSPredicateEditor subclass, during -viewDidMoveToWindow, creating the row templates requires a reference to the document's managed object context, so it can get attribute types. See code [1]. * In an NSOutlineView subclass, during -viewDidMoveToWindow, I need to initialize and set a data source, which needs a (weak) reference to the document in order to get data objects. See code [2]. Is this an abnormal design pattern? I think I've seen people set their document as nib File's Owner, but I can't do that since my document is sometimes instantiated without a window. My nib File's Owner is a window controller. This does sound like an abnormal design pattern. The controller should be in charge, so going from view -> window -> controller -> document seems backwards. The controller's initialization (whether at awakeFromNib or windowDidLoad time) should be handling this, so you can do self -> document to access the document. The controller is responsible for forging the necessary links and set up between any views it knows about and the document. The view definitely shouldn't be doing this, the controller definitely should be. I've not used NSPredicateEditor, so I'm not familiar with it, but as a view it shouldn't be talking directly to the data model. Instead, the controller should give it what it needs as appropriate. The same pattern definitely applies to NSOutlineView, which I am familiar with. The controller is typically its datasource, which you can set in IB. The controller then gathers data from the "real" datasource (the document, say) and presents it to the view. Effectively the controller proxies the data from the document on demand. This approach requires no special initialisation - the NSOutlineView won't ask for data until it's ready to display it, at which point it must by definition be visible and in a window. The controller can then just fetch (and possibly cache) data from the document and return it to the outline view in the usual way. I'd be surprised if the same technique would be inappropriate for the predicate editor also. Trying to hook into certain moments like when a view is moved to the window sounds error prone, tricky, and unnecessary. I've never found the need to do that sort of thing using window controllers - let the views come to the window controller for their data, and let the window controller be in charge of obtaining it. It seems like you're trying to short-circuit the controller and simply using it to make a direct connection between the document and the view - this is probably where you're going wrong. Place the controller in the data pathway, don't just use it to make a pathway directly between data model and view. --Graham ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: -viewDidMoveToWindow without subclassing? NSViewController?
On 2009 Apr 15, at 22:14, Michael Ash wrote:
IMO that's a silly objection. Subclassing and adding this method is
easy, straightforward, and it works. You only need to override one
method to justify having a subclass.
Thanks Michael. I decided to subclass the view that needs the
initialization (NSPredicateEditor) instead of the tab view item's
content view. So now it has some other code, relocated from the
window controller. But it's the same idea.
I'm still having trouble with NSPredicateEditor's -
viewDidMoveToWindow, though. But before I pursue that I'd like to
continue discussion of Graham's comment, to make sure I'm on the
beaten path...
On 2009 Apr 15, at 20:09, Graham Cox wrote:
Views that are not in the currently selected tab are not in the view
hierarchy ... [notShownView window] is always nil. It doesn't matter
when you call it - if it's not visible in the selected tab you can't
find the window that way.
Conversly, when a tab is visible, any visible view in it will return
the valid -window. Since I only need it once, during initialization,
I grab it during -viewDidMoveToWindow.
If you need the window, the window controller will return it from -
window.
The other way around, Graham. I need the window controller, so I get
it from -window. See below.
I don't see why you need to get this from an item in a tab view?
You talk about the need to initialise something. What? How? What are
you trying to do?
In general, I need the document during initialization, so I do
[[[aView window] windowController] document]
Here are two examples of why I need the document:
* In an NSPredicateEditor subclass, during -viewDidMoveToWindow,
creating the row templates requires a reference to the document's
managed object context, so it can get attribute types. See code [1].
* In an NSOutlineView subclass, during -viewDidMoveToWindow, I need
to initialize and set a data source, which needs a (weak) reference to
the document in order to get data objects. See code [2].
Is this an abnormal design pattern? I think I've seen people set
their document as nib File's Owner, but I can't do that since my
document is sometimes instantiated without a window. My nib File's
Owner is a window controller.
Jerry
[1] In implementing a subclass of NSPredicateEditor...
- (void)viewDidMoveToWindow {
// To make sure this only runs once...
if ([self isInitialized]) {
return ;
}
[self setIsInitialized:YES] ;
NSManagedObjectContext* moc = self window] windowController]
document] managedObjectContext] ;
NSEntityDescription* entityDescription = [NSEntityDescription
entityForName:@"Stark_entity"
inManagedObjectContext:moc] ;
NSArray* rowTemplates = [self
templatesWithAttributeKeyPaths:keyPaths
inEntityDescription:entityDescription] ;
[self addRowTemplates:rowTemplates] ;
...
}
[2] In implementing a subclass of NSOutlineView...
- (void)viewDidMoveToWindow {
// To make sure this only runs once...
if ([self dataSource]) {
return ;
}
// Create and set data source
Bookshelf* document_ = [[[self window] windowController]
document] ;
ContentDataSource* dataSource = [[ContentDataSource alloc]
initWithDocument:document_] ;
[self setDataSource: dataSource] ;
[dataSource release] ;
// Set the doubleclick action.
[self setTarget:[[[self window] windowController] document]] ;
[self setDoubleAction:@selector(visitItems:)] ;
...
}
___
Cocoa-dev mailing list (Cocoa-dev@lists.apple.com)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com
This email sent to arch...@mail-archive.com
Re: -viewDidMoveToWindow without subclassing? NSViewController?
On Wed, Apr 15, 2009 at 10:09 PM, Jerry Krinock wrote: > I have the contentView of an NSTabViewItem controlled by an > NSViewController. I need to run code in there to initialize things when the > nib is loaded, but not before the view has a -window. > > Putting the code in -awakeFromNib is no good because it will not yet be in a > window if another tab is selected during nib loading. I believe it would > work to subclass the content view and implement -viewDidMoveToWindow, but > that seems silly since it would be the only code in this subclass. IMO that's a silly objection. Subclassing and adding this method is easy, straightforward, and it works. You only need to override one method to justify having a subclass. Mike ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: -viewDidMoveToWindow without subclassing? NSViewController?
On 16/04/2009, at 12:59 PM, Jerry Krinock wrote: On 2009 Apr 15, at 19:15, Graham Cox wrote: The usual way is to implement -windowDidLoad (a NSWindowController method) and put your code in there. This is called when the window is first shown by the window controller, since windows are constructed lazily. Thanks Graham, but after trying this I discover that it suffers from the same problem as -awakeFromNib. Indeed it runs later than - awakeFromNib, but still not late enough because [self window] still returns nil in views that are not in the initially-selected tab view item. Isn't this always going to be the case with NSTabView? Views that are not in the currently selected tab are not in the view hierarchy - the tab's "container" view is retained by the tab but not added to the tab view itself unless selected, so there is no path from any hidden view item to the window - [notShownView window] is always nil. It doesn't matter when you call it - if it's not visible in the selected tab you can't find the window that way. If you need the window, the window controller will return it from - window. I don't see why you need to get this from an item in a tab view? You talk about the need to initialise something. What? How? What are you trying to do? --Graham ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: -viewDidMoveToWindow without subclassing? NSViewController?
On 2009 Apr 15, at 19:15, Graham Cox wrote: The usual way is to implement -windowDidLoad (a NSWindowController method) and put your code in there. This is called when the window is first shown by the window controller, since windows are constructed lazily. Thanks Graham, but after trying this I discover that it suffers from the same problem as -awakeFromNib. Indeed it runs later than - awakeFromNib, but still not late enough because [self window] still returns nil in views that are not in the initially-selected tab view item. ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: -viewDidMoveToWindow without subclassing? NSViewController?
On 16/04/2009, at 12:09 PM, Jerry Krinock wrote: I have the contentView of an NSTabViewItem controlled by an NSViewController. I need to run code in there to initialize things when the nib is loaded, but not before the view has a -window. Putting the code in -awakeFromNib is no good because it will not yet be in a window if another tab is selected during nib loading. I believe it would work to subclass the content view and implement - viewDidMoveToWindow, but that seems silly since it would be the only code in this subclass. It seems like NSViewController should give me a "view has moved to window" notification or delegate message, but I can't find any. There is a -loadView, but Cocoa does not invoke it when loading or moving the view. Is there a better way -- or, what have I done wrong? The usual way is to implement -windowDidLoad (a NSWindowController method) and put your code in there. This is called when the window is first shown by the window controller, since windows are constructed lazily. --Graham ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
-viewDidMoveToWindow without subclassing? NSViewController?
I have the contentView of an NSTabViewItem controlled by an NSViewController. I need to run code in there to initialize things when the nib is loaded, but not before the view has a -window. Putting the code in -awakeFromNib is no good because it will not yet be in a window if another tab is selected during nib loading. I believe it would work to subclass the content view and implement - viewDidMoveToWindow, but that seems silly since it would be the only code in this subclass. It seems like NSViewController should give me a "view has moved to window" notification or delegate message, but I can't find any. There is a -loadView, but Cocoa does not invoke it when loading or moving the view. Is there a better way -- or, what have I done wrong? Jerry ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
