I'm having a problem with a custom NSPopUpButtonCell in a table that's instantiated when the table view is populated via bindings and a NSArrayController.
The pop up button cell is created but when attempting to access the outlet by overriding the pop up button cell's setMenuItem:item method it's nil.
Is this the expected behaviour..?
Should another method be used to replace the menu at creation time?
Basically I need the outlet to link back to my controller (NSWindowController) for that document window so I can customize the NSPopUpButtonCell menu accordingly from the custom popup button when it's populated.
A solution using bindings would be even better - but when overriding setObjectValue: I can see it's only never called with a nil parameter.. using a stock NSPopUpButtonCell results in a properly populated pop up menu, though.
(see also Why is NSPopUpButtonCell showing correctly when only setObjectValue:nil is called).
You don't need to override anything to populate an NSPopUpButtonCell in an NSTableView column. The thing to know is that you set the bindings on the NSTableColumn and not on the cell itself. Typically, you would have an NSArrayController in your xib that is bound to an NSArray containing all the options for the pop-up, and then you would select the column with the pop-up cell and go to it's bindings. Like in this screenshot (note the populated Content, Content Objects, and Selected Object bindings in the inspector on the right):
If you want a working example, you can check out this project I whipped up for another StackOverflow question. There's a bunch of unrelated stuff pertaining to making the NSPopUpButtonCell use NSAttributedStrings, but the bindings in the xib constitute a working example of how to bind an NSTableColumn with a pop-up whose options are populated by bindings.
Related
I have an NSSplitView showing two NSTableView instances. I need to detect which table view has become "active" (of focused), which means the one that the user has clicked. I need to know that because each table view acts as a source list for another view that shows the content of the selected row(s). This other view is shared for both tables.
I could do it by subclassing NSTableView and reacting to mouseDown: or another method but it I'd rather avoid subclassing just for that. I also don't want to track any NSWindow event just to know if the user has clicked one of the tables (I'd rather subclass NSTableView).
Currently, I use the delegate method tableViewSelectionDidChange:, but this method is, obviously, only called when the selected row changes. I need to know that a table becomes active even if the selected row hasn't changed.
Observing the clickedRow property of the table views doesn't appear to work. If may not be KVO compliant.
Any ideas?
For those interested, the most convenient solution I found was to take advantage of the fact that NSTableView is a subclass of NSControl. So just like NSButton it can send action messages when clicked (upon mouse up).
For each tableView, I wired its "action" to the same ibaction selector of my controller object in interface builder.
The controller identifies the sender and acts accordingly.
No need to subclass NSTableView.
I've a hard time getting my Cocoa application to work as expected. It consists of a toolbar in the main.nib and a custom view in a details.nib file. Now I want the user to select an entry in a NSPopupButton in the toolbar and the content of the custom view should be changed accordingly.
To achive this I've added an ArrayController to my main.nib, showing the following configuration:
Furthermore the Managed Object Context is bound to the Model Key Path delegate.managedObjectContext (it is no document based application).
With this configuration the NSPopupButton works just fine and if I add a Label to the toolbar (also in the main.nib) and bind it's value to the selection (Controller Key), name (Key Value Path) the content is refreshed whenever I change the selection.
The Bindings of the NSPopupButton look like shown in the following screenshot:
So in my details.nib I tried the following to achieve the same effect. I've added an ArrayController, whichs Managed Object Context is also bound to the Model Key Path delegate.managedObjectContext. Also the configuration is exactly the same as shown in the above pictures. I've then added a label and bound it's value to the selection (Controller Key), name (Key Value Path) of this ArrayController.
The problem is that the Label only displays the the initial selection after the application did launched correctly. Afterwards, when I change the selection of my NSPopupButton, the label does not change accordingly.
What are my options to get the ArrayController working accross multiple NIB files?
BTW: I've tried to follow this blog post to get it working but it seems I'm missing something here.
Update:
If I replace the Label in the details.nib by a NSTextField and change the text of it, the changes are reflected in the related NSPopupButton entry. So I guess I made something right, but the main problem remains: I can only edit the entry which was loaded during application startup. Switching to another NSPopupButton entry does not change the text in the NSTextField.
Update 2:
I've created a small sample project with exactly the same configuration and uploaded it on GitHub. So feel free to check it out or create a pull request with a solution approach.
It seems you're missing the fact that, when you create the second array controller on the Details.xib it has no relation to the array controller on the MainMenu.xib. They are two separate instances.
When you change the selection on the PopUp the only array controller affected is the one on MainMenu.xib.
You have several options here:
When you create your DetailViewController pass a reference to the array controller on the Controller and bind to that (don't create a new one on the details.xib)
Just use simple KVO to observe the selection on Controller, and programatically change your label value.
Just use simple KVO to observe the selection on Controller and update the array controller on the DetailsViewController to keep them in sync.
your solution here...
As long as you understand what's going on I'm sure you'll find the best solution to your original problem.
Setup
I have a NSCollectionView. I have a checkbox in the View Prototype. I've successfully set up bindings so the Card Title and action get populated. (image 1, below)
Goal
I'd like, when I click the checkbox, to run a function that accesses the specific CardModel that the View Prototype is already able to access. I'll then manipulate its data accordingly.
Research
I found this article on SO: Get the representedObject values of NSCollectionViewItem NSButton click, which describes my situation pretty well. The answer, unfortunately, is without specific code. Here's what's suggested:
So, first, set the represented object of your button's cell to the
collection view item that owns the button. (You can do this in the nib
editor.) Then, in your action method, get the button's cell, then the
cell's represented object (which is the item), then the item's
represented object.
Seems simple enough, right?
Attempted Solution(s)
I create a method cardCheckBoxClicked: and connect it to the checkbox.
As per the advice above, I connect the button cell's outlet representedObject to Card Collection View Item. (image 2)
I then attempt to get the Card Collection View Item's representedObject in code.
From MainWindowController.h:
-(IBAction)cardCheckBoxClicked:(id)sender
{
CardModel* cModel = [[sender representedObject] representedObject];
NSLog(#"card title: %#",cModel.title);
}
Error
When I click on the checkbox, I get the following error:
-[NSButton representedObject]: unrecognized selector sent to instance 0x6080001581b0
Question!
So - how do I access the button cell's represented object? Did I misunderstand the advice given above? How can I successfully access the data I need?
Images (reference)
bindings example
represented object connection
This here:
-[NSButton representedObject]:
Is you asking the Class NSButton to run the method representedObject. Make sure you distinguish between a Class an an object or instance of that class.
You need to take the actual button, get its button cell, (at least I think that's what you want), and then call representedObject on the cell. If I am understanding you correctly. I never touch interface builder, so here's completely made up code that lines up with what you are asking for.
someObject = [[theButton cell] representedObject];
In addition to CH Buckingham's answer, you should also consider using bindings. You can bind the checkbox's value binding to the collection view item with a model key path which goes through representedObject to some property on your CardModel. (If desired, the key path can keep going through your model object graph.) That will set that property whenever the button is toggled.
I have read some questions and I find some very confusing and I don't really know if they answer my question.
I have an NSCollectionView implemented and connected to a Core Data context, everything shows correctly.
Now what I have is buttons in the view prototype, and when I click this buttons I need to get the value of the representedObject of that cloned view.
I have read and read and some parts are confusing to me, so I'm looking for a simple explanation.
Thank you for your time.
An action method takes one argument:
- (IBAction) collectionViewButtonClicked:(id)sender {
}
That sender is the control or other UI element (e.g., menu item) that sent the message.
With that argument, when your action method gets called, you know which button was clicked.
A button is a kind of control, and every control is backed by at least one cell. Cells have represented objects, too.
So, first, set the represented object of your button's cell to the collection view item that owns the button. (You can do this in the nib editor.) Then, in your action method, get the button's cell, then the cell's represented object (which is the item), then the item's represented object.
If the representedObject outlet doesn't show up in the nib editor, you probably have the button selected, not its cell. I recommend opening the nib editor's outline view using the button in the lower-left and then never, ever closing it.
I have an NSWindow which contains an NSImageView. This window gets activated everytime I click on a cell in my tableview. I only want 1 instance of the NSWindow to appear, but want to be able to change the contents of NSImageView.
How can I initialize NSWindow and display only 1 instance of it?
This is a job for a singleton!
http://developer.apple.com/documentation/Cocoa/Conceptual/CocoaFundamentals/CocoaObjects/CocoaObjects.html#//apple_ref/doc/uid/TP40002974-CH4-SW32
One possibility to do this is to create an NSWindowController subclass and an associated window XIB that gets loaded when the window controller is instantiated.
I'm sure you already have some controller class handling the mouse click in the NSTableView. In that class, simply keep around an instance of the NSWindowController subclass mentioned above as an instance variable. Whenever you need to display the window, tell that ivar to display its window.
If the window's contents are dependent on the clicked table cell, simply add some methods to the window controller that modify its window's contents and call these methods in your click-handling method before you display the window.
btw: I wouldn't use a singleton here because in this case it would just be a workaround for bad design (just my opinion, not a hard fact).