How do I set an action for when a user double clicks an NSCollectionViewItem. NSTableView, for example, has the setDoubleAction method. Is there something similar for NSCollectionView?
Thanks
I know this question is ancient, but it comes up as the third result on Google right now, and I've found a different and very straightforward method that I haven't seen documented elsewhere. (I don't just need to manipulate the represented item, but have more complex work to do in my app.)
NSCollectionView inherits from NSView, so you can simply create a custom subclass and override mouseDown. This is not completely without pitfalls - you need to check the click count, and convert the point from the main window to your collection view's coordinate, before using NSCollectionView's indexPathForItem method:
override func mouseDown(with theEvent: NSEvent) {
if theEvent.clickCount == 2 {
let locationInWindow = theEvent.locationInWindow
let locationInView = convert(locationInWindow, from: NSApplication.shared.mainWindow?.contentView)
if let doubleClickedItem = indexPathForItem(at: locationInView){
// handle double click - I've created a DoubleClickDelegate
// (my collectionView's delegate, but you could use notifications as well)
...
This feels as if I've finally found the method Apple intended to be used - otherwise, there's no reason for indexPathForItem(at:) to exist.
You'd probably want to handle this in your NSCollectionViewItem, rather than the NSCollectionView itself (to work off your NSTableView analogy).
Related
[Edit] as Willeke helpfully points out it's menuDidClose: NOT menuWillClose:. My code actually had that part right. Correcting the post in case someone else finds this researching a similar problem.
I'm sure this is just a Cocoa newbie problem but I've wracked my brain on it for hours. I've read the NSMenu and NSMenuDelegate docs a few times trying to figure out what I'm missing but it looks straight forward.
I have a window controller for a preferences window with a toolbar and three views. The window controller is declared as NSMenuDelegate.
#interface PrefsController : NSWindowController <NSMenuDelegate, NSWindowDelegate, NSOpenSavePanelDelegate>
This issue is a NSPopUpButton on the first view. The menu associated with popupbutton works fine. I can modify, etc. the menu via the associated IBOutlet variable. It's bound to Shared User Defaults Controller for selected value and that works fine.
But the menuWillOpen: and menuDidClose: methods are not invoked when the menu is accessed.
- (void)menuWillOpen:(NSMenu *)menu {
if (menu == myPopupButton.menu) {
[self updateMenuImages:NSMakeSize(32, 32)];
}
}
- (void)menuDidClose:(NSMenu *)menu {
if (menu == myPopupButton.menu) {
[self updateMenuImages:NSMakeSize(16, 16)];
}
}
My apologies for what is almost certainly a dumb mistake on my part, but I'm stumped.
Menu delegates are not used that often, so Apple hasn't made them too easy to set up in Interface Builder. Instead, do this in awakeFromNib:
myPopupButton.menu.delegate = self;
I’m using a regular (not subclassed) NSTableCellView in a view-based table view. It has the initial image and text field views. I added an NSStepper to the view.
The text field is bound to tableCellView.objectValue.quantity.
The stepper’s value is bound to tableCellView.objectValue.quantity too.
The problem is that when running the app, when I click the stepper it doesn’t seem to get the mouse event, neither arrow gets highlighted, the value is not incremented or decremented.
If I set the double action of the table view it gets triggered if I double-click the stepper as if it was transparent.
What am I missing?
Thanks!
You should look at the documentation but easiest is that you need to subclass NSTableView and override this method to validate the proposed first responder. As the document states NSTableViews disallow some controls to be used unless the row is first selected. Even then it still may discard some.
- (BOOL)validateProposedFirstResponder:(NSResponder *)responder forEvent:(NSEvent *)event {
return YES;
}
Further to the correct answer from Robert Payne, with Swift you could add an extension to NSTableView and not subclass it.
extension NSTableView {
override public func validateProposedFirstResponder(responder: NSResponder, forEvent event: NSEvent?) -> Bool {
return true
}
}
And I'd like to emphasis that it's the NSTableView not the NSTableViewCell.
UPDATED: I'm now overriding the NSView keyUp method from a NSView subclass set to first responder like below, but am still not seeing evidence that it is being called.
#implementation svsView
- (BOOL)acceptsFirstResponder {
return YES;
}
- (void)keyUp:(NSEvent *)event {
//--do key up stuff--
NSLog(#"key up'd!");
}
#end
--ORIGINAL POST--
I'm new to Cocoa and Obj-C and am trying to do a (void)keyUp: from within the implementation of my controller class (which itself is of type NSController). I'm not sure if this is the right place to put it, though. I have a series of like buttons each set to a unique key equivalent (IB button attribute) and each calls my (IBAction)keyInput method which then passes the identity of each key onto another object. This runs just fine, but I also want to track when each key is released.
--ORIGINAL [bad] EXAMPLE--
#implementation svsController
//init
//IBActions
- (IBAction)keyInput:(id)sender {
//--do key down stuff--
}
- (void)keyUp:(NSEvent *)event {
//--do key up stuff--
}
#end
Upon fail, I also tried the keyUp as an IBAction (instead of void), like the user-defined keyInput is, and hooked it up to the appropriate buttons in Interface Builder, but then keyUp was only called when the keys were down and not when released. (Which I kind of figured would happen.)
Pardon my noobery, but should I be putting this method in another class or doing something differently? Wherever it is, though, I need it be able to access objects owned by the controller class.
Thanks for any insight you may have.
NSResponder subclasses (such as a custom subclass of NSView) handle key events. They even handle more abstract-level events such as "move left/right", "insert newline", etc. They can then send a message to a controller to respond accordingly.
Wow! I think I've nailed it. I just needed to instantiate my subclass with a NSView/NSWindow reference to the class in IB. Wasn't actually creating an instance of it in the UI. The past several hours down the crapper! Sans that I learned a thing or two along the way. ;)
I'm trying to create a file explorer using nscollectionview and am currently implementing a right click menu for each item (i.e. copy/delete/rename/etc). I currently have:
An NSCollectionView linked with an NSArrayController which holds a custom object
A subclass of NSBox as the view for each item, this also tracks mouse events and passes them to the controller
The controller has an NSMenu outlet (rcMenu) and also an NSView outlet (itemView) for the NSBox subclass that should be where the menu popup
The code for calling the menu is:
[NSMenu popUpContextMenu:rcMenu withEvent:event forView:itemView];
Once run, this works in that the menu pops up when right clicking the item in the collection view, but on inspecting the event that's passed to the controller, there's not really anything I could use to find out which item was right clicked other than the x,y coordinates (which seem to be for the NSWindow rather than the item or NSCollectionView). What I really want is the object in the NSArrayController that had it's view right clicked.
Is this down to me setting it up incorrectly, is there an easy way to figure it out, or is it just that tough to work it out?
You might try setting the menu of each collection view item's view. Most likely, you'll do this by overriding +defaultMenu in your item view class. Once you do that, comment out the popUpContextMenu:withEvent:forView: message and see whether you can get away without it.
Furthermore, it would then not be too hard to serve up different menus for different kinds of items (e.g., folders vs. packages vs. files, and different types of files at that). You'd probably have to override -menuForEvent: instead of +defaultMenu.
I found an other solution that might help.
For this solution I made a subclass of NSCollectionViewItem and NSView, respectively (and for the ease of explaining) ItemViewController and ItemView.
I'm assuming you work with IB where you have already bound your NSCollectionView to the ContentArray of your NSArrayController (also bind the selectionIndexes).
Next add an ViewController object to the NIB and make sure its custom class is set to the ItemViewController. Now connect it to the itemPrototype outlet of your NSCollectionView.
Next add a Custom View object to the NIB and set its custom class to ItemView. Connect its outlet to the view property of your ItemViewController.
In the interface file of ItemView create a representedObject-like property. With this I mean something like:
#property (nonatomic, assign) id someRepresentedObjectPropertyName
This will be the property which will represent the item in your NSArrayController.
Now go to the implementation file of ItemViewController and override the -setRepresentedObject: method. In here we will first let the ItemViewController handle setting its representedObject, afterwards we assign the same representedObject to the property we made in ItemView. The override would look like:
-(void)setRepresentedObject:(id)representedObject {
[super setRepresentedObject:representedObject];
//Do some appropiate checking on the representedObject...
if (self.view != nil) {
[(ItemView *)self.view setSomeRepresentedObjectPropertyName:self.representedObject];
}
}
Now if you go back to the implementation of ItemView you can override the method -rightMouseUp: and build/set-up a NSMenu there and use the -popUpMenuPositioning...: method. The someRepresentedObjectPropertyName property of ItemView should be set to the correct item in your NSArrayController.
EDIT:
Instead of overriding -setRepresentedObject you could also bind the ItemView's someRepresentedObjectPropertyName to representedObject.someRepresentedObjectPropertyName
It's easy enough to set up a table view to allow editing. Just add one line to your UITableViewController:
self.navigationItem.rightBarButtonItem = self.editButtonItem;
This line adds an edit button on the nav bar that will change the table to editing mode and change its button text to "Done" while editing.
Is it possible to set this up in Interface Builder? I see that you can add a UIBarButtonItem and can set its "Identifier" to "Edit", but I don't see the expected behavior.
BTW, what does the "Identifier" in the Attributes panel do?
Yes, you can add UIBarButtonItems in Interface Builder, and they should work.
The identifier lets you use a preset button (like Edit or Reload), or you can choose Custom and make your own button.
EDIT: I may be able to help further if you could explain how UIBarButtonItems added through IB don't work.
UPDATE: UIViewController.editButtonItem is a special method that returns a UIBarButtonItem that invokes the view's setEditing method. You can achieve the same effect by creating a method that does the same thing and connecting the selector to your UIBarButtonItem in IB.
In your header file:
- IBAction edit:(id)sender;
and in your implementation file:
- (IBAction) edit:(id)sender {
[self setEditing:YES animated:YES];
}
then connect the selector to the UIBarButtonItem.
However, you might not be able to create this connection in the default Navigation-Based Application template since the Table View is in a separate file.
Have a look here: http://blog.tmro.net/2009/05/uitabbarbuttonitem-did-not-change-its.html
If you want your button to be able to change its label dynamically make sure you use a custom identifier otherwise its title will be immutable.
We still can't seem to do this specifically in Interface Builder as of Xcode 9.4.1. It's very easy to do in code, though.
You don't need to set up the button in IB at all. Simply add this code in your viewDidLoad method:
navigationItem.leftBarButtonItem = editButtonItem
That automatically sets up the Edit button, which turns to Done so the user can end editing.
To do anything custom associated with the editing process, override the view controller's setEditing(_ editing: Bool, animated: Bool) method.
For example, if you have a table view whose editing needs to be turned on and off, you can do this:
override func setEditing(_ editing: Bool, animated: Bool) {
super.setEditing(editing, animated: animated)
tableView.setEditing(editing, animated: animated)
}
Make sure to call super.setEditing here.
Note: if you're using a UITableViewController, setEditing is already set up in the super class to handle the table view. You don't need to override it, unless you have other custom code you want to include when editing is enabled/disabled.