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.
Related
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.
So if I have an NSView based tableview and inside the views are NSTextViews which are non-editable but selectable...
how can I get that nice functionality of command-A selects all the text? I don't mean row selection. I have row selection disabled for the tableview. I mean highlighting the text in blue so you can copy it to your clipboard. But not just 1 NSTextView's text from one row, all of them from all the rows.
And in addition to command-A click and drag should do this too. But out of the box it seems I can only select one row's text. Here is video showing problem:
https://dl.dropboxusercontent.com/u/2510380/table.mov
(i keep clicking and dragging but can't highlight text on the next row)
here are two mac apps (skype and gabble) that do this:
https://dl.dropboxusercontent.com/u/2510380/skype.mov
and
https://dl.dropboxusercontent.com/u/2510380/gabble.mov
Assuming they are NOT using WebViews with just HTML inside, how do you get this control over the clipboard? i.e. in Skype you select the text and only the conversation is highlighted, not the timestamp of each message. Also the text copied to the clipboard is formatted very nicely. Can you point me in the right direction to reverse engineer skype?
Unfortunately there's no way to do this easily. This is because only ONE control can be the first responder at a time. This means that, though you can have selection in multiple text views, there are several problems:
Only one text view's text will actually be highlighted with the "live" highlight color; the others will have the gray highlight of non-focused controls.
Copy commands will only apply to the first responder text view.
Drag session starts will be initiated from the control the mouse was actually pointing at (irrespective of first responder) and will only drag that control's text.
In a view-based table view, the controls may not even "exist" for a row not currently displayed, so it'll never get the message unless you forcibly create each row, which could be costly for a large table.
Knowing all this, you might be able to "fake it" by having your controller be complicit in a text view and table view subclass's special handling of a select-all message when it's first responder. On receiving this message, the text view subclass can call super then notify the controller (to get its default behavior AND to let you know it happened), at which point the controller can turn around and send the command to all (existing) text views. Highlighting can be spoofed by overriding the text view's drawing and a drag initiation could defer to a delegate (the controller), which would handle writing ALL the strings from your model to the pasteboard (not even touching the text views in possibly-nonexistent row views). The table view subclass would simply pass the same select-all message to the controller without calling super (and even forcibly making sure nothing is selected before returning for good measure).
I hope this helps. If I've forgotten any of your requirements, let me know.
Try like this:-
First create button programatically then write this code after you create button and also write this code in your load method or awakefromnib method.
NSButton *Buttn=// alloc initwithframe;
[Buttn setKeyEquivalentModifierMask:
NSCommandKeyMask];
[Buttn setKeyEquivalent:#"A"];
[Buttn
setAction:#selector(yourmeth:)];
[Buttn setTarget:self];
// now when you press cmd a write
below code in action method
- (void)selectRowIndexes:(NSIndexSet
*)indexes byExtendingSelection:
(BOOL)extend
I have an NSPanel with a NSOutlineView to display my data. I want to select a row with a first click inside the NSOutlineView even if the panel is not in focus (i.e. not the key window) I have a delegate that allows selection and I have overridden the NSOutlineView class to override the acceptsFirstMouse: method, but I could not get the first click selection.
I checked the mouseDown event and it fired without any problems (in my class that overrides) when the panel was and wasn't the key window. But when the panel is not key, NSOutlineViewDelegate method shouldSelectItem: is not called.
What am I missing/doing wrong?
You just need to subclass your NSTableOutlineView and override:
- (BOOL)needsPanelToBecomeKey
to return NO.
NSView class reference states:
Overridden by subclasses to determine if the receiver requires its
panel, which might otherwise avoid becoming key, to become the key
window so that it can handle keyboard input and navigation.
Discussion
Such a subclass should also override acceptsFirstResponder
to return YES.
This method is also used in keyboard navigation. It determines if a
mouse click should give focus to a view (make it first responder).
Some views will want to get keyboard focus when you click in them, for
example text fields. Other views should only get focus if you tab to
them, for example, buttons. You wouldn't want focus to shift from a
textfield that has editing in progress simply because you clicked on a
check box.
Source: Apple documentation
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.
My Setup
I have a ViewController, where users type some sort of text in there. Call it InputViewController.
I have a UIView (in a separate class), where I draw a navigation bar that has a gradient (I override drawRect for Core Graphics, hence I need to to have in a separate class) which has a button. The button takes you to a MapViewController, which allows you to add a location tag to your input. Once a location tag is added, I would like to change the button's image.
My Problem
Once the button is tapped, I need to send the user's input to the MapViewController, where a delegate is also implemented and will pass back some information back to the InputViewController. The issue here is that the button resides in the separate UIView. One way to do this is pass the UIView the information once they are set, which in turn would be passed to the MapViewController once the button is tapped. The problem here would be the delegate as the delegate needs to return to the InputViewController and not the `UIView.
I was wondering if its possible to move the UIView into the InputViewController, including the drawRect method for that view. If so, how can I do that? If not, what are other ways/suggestions I can do to have the above set up?
I guess you need to use NSNotifications for sending messages to your classes. See this.