I'm trying to build a To-do list application. I have 2 tablesviews and one textfield. In the first tableview are the different projects, and when you click on one of them the associated todos appear in the second tableview. It's a pretty basic Master-detail I guess.
I set it all up with bindings.
Right now the way you add a task, is you click on an add button and it adds a row with a placeholder text that's editable.
But what I want, is the user to enter the task in the textfield, press add, and then it adds the todo with the name already set.
So basically I have TodoItem Class with a name property, and my question would be, how do I get the content of the nstextfield and assign it to the name property ?
I tried creating an outlet from the Todoitem class to the textfield, but xcode won't let me connect it....
Tell me if you need to see any code, but since I used bindings, there's almost nothing to show. Thanks!
… how do I get the content of the nstextfield and assign it to the name property ?
Translate that directly into Objective-C:
NSString *contentOfTheNSTextField = [myTextField stringValue];
myNewTask.name = contentOfTheNSTextField;
You'd do that in the action method that you've set both the button and the field to call.
I tried creating an outlet from the Todoitem class to the textfield, but xcode won't let me connect it....
To do this, the Todoitem would need to reside in the nib.
But, even if you could do that, why should the model object know about the text field? Carrying values between model and view is a controller's job.
Related
I have a button that is inside a view repeated inside a NSCollectionView. I can bind the title of the button to one of the properties in my model class but I want to wire the selector of the button to one of the selectors in my model class. Obviously, the button must send the message to the model object associated with the corresponding collection view item.
I managed to bind the target for the button but how to set the selector? I want to do that in Interface Builder if possible...
I figured it out. In the Ib there is a selector textbox bellow the path textbox where I bind the target. I don't know why I didn't see it. I spent nearly one hour trying to solve this issue.
How to add those blindings? I still can't find it.
I find it . It's Here.
BACKGROUND:
I have a tableview with a list of names. When you click on a name in the list, it displays additional detail information in another section of the window. Everything is connected and is working correctly.
However...
I would like to use Type Select with this table and have run into the following snag:
When I start typing a name (while the table is selected) it correctly highlights the appropriate name in the table BUT the detailed information to the right of the table does not change.
I know the reason is the code for changing the detail information is in an IBAction method which is only called when you click to select a name in the list, and uses the [sender clickedRow] call to get the index of the selected name.
I also suspect that I need to use the [tableView selectedRow] (since it is being selected, but you are not clicking on it) but I am not quite certain where or how to perform this check.
I'm also thinking that since "type select" isn't sending an action message, I won't be able to use [sender selectedRow] but rather will use [tableView selectedRow]...
QUESTION:
How can I tell when the selected row in a tableview has changed via type select?
Thanks!
Implement the tableViewSelectionDidChange: delegate method in your controller, and ensure that your controller is the NSTableView's delegate.
You could update your view with something like:
- (void)tableViewSelectionDidChange:(NSNotification *)aNotification {
[relatedView updateInformationFromRow:[[aNotification object] selectedRow]];
}
From the documentation:
tableViewSelectionDidChange: Informs the delegate that the table
view’s selection has changed.
Within that, you would update your related view. You could use the aNotification's object, which will be a NSTableViewSelectionDidChangeNotification, again from the documentation, is:
Posted after an NSTableView object's selection changes. The
notification object is the table view whose selection changed. This
notification does not contain a userInfo dictionary.
I've developed an app for Mac OS X Lion using its new view-based NSTableView, but as I want to port the whole app to Snow Leopard I'm trying to figure out the best way to emulate such a tableview. So far I've created a NSCollectionView and everything is fine, except for the fact that I can't get the index of the view from which a button click event is triggered.
In Lion I have the following function:
- (IBAction)buttonClick:(id)sender
so I can get the index of the view inside the tableview using a method (I can't remember its name) like
- (NSInteger)rowForView:(NSView *)aView
with aView being the sender's superview, but I couldn't find something similar for the collection view ... The only "useful" method seems to be
- (NSCollectionViewItem *)itemAtIndex:(NSUInteger)index
(or something like this), but this can't help me as it returns a NSCollectionViewItem and I can't even access it knowing only the corresponding view!
Within buttonClick, try this code:
id collectionViewItem = [sender superview];
NSInteger index = [[collectionView subviews] indexOfObject:collectionViewItem];
return index;
Hope this helps :)
Geesh! Both of those approaches have issues. I can see how the first on may work, but note that the "collectionViewItem" is actually the view, NOT the collectionViewItem, which is a view controller.
The second way will not work, unless you subclass the button and put in a back link to the collectionViewItem. Otherwise, your view does not know what collectionViewItem controls it. You should use a selector binding to the collectionViewItem's representedObject instead, to get the action to the correct object in your array.
How about something like:
id obj = [collectonViewItem representedObject];
NSInteger index = [[collectionView contents] indexOfObject:obj];
As I suggested here: How to handle a button click from NSCollectionView
I would do it like this (because the button you want to press should be coupled with the corresponding model, therefore the represented object):
Add a method to the model of your collectionViewItem (e.g. buttonClicked)
Bind the Button Target to Collection View Item
While binding set model key path to: representedObject
While binding set selectorname to: methodname you chose earlier (e.g. buttonClicked)
Add protocol to your model, if you must tell delegate or establish observer-pattern
use NSArrayController for binding to NSCollectionView,
use collectonViewItem.representedObject to get a Custom Model defined by yourself.
save and get index in your custom model.
That's works for me.
After I drag a controller object to the document window, how do I give it a Boolean property?
Assuming you want the ability to expose and edit the property values of your custom controller as attributes showing up in IB's inspector, you'll need to write your own plugin which tells IB what the inspector should look like. This really can't be answered briefly.
Here's Apple's reference on IB Plugins:
http://developer.apple.com/mac/library/documentation/DeveloperTools/Conceptual/IBPlugInGuide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40004323-CH1-SW1
And here's the inspector portion:
http://developer.apple.com/mac/library/documentation/DeveloperTools/Conceptual/IBPlugInGuide/CreatingInspectors/CreatingInspectors.html#//apple_ref/doc/uid/TP40004323-CH6-SW1
If you truly just want to add a property to the controller's interface, you do this in Xcode (modifying the interface and implementation accordingly) and IB will pick up the changes automagically.
In the case of a checkbox, the checkbox itself is either checked or not. That state stores the boolean value instead of the controller (unless you wish it.)
To have the app undertake an action upon clicking it, think of it as a button instead of a data display and link it to an action method in the view controller. That's the simplest and old school way of doing it.
To use binding, you need to bind the checkbox's value attribute to a controller. Usually for binary values its an object controller. So, in IB, drag an Object controller to your nib window and bind it to your data source. Then, drag a checkmark button to the interface. In the checkmarks binding inspector. Set "value" binding to the name of the object controller, controller key to selection, keypath to the name of the data source attribute and provide a value transformer if needed.
(Abstract: bindings work in code, but not in IB)
I have a window managed by a NSWindowController. To the left of the window is a source view. To the right is a table view showing the elements of the currently selected source.
I have set up a NSTreeController within my window XIB. I want its contents to be used for the source view. It's selection will drive the table view.
I am trying to split this up using NSViewControllers. One view controller will load a NIB containing the source view. Another view controller will load the table view.
Seeing that I need access to the NSTreeController within the source view controller, I have set it to be the view controller's representedObject. (Actually for this setup to be done by the time awakeFromNib is called on the view controller, I have turned representedObject into an IBOutlet).
All works fine when I wire my source view up in code:
[outlineView bind:#"content"
toObject:sources
withKeyPath:#"arrangedObjects"
options:nil];
[outlineView bind:#"selectionIndexPaths"
toObject:sources
withKeyPath:#"selectionIndexPaths"
options:nil];
[[outlineView tableColumnWithIdentifier:#"Title"] bind:#"value"
toObject:sources
withKeyPath:#"arrangedObjects.title"
options:nil];
I am however unable to reproduce this using Interface Builder. Thing is, here the "controller key" textfield is grayed out. Thus I bind column's "value" to the file owner using a model keyPath of "representedObject.arrangedObjects.title". This does not show the desired behavior. Actually an exception is thrown: -[NSProxy doesNotRecognizeSelector:_mutatingNodes] called!
How can I use representedObject in IB?
Can I create a controller in IB which acts as proxy to representedObject?
Could I set-up a tree controller in the source view XIB which during NIB loading gets swapped out for the representedObject?
I moved away from using representedObject. It appears that is meant only for model objects.
I now pass in my tree controller using a custom outlet. I continued setting up and tearing down the bindings in code.
I’ve similar issues when I try to pass a reference to an object controller (NSTreeController in my case). I don’t think this is how Apple wants you to use their KVO-compatible controllers. The exceptions look like they’re XIB-unarchiving & timing-related.
The trick is not to pass the controllers, but to pass the underlying data and keep the selection in sync.
This way you can set up your bindings in a storyboard and won’t get any exceptions. You’ll have to set up a new instance of an object controller for every child view controller (copy & paste in Storyboard once you configured the first one works). For a detailed example take a look at another answer that gets much more into detail.