I just started working on an OSX application, first time in objective-c. I need to make a window that will display all the network interfaces available on the computer.
So far
I have an AppDelegate that pretty much does nothing
I have set the Main nib file base name to my main window, which is a xib, header and implementation file
I made my xib window inherit from my class and added the outlets I needed using right-click drag (worked well, I assumed I was correct until then)
The issue
I can't seem either override or bind the load event of the window, where I want to load the text in my label.
I've seen some people use a NSWindowController, but I don't think I need this.
My question
Is it required to have a NSWindowController PLUS a NSWindow class? I feel there are too many files for a single window. I have the xib and two .h/.m files... If it's not required, how can I get notified when the window loads?
The question wether you need NSWindowController(s) or not depends on the complexity of your application.
If your app is only a small utility using a single window, you might get away with setting up your UI in MainMenu.xib and connect it to some IBOutlets in your AppDelegate.
But the above approach gets messy soon when your app becomes more complex. To tame that complexity, you can create dedicated NSWindowController classes (e.g. one per window). Those window controllers could manage a hierarchy of child NSViewControllers to further split up your complexity.
If it's not required, how can I get notified when the window loads?
The default Xcode template should have created an AppDelegate.m file. You can add code to initialize your UI in
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
At this point the window has been fully loaded and
#property (weak) IBOutlet NSWindow *window;
should point to your window instance.
I'm trying to extend the NameAndPassword code sample so that the secure text fields run authentication action on return key press (currently the authentication only works if the button is pressed through the buttonPressed action).
I tried various options - creating a xib file along with ViewController to replace the existing nib file, but in such case I can't create a connection between the xib custom view and the IBOutlet that was connected to the view in the nib file before I removed it.
I also tried connecting the existing secure password field from the nib file to an App Delegate I created myself, but it doesn't want to work either - I control-drag the textfield to the appdelegate.h interface section but no lines show up.
I know this sample is very outdated now - my question is, how can I create custom actions on these views or how to recreate this project on a fresh surface?
IIRC you can't connect target-action on custom views. It only works with Apple-provided views and subclasses thereof (so if your view was a subclass of NSControl, it would work). However, you can always call setTarget: and setAction on your view in the awakeFromNib (or equivalent) method of whatever object owns the NIB.
If your class is already a subclass of another Apple-class that supports target/action, there is probably a syntax error somewhere in your code, or an #if/#ifdef or the like that makes the Interface Builder part of Xcode unable to correctly parse your class. In that case it often leaves it out, and you get none of its IBOutlets listed.
I am playing around with the default XCode template for a cocoa application. By default it has a MainMenu.xib with a window and a menu -- awesome.
I intend to build up my views/subviews in code, so I then create a RootView : NSView and a RootViewController : NSViewController, and bind them up in IB so that my base view in that window is my RootView, controlled by my RootViewController.
Enter my question -- How do I do the same to have a RootWindowController bound to the NSWindow? I had assumed File Owner was the trick, but it's set to NSApplication, which I think is correct. The main goal of NSWindowController in my case is to manage the toolbar based on NSNotifications fired from other services -- is this even the correct design here? I don't think I can do this from my RootViewController since I don't have a window reference, but is that where I should do it instead?
Many times, the application delegate is used as the main/central controller for a non-document-based application. This is a good place. This can be an NSWindowController instance if you like. You can just do away with the existing window in your nib.
Helpful information from the NSWindowController API reference:
You should create a subclass of NSWindowController when you want to augment the default behavior, such as to give the window a custom title or to perform some setup tasks before the window is loaded. In your class’s initialization method, be sure to invoke on super either one of the initWithWindowNibName:... initializers or the initWithWindow: initializer. Which one depends on whether the window object originates in a nib file or is programmatically created.
But if it were me, I wouldn't bother going the NSWindowController route; I'd just add this logic to my app controller (and set it as the app delegate) since this is app-level stuff. No need to add a layer of complexity unless you've got a LOT of main-UI-updating complexity you want to compartmentalize.
When you create a new application in Xcode, it automatically creates a AppDelegate and a MainMenu.xib. The latter also contains the application main window, which is linked to the AppDelegate as an IBOutlet.
What I tried to do is, use a MainWindow from a different xib-file. However, there's absolutely nothing I can do to prevent Cocoa from showing the first window it created in the first place, even if I remove the IBOutlet link and comment it out in the source file and what not...
Hope someone can explain this, as it has been bugging me for a while now...
Whether or not a window in a XIB is shown at launch is not controlled by an explicit code, but instead controlled by the state of the window "freeze-dried" in the XIB.
More concretely, in an inspector of an NSWindow in the Interface Builder, you have the option called Visible at launch under the heading Behavior.
When the Cocoa system loads a nib and encounters a window with this bit on, it just shows it on the screen. It's independent of whether you have IBOutlet or not. You see, it's also the Cocoa system which sets UI objects to IBOutlets when it loads a nib... it can do whatever it wants.
Here's a simplification:
I have an application with several buttons. If it is the first time the application is launching, I want to do some special things. In my AppController class, which is a delegate of NSApp, I use the delegate method -applicationDidFinishLaunching: to perform the test. After I've detected that it is the first time, I first want to access some IBOutlets. Then, I'd like to be able to get mouse events for each button, so that I can do other things.
I can't figure out want to do with the classes. I'd like to make a new class (FirstLaunch) for the first launch, but I'm not sure what to call from AppDelegate. Also, to get mouse events, shouldn't I be a sublass of the buttons, and considering that I have multiple buttons, I'm confused. I could probably tackle these issues one-by-one, but taken all together, they're confusing me.
Broken down, I need to access & manipulate IBOutlets I have set in IB, determine when buttons are clicked (and which button was clicked). I'd like to be able to do this from another class so as to not clutter up the AppDelegate.
Thanks for the help!
To be more clear, what I'm actually trying to do is to use Matt Gemmel's MAAttachedWindow to put up a help bubble by a button. When the button is clicked clicked, the bubble disappears and another one is put somewhere else. The bubbles will be attached to controls in the main window.
I'm guessing you want to show some additional user interface on the first launch? If it's a separate window, I'd advise creating a subclass of NSWindowController. Add a new NIB file for the first-run user interface to your project and change the class of the File's Owner object to FirstLaunch. Control-drag a wire from the File's Owner delegate onto the window to connect it with the window outlet.
You create IBOutlets by adding an instance variable to the class. If your app will only run on Leopard or higher, it's better to declare your outlets like this:
#interface FirstLaunch : NSWindowController {
NSTextField *myTextField;
}
#property (nonatomic, retain) IBOutlet NSTextField *myTextField;
#end
In Interface Builder, you'll control-drag a wire from the File's Owner onto the control to associate it with that outlet. Make sure that you release your reference to each IBOutlet in your class's dealloc method (if you're not using garbage collection) or else your app will leak memory.
Buttons send action messages when they're clicked, so you'll need to provide an action method for the button to call. You do that by declaring a method with a signature like this:
- (IBAction)myButtonClicked:(id)sender;
In Interface Builder, you'll control-drag a wire from the button onto your window controller and choose the myButtonClicked: method.
To make all this work, you'll need to create an instance of the window controller and tell it to load the NIB file at runtime. So, in your AppDelegate class, when you've determined that this is the first launch, you'll do this:
FirstLaunch *firstLaunchController = [[FirstLaunch alloc] initWithWindowNibName:#"nameOfNibFile"];
[firstLaunchController show:self];
You'll probably want to keep the reference to the window controller in an instance variable instead of a local variable like I've done here. And, depending on your application, it may make more sense to show this as a sheet. But once you've made it this far, you'll be able to figure out how to do that on your own.
Then, I'd like to be able to get mouse events for each button, so that I can do other things.
Don't worry about the mouse. There may not even be a mouse (think of the ever-popular tablet-Mac rumor).
I'd like to make a new class (FirstLaunch) for the first launch, but I'm not sure what to call from AppDelegate.
You make your own methods here. You'll probably make it a singleton*; then, you'll implement a method named something like runFirstLaunchPanel:, which will be an action method (more on those in a moment):
- (IBAction) runFirstLaunchPanel:(id)sender;
Instantiate the object in the nib, then, from your app delegate, call the action method with nil as the sender.
The reason to put the object in your nib and make the method an action method is that this makes it easy to hook up a menu item to it, so that the user can re-run the first-launch panel at a later time. (For example, if it's a Starting Points window, you might connect the New menu item to this action instead of the default one.)
*Yes, I've seen the articles about singletons, and I agree with them. In a case like this, it's OK.
Also, to get mouse events,
This is the wrong way of thinking about it. What you need to do is set your button up to send a message to your controller to make the controller (probably AppDelegate) do something. The message you want the button to send is an action message.
Implement an action method in the object that owns the nib containing the window with the buttons. Declare this method in the class's header, then connect the button to it in IB by right-clicking on your controller and dragging from the correct action method's circle to the button.
This is called the target-action paradigm, and it insulates controller responsibilities (doing things) from the views that ordered them. Because each action method does only one thing, you can have a button, a menu item, and even another controller (your app delegate, above) send the same action message, and the receiving controller won't have to care which control is sending the action, because it already knows what it has to do.
shouldn't I be a sublass of the buttons,
No. You very rarely create subclasses of anything other than NSObject (or, for model objects in Core Data, NSManagedObject) in Cocoa.
Note that I said “rarely”, not “never”. You will have to make the occasional subclass, especially if you want to create custom or customized views and cells (and, maybe, customized windows). However, subclassing is not necessary in Cocoa to the degree that (I hear) it is in some other frameworks on other platforms.
and considering that I have multiple buttons, I'm confused.
The target-action paradigm means you don't have to create one button subclass per button. One controller class implements all the actions, and the stock buttons, because you've hooked them up in IB, simply tell the controller “do this”.
Broken down, I need to access & manipulate IBOutlets I have set in IB,
Probably not. At least, not as much as you think you do.
determine when buttons are clicked (and which button was clicked).
Nope. The buttons will worry about being clicked; you just worry about setting them up to send, and then responding to, their action messages.