I'm following Apple's tutorial on adding a custom UIView sublcass to Interface Builder. They tell me to first label my UIView subclass. I have done that:
#import <UIKit/UIKit.h>
IB_DESIGNABLE
#interface LoggedOutView : UIView
#end
Then they tell me to drag that UIView subclass from the Object Library in Interface Builder. I don't know where exactly is the Object Library. I am guessing it is the box in the lower right of the screen that shows all the standard UIViews. I search for my class in all 4 sections of that box and cannot find it.
Keep in mind that this is the first time I've ever used Interface Builder. I usually code all my UIView subclasses. However, I was forced to create a XIB for iOS 8's dynamic launch screens. (At least I think XIB's are required to flexibly layout launch screens on iOS 8).
Quick answer: you don't.
The launch screen does not load any code at all. It is merely a nib file that allows you to use auto layout to layout views on a screen. You can use text in labels, images, etc...
It's there so you can create launch screens for all different sizes of device and they will all be laid out correctly by AutoLayout.
You can't run any code though. Just use a plain UIViewController and standard UI elements UILabel, UIImageView, etc...
Related
I have managed to get the IBDesignable/IBInspectable attributes working with direct subclasses of NSView but not with a direct subclass of NSButton. This is causing me to question if in fact the Cocoa implementation is somehow limited to NSView only.
Almost every example on the web (and Apple WWDC 2014 Xcode video) use NSView and then drag a custom view component from the library onto the canvas (and then change its class).
Is it possible to use IBDesignable with subclasses of NSControl and NSButton etc...? I have seen many examples on the web using UIButton.
If it is possible, then what are you supposed to drag from the library onto the canvas? It doesn't make sense for it to be a "custom view". On the other hand, there is no "custom control" available.
To be clear, I can get the IBInspectable attribute to show up at design time; but any changes don't seem to live render at design time.
The workaround is to wrap any custom NSButton I want to create within an NSView (via composition) but this seems like a bit of a hack...
I started playing around with a custom NSButton and NSButtonCell.
Dragging a button from the library onto the canvas and changing its class and the cell class doesn't live render. I think this is because Interface Builder still does a lot of custom things to setup NSButtonCell.
What works fine for me is dragging a custom view from the library onto the canvas and set its class. For this to work you need to setup the cell inside NSButtons -initWithCoder:.
Also I found a sample from Apple with a layer-backed custom Checkbox.
You need to drag an NSButton onto the view, then set the Custom Class to your specific NSButton descendant. Not sure why it doesn't work when you start with an NSView.
What can give you a hint is that the NSButton specific attributes aren't in the "Attributes Inspector". Hence there must be some setup at the time you drag the control onto the view.
I'm working on my first iPad application and using Storyboards for the first time.
I've got UITableViewController in my Storyboard that uses "Dynamic Prototypes" for custom cells.
What I want to do is programatically instantiate my UITableViewController subclasses but loading the super view controller from the Storyboard.
This is because I have a single UI but multiple subclasses for specific functionality that I need for each different instance.
This was very easy to do with .xib files, I would write the following code:
MyViewControllerSubClassA *viewControllerA = [[MyViewControllerSubClassA alloc] initWithNibName:#"generalViewControllerNib" bundle:nil];
MyViewControllerSubClassB *viewControllerB = [[MyViewControllerSubClassB alloc] initWithNibName:#"generalViewControllerNib" bundle:nil];
I know I can assign a subclass in the Storyboard editor when clicking on the View Controller but I want to set the subclass programmatically when instantiating.
This seems impossible to do with Storyboards as they are instantiated automatically.
This makes the entire concept of Storyboards seem flawed and not very OO.
If I move the View Controller out of the Storyboard and into a .xib file I lose the ability to use Dynamic & Static Prototypes cells as these are supported only when using Storyboards. Also Apple's documentation basically says use Storybaords from now on.
I would try something like this:
MyViewControllerSubclassA *controllerA = (MyViewControllerSubclassA *)[self.storyboard instantiateViewControllerWithIdentifier:#"myGenericVC"];
I still have a lot to learn with cocoa so I may have missed something obvious here. I have a custom view I would like to display in an nssplitview which replaces the current subview there.
I have a MessageView.xib file, and a MessageView .h/.m which subclasses NSView. I created a custom view instance for my main window (the one which contains the nssplitview) through Xcode 4's built in gui builder. I created an outlet to this instance of MessageView in my window's controller.
In my controller for the window when I want to swap out the subview for the splitview it runs this
[splitView replaceSubview:[[splitView subviews] objectAtIndex:1] with:viewMessage];
viewMessage is the outlet to the MessageView.
When this code is run the display of that subview changes to be blank. I'm not sure if there is something wrong with my custom view or there is some size issue. Is there something I need to do to fit the view into the split screen view or is my custom view just not displaying correctly? I have had a difficult time finding a tutorial on creating custom subviews with Xcode 4 so I'm not sure if something could be wrong with that. The custom view just has a label and a textfield in it.
Generally, you shouldn't need to replace NSSplitView's subviews with your own. Rather, you add your own custom view(s) as child views of the default subviews on each side of the divider. You can do this in code with addSubview:, but it's probably easier to just use Interface Builder in Xcode. Drag a "Custom View" into the splitview, then in the Identity Inspector, under Custom class, change the class to the name of your custom NSView subclass:
I think (off the top of my head, not tested), if you really do need to replace the default NSSplitView subviews with your own class, you can probably do it in Interface Builder using this same method, but selecting the default subview itself and changing its class in the inspector. This doesn't work for all AppKit classes, but it may work for NSSplitView.
I'm struggling with Cocoa for 2 hours now without success. I want to add a custom view to the toolbar. So, I added a NSToolbar to the window (with IB), and added my view (which works perfectly). IB automatically created a NSToolbarItem.
I followed the instructions from Apple here: http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/Toolbars/Tasks/AddRemoveToolbarItems.html#//apple_ref/doc/uid/20000755-BBCGJCDJ
The problem is that I don't know what to do now, the view doesn't show although it's label is displayed in the window.
Here's the code I use to draw (very simple, it's for testing purpose)
- (void)drawRect:(NSRect)dirtyRect {
[[NSColor blackColor] set];
[[NSBezierPath bezierPathWithRect:self.bounds] fill];
}
Can someone help me?
Thanks in advance.
I solved the problem.
I put my custom view in the root of the nib. I added a classic NSToolbarItem and created two outlets: one for the custom view and one for the NSToolbarItem. On -(void)awakeFromNib, I called setView: on the NSToolbarItem with the custom view.
According to some ressources on the internet, it is a bug with Interface Builder.
According to an Apple engineer in the discussion at http://www.mail-archive.com/cocoa-dev#lists.apple.com/msg35673.html, there is a bug in Interface Builder whereby "Custom Views" (NSViews created in IB) are not decoded properly when used as the view for an NSToolbarItem, and so do not appear in the toolbar. Other kinds of NSViews, such as NSButtons and NSBoxes, will work just fine as toolbar items: you can create these in Interface Builder and then drag them into the toolbar to make them into toolbar items.
(The discussion in the link above implies that the bug is down to how "Custom Views" are created from the XIB at runtime: using initWithFrame: instead of initWithCoder:. The discussion dates from 2009 but this still hasn't been fixed as of XCode 4.5/OS X 10.8.)
In my case I was using a regular NSView to wrap a set of controls (a volume slider and min/max buttons), rather than implementing a custom NSView subclass. I was able to avoid the problem by using an NSBox as the container instead of an NSView: I made the NSBox transparent, title-less and borderless, so it otherwise acted exactly like a plain NSView wrapper. This was a little more work in IB, but saved me the trouble of wiring up the view to the toolbar item programmatically.
Popovers are heavily used in iPad apps and I really like them. Now I think about how this could be implemented in AppKit on the mac because I have a use case for it.
Do I need a NSWindow subclass to accomplish the overlay or could I also use a normal view?
According to Apple's Developer Documentation, you can use built in popovers on OS X with the built-in NSPopover class:
Starting in OS X v10.7, AppKit provides support for popovers by way of the NSPopover class. A popover provides a means to display additional content related to existing content on the screen. The view containing the existing content—from which the popover arises—is referred to in this context as a positioning view. You use an anchor to express the relation between a popover and its positioning view.
Here's a link to the NSPopover class. You can also see an example of NSPopovers used in the Calendar (10.7+) app, and the Safari app (10.8+). The image below depicts a popover in the Calendar app (left) and Safari (right):
Here's how to setup an NSPopover, it is very simple and can be done mostly in interface builder.
Add an NSPopover Item to your XIB in interface builder. This will create the NSPopover and its view controller.
Next, drag a custom NSView into your XIB through interface builder. This will be the view for the popover view controller
Customize your NSView with any controls you need in your popover
In your header file (.h) add the following two lines of code:
#property (assign) IBOutlet NSPopover *popover;
- (IBAction)showPopover:(id)sender;
Don't forget to connect both the outlet and the action to your interface.
In your implementation, synthesize the popover and add the method for showPopover
In the showPopover method, add this line to show the popover:
[[self popover] showRelativeToRect:[sender bounds] ofView:sender preferredEdge:NSMaxYEdge];
It's up to you to figure out how to dismiss the popover; because what fun it copy / pasting? You can either do it manually (hint: try using close) or change the behavior property and have the system do it (see the edit below).
Good luck, hope this helps!
Edit
As noted by David in his comment:
Another possibility for dismissing the popover is to set its behavior to Transient. This allows the user to click anywhere outside the popover to have it disappear
The behavior property of a popover sets how it appears and disappears. There are three behaviors:
NSPopoverBehaviorApplicationDefined - (Default) Your app must close the popover itself
NSPopoverBehaviorTransient - The popover is closed when any interface element is interacted with outside the popover
NSPopoverBehaviorSemitransient - The popover is closed when any interface element in the popover's presenting view is interacted with outside the popover.
Read more about this in Apple's Documentation.
If I understood you correctly, you want something like MAAttachedWindow (by Matt Gemmell), which is open source.
Alternatively, you can take a look at Popover example in the documentation. https://developer.apple.com/library/mac/samplecode/Popover/Introduction/Intro.html