How do I programatically set the size of a view of an NSCollectionViewItem?
I tried doing this in an NSCollectionView subclass:
#implementation CustomCollectionView
- (NSCollectionViewItem *)newItemForRepresentedObject:(id)object {
NSCollectionViewItem *newitem = [[self itemPrototype] copy];
[newitem setRepresentedObject:object];
NSView *itemview = [newitem view];
[itemView setFrame:NSMakeRect([itemView frame].origin.x, [itemView frame].origin.y, [itemView frame].size.width, 500)];
return newitem;
}
#end
However this code has no effect. I tried subclassing my NSView that I use for the NSCollectionViewItem, and adding setFrame: to the initWithCoder method, but I get an EXC BAD ACCESS crash when I do that.
You might checkout this open source NSCollectionView alternative from Steven Degutis which, coincidentally I think was just posted to GitHub today (I noticed it today via Twitter):
http://github.com/sdegutis/SDListView
Looks like it allows you to have items with different heights.
Related
I need to add a save extension selector with a text label next to it to my NSSavePanel. In the screenshot attached I try to demonstrate that I succeeded in adding an NSComboBox to my panel with the function setAccessoryView. However I have no idea how to create a custom NSView, which includes both an NSComboBox and an NSTextView or equivalent. I found no tutorials on the internet (or if I found one it was extremely outdated) showing how to create custom NSViews in objective-C in Cocoa on MacOS.
How can I create a custom NSView containing a combobox and a text label? Or how can I add two "stock" NSViews to the same NSSavePanel? Please be as detailed in your answer as possible, as I have very limited objective-c experience.
You asked how to create an NSView in Objective-C with an NSTextField and an NSComboBox as subviews.
Basically, you could define them in Interface Builder and programmatically set the resulting view in Objective-C as the accessoryView of the NSSavePanel. Alternatively, the custom NSView could be created entirely in Objective-C, which is probably the easier option here.
After instantiating an NSView, you can use addSubview: to add an NSTextField and an NSComboBox accordingly. Then you can use NSLayoutConstraints to set up Auto Layout, which takes care of sizing the accessoryView and arranging the subviews properly based on the width of the dialog.
If you create the views programmatically and use Auto Layout, you must explicitly set translatesAutoresizingMaskIntoConstraints to NO.
Should you want to set the allowedContentTypes, a textual mapping of the displayed extension to UTType via a NSDictionary might be useful.
If you set the delegate of the NSComboBox to self, then you will be informed about changes of the user selection in the NSComboBox via comboBoxSelectionDidChange:.
If the things discussed are implemented appropriately in code, it might look something like this for a self-contained example:
#import <UniformTypeIdentifiers/UniformTypeIdentifiers.h>
#import "ViewController.h"
#interface ViewController () <NSComboBoxDelegate>
#property (nonatomic, strong) NSSavePanel *savePanel;
#property (nonatomic, strong) NSDictionary<NSString *, UTType*> *typeMapping;
#end
#implementation ViewController
- (instancetype)initWithCoder:(NSCoder *)coder {
if (self = [super initWithCoder:coder]) {
_typeMapping = #{
#"jpeg": UTTypeJPEG,
#"png": UTTypePNG,
#"tiff": UTTypeTIFF
};
}
return self;
}
- (NSView *)accessoryView {
NSTextField *label = [NSTextField labelWithString:#"Filetypes:"];
label.textColor = NSColor.lightGrayColor;
label.font = [NSFont systemFontOfSize:NSFont.smallSystemFontSize];
label.alignment = NSTextAlignmentRight;
NSComboBox *comboBox = [NSComboBox new];
comboBox.editable = NO;
for (NSString *extension in self.typeMapping.allKeys) {
[comboBox addItemWithObjectValue:extension];
}
[comboBox setDelegate:self];
NSView *view = [NSView new];
[view addSubview:label];
[view addSubview:comboBox];
comboBox.translatesAutoresizingMaskIntoConstraints = NO;
label.translatesAutoresizingMaskIntoConstraints = NO;
[NSLayoutConstraint activateConstraints:#[
[label.bottomAnchor constraintEqualToAnchor:view.bottomAnchor constant:-12],
[label.widthAnchor constraintEqualToConstant:64.0],
[label.leadingAnchor constraintEqualToAnchor:view.leadingAnchor constant:0.0],
[comboBox.topAnchor constraintEqualToAnchor:view.topAnchor constant:8.0],
[comboBox.leadingAnchor constraintEqualToAnchor:label.trailingAnchor constant:8.0],
[comboBox.bottomAnchor constraintEqualToAnchor:view.bottomAnchor constant:-8.0],
[comboBox.trailingAnchor constraintEqualToAnchor:view.trailingAnchor constant:-20.0],
]];
return view;
}
- (void)comboBoxSelectionDidChange:(NSNotification *)notification {
NSComboBox *comboBox = notification.object;
NSString *selectedItem = comboBox.objectValueOfSelectedItem;
NSLog(#"### set allowedContentTypes to %# (%#)", selectedItem, self.typeMapping[selectedItem]);
[self.savePanel setAllowedContentTypes:#[ self.typeMapping[selectedItem] ]];
}
- (IBAction)onSave:(id)sender {
NSWindow *window = NSApplication.sharedApplication.windows.firstObject;
self.savePanel = [NSSavePanel new];
self.savePanel.accessoryView = [self accessoryView];
[self.savePanel beginSheetModalForWindow:window completionHandler:^(NSModalResponse result) {
if (result != NSModalResponseOK) {
return;
}
NSURL *fileURL = self.savePanel.URL;
NSLog(#"### selectedFile: %#", fileURL);
}];
}
- (void)setRepresentedObject:(id)representedObject {
[super setRepresentedObject:representedObject];
}
#end
Finally, a screenshot of the above demo code in action looks like this:
Press Cmd-N to add a new file to your project. Choose a View file to add a xib file that has a custom view.
Open the xib file and add the controls to the custom view. Press the Add button in the project window toolbar to access the user interface elements.
Use the NSNib class to load the xib file and get the custom view.
I am working on a project for iOS 7.0+ with a storyboard, using Size Classes with AutoLayout and I'm using a UIView subclass backed by a xib file of the same name.
What I'am trying to do is I'am instantiating a UIView from xib programmatically and adding it to a ViewController from a Storyboard. This ViewController has AutoLayout up and running but the UIView I am adding doesn't respect the frame of the ViewController.
I'm instantiating my UIView subclass like this:
tabBarView = [[SHDTabBarView alloc] initWithFrame:CGRectMake(0, self.view.height-50, self.view.width, 50)];
[self.view addSubview:tabBarView];
And inside the subclass I'm using a set up of creating a UIView IBOutlet called container to instantiate it form code like this:
-(id)initWithFrame:(CGRect)frame{
self = [super initWithFrame:frame];
if (self == nil) return nil;
[self initalizeSubviews];
return self;
}
-(id)initWithCoder:(NSCoder *)aDecoder{
self = [super initWithCoder:aDecoder];
if (self == nil) return nil;
[self initalizeSubviews];
return self;
}
-(void)initalizeSubviews{
NSString *nibName = NSStringFromClass([self class]);
UINib *nib = [UINib nibWithNibName:nibName bundle:nil];
[nib instantiateWithOwner:self options:nil];
//Add the view loaded from the nib into self.
[self addSubview:self.container];
}
This is how my xib looks in the Interface Builder (notice the width of the canvas is 320 px):
And that's how it looks on the iPhone 6 (notice how it's getting cut off from the right side):
I've tried to use a multitude of solutions, including doing it all in code with an open-source solution PureLayout, using a manual constraint set up, etc.
None of my findings seem to work right. Ideally, I want to set up everything in Interface Builder, then just add the view to the superview of the ViewController with according frame and let AutoLayout do its magic.
How should I approach this task? Any advices are more than welcome.
Try to set the frame of your subview in the viewDidLayoutSubviews(). Looks like you init your subview before view fully layouted
In a controller I'm creating a UIScrollView. I'm trying to set this viewcontroller as the UISCrollview delegate and to implement the delegate's method in order to add (later) a UIPageControl.
I've read a bit, and found this link, this other link and other here on SO, and some useful tutorial all around the web, but I don't understand what I'm doing wrong. Everytime a scroll the UIScrollView, the app crashes with an EXC_BAD_ACCESS error.
Here's my .h file
#import <UIKit/UIKit.h>
#interface StatsViewController : UIViewController <UIScrollViewDelegate> {
UIScrollView *scrollView;
UIPageControl *pageControl;
}
#end
Then in my .m file, I'm creating the scrollview and trying to define the delegate method like this:
- (void)viewDidLoad {
[super viewDidLoad];
NSInteger boxWidth = self.view.frame.size.width;
NSInteger boxHeight = 412;
scrollView = [ [UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, boxHeight)];
scrollView.pagingEnabled = TRUE;
scrollView.delegate = self;
NSInteger numberOfViews = 2;
StatBreatheCounter *breatheCounter = [ [StatBreatheCounter alloc] init];
breatheCounter.view.frame = CGRectMake(0, 0, boxWidth, boxHeight);
[scrollView addSubview:breatheCounter.view];
BreatheLocationViewController *breatheLocation = [ [BreatheLocationViewController alloc] init];
breatheLocation.view.frame = CGRectMake(320, 0, boxWidth, boxHeight);
[scrollView addSubview:breatheLocation.view];
scrollView.contentSize = CGSizeMake(self.view.frame.size.width * numberOfViews, boxHeight);
[self.view addSubview:scrollView];
}
- (void)scrollViewDidScroll:(UIScrollView *)sender {
NSLog(#"RUNNING");
}
...but every time I slide on the scroll view, the app is crashing.
Now, I'm quite a n00b on Ojective-C, but I feel I'm missing something. Browsing around everything points on the fact that the delegate could be deallocated early, and when the user trigger the action, no one is handling the method (sorry for the explanation :)).
...but if the delegate it's the viewcontroller itself, how could it be deallocated?
As you can see, I'm quite confused :(
Any help would be really appreciated
--
EDIT:
I'm going to include here the solution founded thanks with your comments and answer.
When I posted my question I was so convinced that the error was coming from the way I was creating the UIScrollView and setting its delegate that I didn't realize that the problem was (as everything was suggesting, btw :)) I was allocating the StateViewController in its parent without declaring any "strong" reference to it (again, sorry for the explanation, I'm really a n00b in this).
Thanks a lot for your helping in pointing me on the right direction
It looks like you are losing reference to the delegate during scroll. I would look into any other release events around StatsViewController or other events that could cause it to be dereferenced.
Major head-scratcher all day on this one :-(
I have an instance of a UIPageViewController that does not appear to be firing the delegate method:
-(UIPageViewControllerSpineLocation)pageViewController:(UIPageViewController *)pageViewController
spineLocationForInterfaceOrientation:(UIInterfaceOrientation)orientation
I have tried various methods of displaying the UIPageViewController and have settled on a programatic approach (as opposed to a Storyboard one) that appears to be working correctly, with one exception... when rotating the iPad to landscape the spine does not appear mid-point as expected. I simply cannot find out why the delegate method does not get called.
Code Explanation (simplified for example)
Consider three classes as follows:
RootViewController - loaded when the app starts
PageViewController - loaded by RootViewController upon user initiation
PageContentViewController - loaded by PageViewController when pages are needed
Fairly self-explanatory. The RootViewController is loaded by the app upon launch. When the user taps an image within this view controller's view (think magazine cover opening a magazine) it launches the PageViewController as follows:
PageViewController *pvc = [[PageViewController alloc] initWithNibName:#"PageView"
bundle:[NSBundle mainBundle]];
pvc.view.frame = self.view.bounds;
[self.view addSubview:pvc.view];
In the actual app there is animation etc to make the transition all nice, but essentially the PageViewController's view is loaded and takes fullscreen.
PageViewController
This is the workhorse (only relevant methods shown). I have tried various examples from the infinite world of Google and written directly from the Apple docs...
#interface PageViewController : UIViewController <UIPageViewControllerDelegate, UIPageViewControllerDataSource>
#property (nonatomic, strong) UIPageViewController *pageViewController;
#property (nonatomic, strong) NSMutableArray *modelArray;
#end
#implementation TXCategoryController
-(void)viewDidLoad
{
[super viewDidLoad];
// Simple model for demo
self.modelArray = [NSMutableArray alloc] init];
for (int i=1; i<=20; i++)
[self.modelArray addObject:[NSString stringWithFormat:#"Page: %d", i]];
self.pageViewController = [[UIPageViewController alloc]
initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl
navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options:nil];
self.pageViewController.delegate = self;
self.pageViewController.dataSource = self;
PageContentViewController *startupVC = [[PageContentViewController alloc] initWithNibName:#"PageContent" bundle:nil];
startupVC.pageLabel = [self.modelArray objectAtIndex:0];
[self.pageViewController setViewControllers:[NSArray arrayWithObject:startupVC]
direction:UIPageViewControllerNavigationDirectionForward
animated:NO
completion:nil];
[self addChildViewController:self.pageViewController];
[self.view addSubview:self.pageViewController.view];
[self.pageViewController didMoveToParentViewController:self];
self.pageViewController.view.frame = self.view.bounds;
self.view.gestureRecognizers = self.pageViewController.gestureRecognizers;
}
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerBeforeViewController:(UIViewController *)viewController
{
// Relevant code to add another view...
}
-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController
viewControllerAfterViewController:(UIViewController *)viewController
{
// Relevant code to add another view...
}
-(UIPageViewControllerSpineLocation)pageViewController:(UIPageViewController *)pageViewController
spineLocationForInterfaceOrientation:(UIInterfaceOrientation)orientation
{
// Setting a break point in here - never gets called
if (UIInterfaceOrientationIsPortrait(orientation))
{
// Relevant code to create view...
return UIPageViewControllerSpineLocationMin;
}
// Relevant code to create 2 views for side-by-side display and
// set those views using self.pageViewController setViewControllers:
return UIPageViewControllerSpineLocationMid
}
#end
This all works perfectly well as I mentioned earlier. The PageViewController's view gets shown. I can swipe pages left and right in both portrait and landscape and the respective page number appears. However, I don't ever see two pages side-by-side in landscape view. Setting a breakpoint in the spineLocationForInterfaceOrientation delegate method never gets called.
This is such a head-scratcher I have burned out of ideas on how to debug/solve the problem. It almost behaves like the UIPageViewController isn't responding to the orientation changes of the device and therefore isn't firing off the delegate method. However, the view gets resized correctly (but that could be just the UIView autoresizing masks handling that change).
If I create a brand new project with just this code (and appropriate XIb's etc) it works perfectly fine. So something somewhere in my actual project is causing this. I have no idea where to continue looking.
As usual, any and all help would be very much appreciated.
Side Note
I wanted to add the tag 'uipageviewcontrollerspinelocation' but couldn't because it was too long and I didn't have enough reputation (1500 required). I think this is a devious ploy on Apple's part to avoid certain tags in Stackoverflow... ;-)
Finally found the problem. It was something of a red herring in its symptoms, but related just the same.
Putting a break point in the shouldAutorotateToInterfaceOrientation: method was a natural test to see if the UIViewController was even getting a rotation notification. It wasn't which led me to Apple's technical Q&A on the issue: http://developer.apple.com/library/ios/#qa/qa1688/_index.html
The most relevant point in there was:
The view controller's UIView property is embedded inside UIWindow but alongside an additional view controller.
Unfortunately, Apple, in its traditional documentation style, doesn't provide an answer, merely confirmation of the problem. But an answer on Stack Overflow yielded the next clue:
Animate change of view controllers without using navigation controller stack, subviews or modal controllers?
Although my RootViewController was loading the PageViewController, I was doing it as a subview to the main view. This meant I had two UIViewController's in which only the parent would respond to changes.
The solution to get the PageViewController to listen to the orientation changes (thus triggering the associated spine delegate method) was to remove addSubview: and instead present the view controller from RootViewController:
[self presentViewController:pac animated:YES completion:NULL];
Once that was done, the orientation changes were being picked up and the PageViewController was firing the delegate method for spine position. Only one minor detail to consider. If the view was launched in landscape, the view was still displaying portrait until rotated to portrait and back to landscape.
That was easily tweaked by editing viewDidLoad as follows:
PageContentViewController *page1 = [[PageContentViewController alloc] initWithNibName:#"PageContent" bundle:nil];
NSDictionary *pageViewOptions = nil;
NSMutableArray *pagesArray = [NSMutableArray array];
if (IS_IPAD && UIInterfaceOrientationIsLandscape(self.interfaceOrientation))
{
pageViewOptions = [NSDictionary dictionaryWithObject:[NSNumber numberWithInt:UIPageViewControllerSpineLocationMid]
forKey:UIPageViewControllerOptionSpineLocationKey];
PageContentViewController *page2 = [[PageContentViewController alloc] initWithNibName:#"PageContent" bundle:nil];
[pagesArray addObject:page1];
[pagesArray addObject:page2];
}
else
{
[pagesArray addObject:page1];
}
self.pageViewController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl
navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal
options:pageViewOptions];
self.pageViewController.delegate = self;
[self.pageViewController setViewControllers:pagesArray
direction:UIPageViewControllerNavigationDirectionForward
animated:NO
completion:NULL];
Job done and problem solved.
recently I started using storyboard and I've the following situation: I want to set the text of an UILabel from the AppDelegate. So I created an instance of my ViewController
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"MainStoryboard"
bundle: nil];
ViewController *controller = (ViewController*)[mainStoryboard
instantiateViewControllerWithIdentifier: #"mainViewController"];
myViewController = controller;
[window addSubview:myViewController.view];
[window makeKeyAndVisible];
and called the following method from the delegate
- (void) updateParameterLabel:(NSString *)parameter {
NSLog(#"URL-2: %#", parameter);
parameterLabel.text = parameter;
}
But the parameter is not shown in the UI.
Another think, which is kind of strage:
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
NSLog(#"View did Appear");
}
The "View did appear" is logged twice ...
Any hints?
Regards,
Sascha
Setting the text of a UILabel from your application delegate isn't great design. Your view controllers should be managing the content of your views, hence their name. Typically your storyboard is instantiated automatically, and you don't need any of the storyboardWithName et code you've got, assuming you're working with Apple's default templates.
Maybe think about re-architecting your application to follow the 'model-view-controller' pattern more strictly, and also look at how Apple instantiate storyboards automatically (just create a new storyboard project in XCode to see this).
If you still want to make it work, make the UILabel a property of your viewcontroller and set the label by using
In delegate :
- (void) updateParameterLabel:(NSString *)parameter {
NSLog(#"URL-2: %#", parameter);
[myViewController updateParemeter:parameter];
}
In myViewController:
- (void) updateParameterLabel:(NSString *)parameter {
NSLog(#"URL-2: %#", parameter);
parameterLabel.text = parameter;
[self.view setNeedsDisplay];//edit
}
So use the viewController to update your label. Of course you need the label as a property in your viewController
For what I see you are trying to update the label before it appears, so why don't you try calling your updateLabel method in the viewWillAppear, it would be something like this
-(void)viewWillAppear:(BOOL)animated{
[self updateParameterLabel:#"Some Text"];
[super viewWillAppear:YES];
}
And updateParameterLabel has to be implemented in the viewController.