I came across the exception 'NSInternalInconsistencyException' when I write the code below in a viewcontroller which is associated with storyboard:
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self) {
self.view.backgroundColor = [UIColor blackColor];
}
return self;
}
However, if I delete the line 'self.view.backgroundColor = [UIColor blackColor];', there is no problem. I don`t know the reason.
Actually, in the stroyboard I have several controllers, and I want to make a base controller for all the controllers. The purpose is that I want to set a background view(UIView) for them.
I try to add a UIView in the viewDidLoad method of the basecontroller, but the view covers any components that set in the storyboard. I think the reason is that the components on the sub viewcontrollers are initialized in the 'initWithCoder' method before the 'ViewDidLoad' method is called. So I try to add the bgView in the 'initWithCoder' method of the basecontroller, and this led to the problem above.
So I also want to know a right way to achieve my purpose. Thanks!
dont set graphics related properties in init and bring subview to front. Set them from
-(void)awakeFromNib
{
[self.view.superview bringSubviewToFront:self.view];
self.view.backgroundColor = [UIColor blackColor];
}
Related
I am subclassing an UIButton which is going to be present in all of my app's ViewControllers, kinda Navigation Button. I would like just to put it to my VC and apply custom class, without any code in ViewController itself. So, the questions:
1. is it possible?
2. I am using this code now in my UIButton custom class. What is wrong?:
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[self addTarget:self action:#selector(didTouchButton) forControlEvents:UIControlEventTouchUpInside];
}
return self;
}
- (void)didTouchButton {
NSLog(#"YEAH, it works, baby!");
}
UPD: seems that even initWithFrame method is not being called at all.
Loading from the nib I think.The initWithFrame method doesn't work if not called programatically.
Try -awakeFromNib Method
See this question
Where should I initialize a UITablewView as a subview, in - (id)initWithFrame:(CGRect)frame, in viewdidload or loadView? Which is the better approach? Where should I make the frame (I mean which is more effective)?
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self)
{
self.backgroundColor = kViewBackgroundColor;
_tableView = [[UITableView alloc] initWithFrame:CGRectZero style:UITableViewStyleGrouped];
_tableView.backgroundView = nil;
_tableView.backgroundColor = [UIColor clearColor];
_tableView.bounces = NO;
[self addSubview:_tableView];
}
return self;
}
On my projects I usually create a baseViewController with a custom initialiser like this:
- (id)init{
self = [self initWithNibName:NSStringFromClass([self class]) bundle:[NSBundle mainBundle]];
if (self) {
//You should create the tableView and other properties here
//and add as subviews inside viewDidLoad
_tableView = [[UITableView alloc]initWithFrame:CGRectMake(0,0,100,100)];
}
return self;
}
and I always create my view controller by using this init method, because I don't think the other vc's need to know the name of the nib file. If I were you I would create subviews inside init method, add as subviews inside viewDidLoad or viewWillAppear and finally releasing them inside dealloc if you are not using ARC.
Generally this depends on your requirement that if you are having custom view called with a tableview as subview then loadview with the initwithframe method will be better and while you want to initialize it from viewcontroller then viewdidload is better. I think you should bifurcate your requirement. Hope this helps.
Since you are initializing table view with zero frame it wont be visible even if you added that
you can try this
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self)
{
self.backgroundColor = kViewBackgroundColor;
UITableView *_tableView = [[UITableView alloc] initWithFrame:self.bounds style:UITableViewStyleGrouped];
_tableView.backgroundView = nil;
_tableView.backgroundColor = [UIColor clearColor];
_tableView.bounces = NO;
[_tableView setAutoresizingMask:UIViewAutoresizingFlexibleHeight|UIViewAutoresizingFlexibleWidth]
[self addSubview:_tableView];
}
return self;
}
If you'd like to create subviews programmatically based on superview metrics (frame or bounds), you should do it in viewDidLoad, because if you do in in initializer, metrics of self.view will not be avaliable, and you subviews will be created with zero frame and will not be visible (as Johnykutty) mentioned above.
But that does not seem to be a good practice in case your subview initialization routines require heavy operations.
Offtopic: I've been codin' for a looong time trying to do everything programmatically, never using xibs, etc. Well, if you ask me now, xibs really save your time and make life easier. Consider using interface builder for layout\autolayout, colors\borders etc stuff.
I am designing a custom view controller in interface builder with a XIB file and I have a custom UIView subclass that I want to add to my view controller. Here is how I've put my custom view into the view controller:
My TonerEffectButtonView class is a subclass of UIView (and has nothing to do with UIButton) and here is my code for it:
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
}
return self;
}
-(void)prepareWithSelector:(SEL)selector onTarget:(id)targ withFilter:(GPUImageFilter*)filter{
self.gpuImageView = [[GPUImageView alloc] initWithFrame:self.frame];
UITapGestureRecognizer *gesture = [[UITapGestureRecognizer alloc] initWithTarget:targ action:selector];
[self addGestureRecognizer:gesture];
selectedFilter = filter;
[filter addTarget:self.gpuImageView];
[self setNeedsDisplay];
}
- (void)drawRect:(CGRect)rect
{
[super drawRect:rect];
}
initWithFrame: is not called anyway as I'm creating the view through a XIB, and I don't need any customization in initWithCoder: so I haven't implemented it. I have a GPUImageView (that is a part of a library that I'm using) that I'm creating programatically inside my view, and adding camera input to it (if you ask what happens in the prepare method). Prepare method is called from outside, and I've verified my UIView's frame is correct when it is called. I have a breakpoint on [super drawRect:rect]; and it never gets called, and when I run the program, my custom view is not displayed, nor does receive touch events (but prepare method DOES get called so the instance is created with the correct frame). It's like it has never been put there in interface builder. What could be the cause of this? I've seen many posts about this, and they mostly refer to creating views programatically and indicating problems with 'initWithFrame:'. But I have nothing to do with that method, and I want to use the interface builder/XIB couple, please don't advice me to create the view controller programatically. What could be the cause of it?
Thanks,
Can.
UPDATE: I can verify that -(void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx is also not called in any way.
Ok, I've found the answer. First, I've tried to add another instance programatically, and I've found out that it has autoresizing mask set to none, whereas my original instance has it set to W+H. This clue made me realize that in fact, I was forgetting to add my GPUImageView instance as a subview into my custom view. I've added it, and it worked.
I am wanting to create a custom UIView class that will show a dynamic number of UISegmentedControl objects depending on some input. For example, if a client has 5 products in their cart, the UIView should generate 5 UISegmentedControl objects that I will then link with each item.
The problem I am having is getting this to work in a UIView. Here is what I have done so far. I am successfully able to create a UISegmentedControl object and display it programmatically within my main UIViewController. I don't get any display when adding it to my UIView class. Here is the implementation code for the UIView class:
#import "ajdSegmentView.h"
#implementation ajdSegmentView
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
NSArray *itemArray = [NSArray arrayWithObjects:#"Yes", #"No", nil];
UISegmentedControl *button = [[UISegmentedControl alloc] initWithItems:itemArray];
button.frame = CGRectMake(35,44, 120,44);
button.segmentedControlStyle = UISegmentedControlStylePlain;
button.selectedSegmentIndex = 1;
[self addSubview:button];
}
return self;
}
#end
I created a new UIView object via Storyboard and placed it inside the UIViewController scene. I made sure to set the class from the generic UIView class to my new custom class. I added and outlet for the UIView in my UIViewController class. Here is the code inside the implementation of UIViewController:
#import "ajdViewController.h"
#interface ajdViewController ()
#end
#implementation ajdViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
self.segmentView = [[ajdSegmentView alloc] init];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end
That's all I have tried. I have been searching through a lot of pages and trying to implement this without asking here, but I seem to be looking in the wrong places.
First you need to check ajdSegmentView is UIVIew or UIViewController. It is fine if it is UIView. If it is type of UIViewController then you need to add this line while adding Segment.
[self.view addSubview:button];
In place of:
[self addSubview:button];
And One more thing You forget to add this View to your main after allocating so You can declare like this:
objajdSegmentView = [[ajdSegmentView alloc] init];
[self.view addSubview:objajdSegmentView.view];
I have just added this thing. i got result like this way.
Hope this will work for you.
You're initializing your custom view using the init method, but your initialization for ajdSegmentView is in your initWithFrame: method (which in your case is not getting called).
So replace:
self.segmentView = [[ajdSegmentView alloc] init];
with:
// Change the frame to what you want
self.segmentView = [[ajdSegmentView alloc] initWithFrame:CGRectMake(0,0,100,40)];
Also don't forget to add your view to the view controller's view also.
[self.view addSubview:self.segmentView];
Unless this view is being created with interface builder, in which case you will need to override initWithCoder: in your ajdSegmentView class.
I'm not familiar with Storyboard though, so maybe I'm missing something, but in a standard scenario what I said above will solve your problem.
I have some custom appearance properties in my view class (a descendant of UIView). I want to customize the view appearance according to these properties, but I can’t do that inside the initializer, since the values set using [[MyClass appearance] setFoo:…] aren’t in effect at that point:
#interface View : UIView
#property(strong) UIColor *someColor UI_APPEARANCE_SELECTOR;
#end
#implementation View
#synthesize someColor;
// Somewhere in other code before the initializer is called:
// [[View appearance] setSomeColor:[UIColor blackColor]];
- (id) initWithFrame: (CGRect) frame
{
self = [super initWithFrame:frame];
NSLog(#"%#", someColor); // nil
return self;
}
#end
They are already set in layoutSubviews, but that’s not a good point to perform the view customizations, since some customizations may trigger layoutSubviews again, leading to an endless loop.
So, what’s a good point to perform the customizations? Or is there a way to trigger the code that applies the appearance values?
One possible workaround is to grab the value directly from the proxy:
- (id) initWithFrame: (CGRect) frame
{
self = [super initWithFrame:frame];
NSLog(#"%#", [[View appearance] someColor); // not nil
return self;
}
Of course this kills the option to vary the appearance according to the view container and is generally ugly. Second option I found is to perform the customizations in the setter:
- (void) setSomeColor: (UIColor*) newColor
{
someColor = newColor;
// do whatever is needed
}
Still I’d rather have some hook that gets called after the appearance properties are set.
Why not wait until
- (void)willMoveToSuperview:(UIView *)newSuperview {
[super willMoveToSuperview:newSuperview];
if (newSuperview) {
... code here ...
}
}
if it's giving you trouble?
I believe UIAppearance properties are applied to a view when it is being added into a view hierarchy. So presumably you could access the set properties in UIView didMoveToSuperview.
Caveat: I am using Swift 2, so not sure about earlier versions of Swift / Objective-C. But I have found that didMoveToSuperview() will not work. The properties are available in layoutSubviews(), but that's not a great place to do anything like this (since it can be called more than once). The best place to access these properties in the lifeCycle of the view I have found is didMoveToWindow().
I would have thought that viewDidLoad would be best if it's a one-time thing. Otherwise, viewWillAppear.
EDIT:
If you want to do it in the view, and not it's controller then I would create a custom init for the view along the lines of:
-(id) initWithFrame:(CGRect) frame andAppearanceColor:(UIColor)theColor;
thereby passing the colour into the view at creation time.