I presumed this would be simple but it is not working.
I am trying to pass an NSArray to my UIView that is getting imported with a NIB.I am importing it as:
DraggableViewBackground *draggableBackground = [[DraggableViewBackground alloc]initWithFrame:frame];
draggableBackground.exampleCardLabels = #[#"Mercedes-Benz", #"BMW", #"Porsche",
#"Opel", #"Volkswagen", #"Audi"];
[self.ripContainer addSubview:draggableBackground];
On my DraggableViewBackground UIView
.h
#property (retain,nonatomic)NSArray* exampleCardLabels;
.m
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
[super layoutSubviews];
NSLog(#"Dish RIP %#", exampleCardLabels);
}
return self;
}
I am currently getting a null value. I am aware this is 101 basics when passing data but I don't understand why this isn't working.
It's just timing.
At this stage the array has not been set:
DraggableViewBackground *draggableBackground = [[DraggableViewBackground alloc]initWithFrame:frame];
and yet you are logging the array in the initWithFrame method. Log it later on in the lifecycle.
Also don't call [super layoutSubviews]; in the initWithFrame method.
Make your init like this:
- (id)initWithFrame:(CGRect)frame andCards:(NSArray *)cards{
self = [super initWithFrame:frame];
if (self){
self.xampleCardLabels = cards;
}
return self;
}
and call it
DraggableViewBackground *draggableBackground = [[DraggableViewBackground alloc]
initWithFrame: frame
andCards: #[#"Mercedes-Benz", #"BMW", #"Porsche",#"Opel", #"Volkswagen", #"Audi"]];
Related
How is this possible?
PlayingCardView *view = [[PlayingCardView alloc] initWithFrame:currentFrame];
if ([view isKindOfClass:[PlayingCardView class]])
NSLog(#"checked!");
The if below doesn't work. However, it says that my view is of UIView class, not the PlayingCardView, which is inherited from the UIView. The problem is that because of it I can't send PlayingCardView's messages to my view.
update:
- (instancetype) initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
[self setup];
return self;
}
It is possible if you override initWithFrame for PlayingCardView the wrong way. You might be doing something like self = [[UIView alloc] initWithFrame:] instead of self = [super initWithFrame:]. Check any init methods that you have overridden for PlayingCardView.
I have tried modify my code many times, but still can't pass variable from UIViewController to UIView, variable always return (null).
// BPGraphView.h
#interface BPGraphView : UIView
#property (nonatomic, retain) NSString *test;
#end
// BPGraphView.m
#import "BPGraphView.h"
#implementation BPGraphView
#synthesize test;
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
NSLog(#"test %#",test);
if (self) {
// Initialization code
}
return self;
}
- (void)drawRect:(CGRect)rect
{
NSLog(#"draw %#", test); // always return (null)
if ([test isEqual:#"something"]) {
[self drawOutLine];
}
}
#end
// BloodPressureViewController.m
- (void)viewDidLoad
{
BPGraphView * graphview=[[BPGraphView alloc] init];
graphview.test = #"something";
}
In your code:
- (void)viewDidLoad
{
BPGraphView * graphview=[[BPGraphView alloc] init];
graphview.test = #"dd";
}
The variable graphview is basically destroyed once the viewDidLoad is run to finish. It will never get a chance to run drawRect.
Now the question is how should you define a instance variable of BPGraphView in your UIViewController. The easiest way should be adding a BPGraphView onto your view's xib file and link to an IBOutlet in your UIViewController. In this way, you should be able to assign to test
#IBOutlet BPGraphView graphview;
- (void)viewDidLoad
{
graphview.test = #"dd";
}
Without setting a frame, drawRect will not be called.
BPGraphView * graphview=[[BPGraphView alloc] initWithFrame:CGRectMake(0, 0, 200, 200)];
graphview.test = #"something";
[self.view addSubview:graphview];
I tried this,it works well,in your code,drawRect is not called
BPGraphView * graphview=[[BPGraphView alloc] init];
graphview.test = #"dd";
[graphview drawRect:CGRectMake(0, 0, 0, 0)];
I can't intercept the init function that's getting called when it's getting created inside of the xib file.
I want to add borderline to it when it gets created so that I won't need to add it manually.
.h:
#import <UIKit/UIKit.h>
#interface UITextView (FITAddBorderline)
- (id) init;
- (id) initWithFrame:(CGRect)frame;
#end
.m:
#import "UITextView+FITAddBorderline.h"
#implementation UITextView (FITAddBorderline)
- (id) init
{
self = [super init];
if (self) {
[self addBorderline];
}
return self;
}
- (id) initWithFrame:(CGRect)frame {
self = [super init];
if (self) {
self.frame = frame;
[self addBorderline];
}
return self;
}
- (void) addBorderline {
//To make the border look very close to a UITextField
[self.layer setBorderColor:[[[UIColor grayColor] colorWithAlphaComponent:0.5] CGColor]];
[self.layer setBorderWidth:2.0];
//The rounded corner part, where you specify your view's corner radius:
self.layer.cornerRadius = 5;
self.clipsToBounds = YES;
}
#end
Views that come from NIBs are initialized with initWithCoder:
- (id)initWithCoder:(NSCoder *)aDecoder
{
self = [super initWithCoder:aDecoder];
if (self)
{
[self addBorderline];
}
return self;
}
As a side note, I would recommend changing what you are doing and use a subclass instead of a category. You can get yourself into some trouble overriding methods in a category. See more info here.
You just need to implement the awakeFromNib method:
-(void)awakeFromNib
{
[super awakeFromNib];
[self addBorderline];
}
I've created a view with a variable and loaded it in the loadView method of a view controller. How do I pass a value to the view variable from the view controller after the loadView method has been called?
LocationView.m
#import "LocationView.h"
#implementation LocationView
#synthesize locationTitle;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
locationTitle = [[UILabel alloc]initWithFrame:CGRectMake(10, 10, 300, 20)];
[self addSubview:locationTitle];
}
return self;
}
LocationViewController.m
#import "LocationViewController.h"
#import "LocationView.h"
#interface LocationViewController ()
#end
#implementation LocationViewController
- (void)loadView
{
CGRect frame = [[UIScreen mainScreen] bounds];
LocationView *locationView = [[LocationView alloc] initWithFrame:frame];
[self setView:locationView];
}
- (void)viewDidLoad
{
[super viewDidLoad];
How do I pass a value to locationTitle here?
}
You've already set up the locationTitle property for LocationView objects, so you can just access that. The only thing you need to do beforehand is keep a reference to the LocationView object around in an instance variable so you can access it from any instance method.
#implementation LocationViewController {
LocationView *_locationView;
}
- (void)loadView
{
CGRect frame = [[UIScreen mainScreen] bounds];
_locationView = [[LocationView alloc] initWithFrame:frame];
[self setView:_locationView];
}
- (void)viewDidLoad
{
[super viewDidLoad];
_locationView.locationTitle = #"Test";
}
#end
Alternatively, since you are assigning the custom view to the view controllers main view, you could cast that:
- (void)viewDidLoad
{
[super viewDidLoad];
((LocationView *)self.view).locationTitle = #"Test";
}
If I have a class that is setup like this to customize a UIView.
#interface myView : UIView
- (id)init {
self = [super init];
if(self){
[self foo];
}
return self;
}
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
[self foo];
}
return self;
}
-(void) foo{
//Build UIView here
}
How come foo is called twice whether I use
myView *aView = [[myView alloc]init]];
or
myView *aView = [[myView alloc]initWithFram:aFrame];
UIView init calls UIView initWithFrame:. Since you override both, calling your init method results in your initWithFrame: method being called:
In other words: your init calls UIView init. UIView init calls initWithFrame:. Since you override initWithFrame:, your initWithFrame: is called which in turn calls UIView initWithFrame:.
The solution, since your initWithFrame: will always be called, is to remove the call to foo from your init method.