iOS trouble loading an image file to view from view controller programmatically - ios

Question

I have a view with a property that should take an NSString from my view controller and display an image. If I hard code locationImageFile with "320x213-1.png" in my view, the image displays properly, but if I try to set locationImageFile from my view controller, the image doesn't appear. I feel like I'm missing something pretty basic. Side note: I seem to be able to set the locationTitle property from my view controller without any problems.
LocationViewController.m
#import "LocationViewController.h"
#import "LocationView.h"
#implementation LocationViewController
{
LocationView *_locationView;
}
- (void)loadView
{
CGRect frame = [[UIScreen mainScreen] bounds];
_locationView = [[LocationView alloc] initWithFrame:frame];
[self setView:_locationView];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
_locationView.locationTitle.text = aLocation.name;
_locationView.locationImageFile = #"320x213-1.png";
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end
LocationView.m
#import "LocationView.h"
#implementation LocationView
#synthesize locationTitle;
#synthesize locationImageFile;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
[self setBackgroundColor: [UIColor blueColor]];
// Image container
UIImage *locationImage = [UIImage imageNamed:locationImageFile];
UIImageView *locationImageContainer = [[UIImageView alloc] initWithImage:locationImage];
[locationImageContainer setTranslatesAutoresizingMaskIntoConstraints:NO];
locationImageContainer.backgroundColor = [UIColor yellowColor];
[self addSubview:locationImageContainer];
// Text line
locationTitle = [[UILabel alloc]init];
[locationTitle setTranslatesAutoresizingMaskIntoConstraints:NO];
locationTitle.backgroundColor = [UIColor whiteColor];
[self addSubview:locationTitle];
}
return self;
}
#end

Answer 1

I think this is because the loadView method are invoke earlier than viewDidLoad method.
so when you set _locationView.locationImageFile = #"320x213-1.png";,the containerView's image are not being set.
You can consider declare locationImageContainer as a property of locationView , and set it's image directly.like
_locationView.locationImageContainer.image = [UIImage imageNamed:#"320x213-1.png"];
instead of setting locationImageFile as a property.

Answer 2

When LocationView is initialized, the value of the instance variable locationImageFile equals nil. Override the setter of the locationImageFile property inside LocationView.m like this:
- (void)setLocationImageFile:(NSString *)aLocationImageFile
{
locationImageFile = aLocationImageFile;
locationImageContainer.image = [UIImage imageNamed:aLocationImageFile];
}

Answer 3

You can try, doing it like this:
_locationView.locationImageFile = [UIImage imageNamed:locationImageFile];
if you did it like this:
_locationView.locationImageFile = locationImageFile;