__block modifier creates unreadable memory - ios

Question

Now Im developing a banner showing feature in iOS
It's a singleton which shows banner on the upper part of screen when user logs in.
It's basically a shared view with a class method showWithName...
#interface XXUserWelcomeBanner ()
{
UIImageView *logoView;
UILabel *textLabel;
CGFloat _width;
}
#end
When user calls, it creates a UIImageView and a UILabel to add on self. And animates itself onto the screen.
+ (XXUserWelcomeBanner *)shared {
static dispatch_once_t onceToken;
static XXUserWelcomeBanner *userWelcomBanner;
dispatch_once(&onceToken, ^{
userWelcomBanner = [[XXUserWelcomeBanner alloc] init];
});
return userWelcomBanner;
}
+ (void)showWithUserName:(NSString *)userID andLogo:(UIImage * _Nullable)logo {
dispatch_async(dispatch_get_main_queue(), ^{
[[self shared] createWithName:userID andLogo:logo];
});
}
So there's this other bug I just found that causes this method to be called twice and on the second time it shows only the UIImageView.
And I don't understand why that's happening.
Because the UIImageView and UILabel won't be created twice.
Here's more code.
#pragma mark - private
- (void)createWithName:(NSString *)name andLogo:(UIImage * _Nullable)logo {
self.opaque = NO;
self.alpha = 0.9;
self.backgroundColor = COLOR(0xfcfcfc);
// if (#available(iOS 13.0, *)) {
// self.backgroundColor = UIColor.secondarySystemBackgroundColor;
// }
CGSize labelSize = CGSizeZero;
if (logoView == nil) {
if (logo != nil) {
logoView = [[UIImageView alloc] initWithImage:logo];
[self addSubview:logoView];
} else {
NSString *imagePath = [XXUtility pathForResourceNamed:#"Logo" withExtension:#"png"];
UIImage *imageToAdd = [[UIImage alloc] initWithContentsOfFile:imagePath];
logoView = [[UIImageView alloc] initWithImage:imageToAdd];
[self addSubview:logoView];
}
}
if (textLabel == nil) {
textLabel = [[UILabel alloc] init];
NSString * labelString = [NSString stringWithFormat:NSLocalizedStringWithDefaultValue(#"welcom banner", #"userInterface", [XXUtility bundleForStrings], #"Dear %#, welcome into game", #"user welcome banner text"), name];
labelSize = [labelString sizeWithAttributes:#{NSFontAttributeName : textLabel.font}];
textLabel.text = labelString;
[self addSubview:textLabel];
}
NSLog(#"XXUserWelcomeBanner Label size is %f x %f", labelSize.height, labelSize.width);
[self bannerSizeWithLabelSize:labelSize];
CGFloat bannerHeight = self.frame.size.height;
CGFloat bannerWidth = self.frame.size.width;
CGFloat logoHeight = bannerHeight * 0.45;
CGFloat logoWidth = logoHeight;
CGFloat logoXPos = (bannerWidth - logoWidth - labelSize.width) / 2;
CGFloat logoYPos = (bannerHeight - logoHeight) / 2;
CGFloat labelHeight = labelSize.height;
CGFloat labelWidth = labelSize.width;
CGFloat labelXPos = logoXPos + logoWidth + 5;
CGFloat labelYPos = (bannerHeight - labelHeight) / 2;
logoView.frame = CGRectMake(logoXPos, logoYPos, logoWidth, logoHeight);
textLabel.frame = CGRectMake(labelXPos, labelYPos, labelWidth, labelHeight);
[self bannerShow];
}
- (void)bannerSizeWithLabelSize:(CGSize)lSize {
_width = 40 + lSize.width + 5;
CGFloat height = 40;
CGFloat xPosition = ScreenWidth * 1/2 - _width * 1/2;
CGFloat yPosition = - height;
self.frame = CGRectMake(xPosition, yPosition, _width, height);
}
- (void)bannerShow {
UIViewController *vc;
if ([TOP_VIEWCONTROLLER respondsToSelector:#selector(topViewController)]) {
vc = [TOP_VIEWCONTROLLER topViewController];
} else {
vc = TOP_VIEWCONTROLLER;
}
[vc.view addSubview:self];
[UIView animateWithDuration:0.6 delay:0.2 options:UIViewAnimationOptionCurveEaseOut animations:^{
CGFloat height = 40;
CGFloat xPos = ScreenWidth * 1/2 - self->_width * 1/2;
CGFloat yPos = height * 1/3 + KiPhoneXSafeAreaDValue;
self.frame = CGRectMake(xPos, yPos, self->_width, height);
} completion:^(BOOL finished) {
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[UIView animateWithDuration:0.6 delay:0.2 options:UIViewAnimationOptionCurveEaseIn animations:^{
CGFloat height = 40;
CGFloat xPosition = ScreenWidth * 1/2 - self->_width * 1/2;
CGFloat yPosition = - height;
self.frame = CGRectMake(xPosition, yPosition, self->_width, height);
} completion:^(BOOL finished) {
[self bannerDestroy];
self.alpha = 0;
}];
});
}];
}
- (void)bannerDestroy {
[logoView removeFromSuperview];
[textLabel removeFromSuperview];
logoView = nil;
textLabel = nil;
[self removeFromSuperview];
}
- (void)dealloc
{
//
NSLog(#"uiview dealloc");
}
/*
// Only override drawRect: if you perform custom drawing.
// An empty implementation adversely affects performance during animation.
- (void)drawRect:(CGRect)rect {
// Drawing code
}
*/
#end
Thanks in advance.

Answer 1

It is expected that createWithName:andLogo: is calling more than once in your app. I guess you call it with different arguments, that's why it should not be inside dispatch_once(&onceToken, ^{ });. But you can optimise XXUserWelcomeBanner's init:
- (instancetype)init {
self = [super init];
if (self) {
logoView = [[UIImageView alloc] init];
[self addSubview:logoView];
textLabel = [[UILabel alloc] init];
[self addSubview:textLabel];
}
return self;
}
In createWithName:andLogo: you will have the following:
if (logo != nil) {
logoView.image = logo;
} else {
NSString *imagePath = [XXUtility pathForResourceNamed:#"Logo" withExtension:#"png"];
UIImage *imageToAdd = [[UIImage alloc] initWithContentsOfFile:imagePath];
logoView.image = imageToAdd;
}
NSString * labelString = [NSString stringWithFormat:NSLocalizedStringWithDefaultValue(#"welcom banner", #"userInterface", [XXUtility bundleForStrings], #"Dear %#, welcome into game", #"user welcome banner text"), name];
CGSize labelSize = [labelString sizeWithAttributes:#{NSFontAttributeName : textLabel.font}];
textLabel.text = labelString;