time delay on focus action - ios

Question

I've got a Collection View and have arranged it in such a way that there is a single column on one side of the screen and content that is replaced based on what collection item is in focus.
I'd like to be able to on swap the content out if focus on an item has been held for more then .5 seconds.
Here is what I currently have, and it swaps the data out instantly.
if self.focused {
self.label.alpha = 1
self.priceLabel.alpha = 1
if self.representedDataItem?.imageUrl! == "https://s3-us-west-2.amazonaws.com/random/image.png" ||
self.representedDataItem?.imageUrl! == "" {
self.backgroundImage.image = UIImage(named: "titleImage")
}
else {
ImageCache.sharedLoader.imageForUrl((self.representedDataItem?.imageUrl!)!, completionHandler:{(image: UIImage?, url: String) in
self.backgroundImage.image = image!
})
}
}
else {
self.label.alpha = 0.2
self.priceLabel.alpha = 0.2
}

Answer 1

Don't know the self.focused how to determine, assume you already took care of it. Therefore, you could use GCD to delay the execution while focused.
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(0.5 * Double(NSEC_PER_SEC))), dispatch_get_main_queue()) {
// code to be executed after 0.5 sec
}

Answer 2

if self.focused {
self.label.alpha = 1
self.priceLabel.alpha = 1
}
else {
self.label.alpha = 0.2
self.priceLabel.alpha = 0.2
}
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(0.5 * Double(NSEC_PER_SEC))), dispatch_get_main_queue()) {
// code to be executed after 0.5 sec
if self.focused {
if self.representedDataItem?.imageUrl! == "https://s3-us-west-2.amazonaws.com/random/image.png" ||
self.representedDataItem?.imageUrl! == "" {
self.backgroundImage.image = UIImage(named: "titleImage")
}
else {
ImageCache.sharedLoader.imageForUrl((self.representedDataItem?.imageUrl!)!, completionHandler:{(image: UIImage?, url: String) in
self.backgroundImage.image = image!
})
}
}
}