Multiple ViewControllers with same background - ios

Question

How can one still background image in multiple view controllers be implemented?
With self.view.backgroundColor = UIColor(patternImage: UIImage(named: "file.png")) background would move along with UIViewController while screen switching.
Is it possible to place image on separate layer under view controllers?

Answer 1

Solution 1
Create a class called MyBackground:
class MyBackground {
class func addBackgroundImage() {
UIGraphicsBeginImageContext(self.view.frame.size)
UIImage(named: "file")?.drawInRect(self.view.bounds)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
view.backgroundColor = UIColor(patternImage: image)
}
}
If you want to call it in your AViewController, simply call MyBackground.addBackgroundImage()
Solution 2
Create a ViewController called MyViewController:
class MyViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
addBackgroundImage()
}
func addBackgroundImage() {
UIGraphicsBeginImageContext(self.view.frame.size)
UIImage(named: "file")?.drawInRect(self.view.bounds)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
view.backgroundColor = UIColor(patternImage: image)
}
}
If you AViewController want to set this image, simply do like this:
AViewController: MyViewController //AViewController is a subclass of MyViewController
For example: I have an image call background, and I will set it as a background image of my ViewController:
If I just add it in one line as #startupthekid said:
If I add it as I said:

Answer 2

i think you can set background in your container view controllers, such as navi controller, tab controller, then set all your view controller's background to clear color.

Answer 3

A better answer is to use UIAppearance. If you're not familiar with it, UIAppearance is a proxy protocol that you send messages to and it modifies later instances of that class.
For example if I have a custom button class RoundButton:
RoundButton.appearance().titleFont = Font.Heavy(20)
And in my RoundButton class:
dynamic var titleFont: UIFont? {
get { return self.titleLabel?.font }
set { self.titleLabel?.font = newValue }
}
The dynamic keywords is incredibly important. It's used for objective-c compatibility and setting properties via UIAppearance that don't use it will cause a crash.
You can do as many custom properties as you want and there's a bunch already default in the os.
In your case you can do something like:
UIImageView.appearanceWhenContainedInInstancesOfClasses([MyCustomViewController.self)].customImage = UIImage(...)
You can of course get away with just a custom view controller but in my opinion, UIApperance keeps your UI code separate from your controller logic.
One way you could implement the behavior you want is a UIViewController subclass:
class MyCustomViewController: UIViewController {
private let backgroundImageView = UIImageView()
dynamic var backgroundImage: UIImage? {
get { self.backgroundImageView.image }
set { self.backgroundImageView.image = newValue }
}
}
and then modify the backgroundImage property on the appearance instance of MyCustomViewController.
MyCustomViewController.appearance().backgroundImage = ...
EDIT: Given that your question was misleading and that you instead want a shared image that never moves throughout all your view controllers, you can simply insert an image view into the application window:
if let window = UIApplication.sharedApplication().windows.first {
let imageView = UIImageView(image: UIImage(named: "face-mask"))
window.addSubview(imageView)
imageView.frame = window.bounds
}
If you like Autolayout, like I do, then I'd set constraints to pin the image view to the window edges.

Answer 4

you should set the image in viewDidload of every viewController
Update :
either you should set in every view controller or you can set to windows . Second thing if your background changes dynamically with different images then you can use prepareforsegue method to pass images to nextviewcontroller if images are different for each viewcontroller. if same image for every viewcontroller then you can set it to window.
:)