Incorrect positioning of background image - swift - ios

Question

I'm using an image in the background of the application. This image is displayed correctly in one clip, while the other clip is positioned incorrectly. In the correct picture(fig .1), the background image is positioned up to Tabbar. As you can see in the wrong picture(fig .2), the background is not positioned up to Tabbar and the logo is left behind Tabbar. The codes are in the same state, but the picture is incorrectly positioned in Fig .2.
MainTableViewController Class
class MainTableViewController: UITableViewController
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
appThemeSetBySettingsPreference()
}
func appThemeSetBySettingsPreference() {
UIGraphicsBeginImageContext(view.frame.size)
UIImage(named: "...png")?.draw(in: view.bounds)
if let image = UIGraphicsGetImageFromCurrentImageContext(){
UIGraphicsEndImageContext()
view.backgroundColor = UIColor(patternImage: image)
}
}
}
DeviceViewController Class
class DeviceViewController: UITableViewController
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
appThemeSetBySettingsPreference()
}
func appThemeSetBySettingsPreference() {
UIGraphicsBeginImageContext(view.frame.size)
UIImage(named: "...png")?.draw(in: view.bounds)
if let image = UIGraphicsGetImageFromCurrentImageContext(){
UIGraphicsEndImageContext()
view.backgroundColor = UIColor(patternImage: image)
}
}
}
EDIT
let image = UIImageView(image: UIImage(contentsOfFile:"...."));
let tabBarHeight = tabBarController?.tabBar.frame.size.height
let topBarHeight = UIApplication.shared.statusBarFrame.size.height + (self.navigationController?.navigationBar.frame.height ?? 0.0)
image.frame = CGRect(x:0 , y: topBarHeight, width: self.view.frame.size.width , height: self.view.frame.size.height - topBarHeight - tabBarHeight!)

Answer 1

With the iPhone X, the height of the top bar (navigation bar + status bar) is changed. So you can get exact height of the top bar (both navigation bars + status bar):
Swift 4:
let topBarHeight = UIApplication.shared.statusBarFrame.size.height +(self.navigationController?.navigationBar.frame.height ?? 0.0)
Swift 3:
let topBarHeight = UIApplication.sharedApplication().statusBarFrame.size.height + (self.navigationController?.navigationBar.frame.height ?? 0.0)
Objective-C:
CGFloat topbarHeight = ([UIApplication sharedApplication].statusBarFrame.size.height + (self.navigationController.navigationBar.frame.size.height ?: 0.0));
And the height of the tab bar can be obtained as follows
let tabBarHeight = self.tabBarController?.tabBar.frame.height ?? 49.0
Having these values ​​you can adapt your image to when starting your controller in your method viewDidLoad() of your class, for example
self.image.frame = CGRect(x:0 , y: topBarHeight, width: self.view.frame.size.width , height: self.view.frame.size.height - topBarHeight - tabBarHeight)