ios - How should I replace these screen size and device type macros in Swift?

Question

Back in Objective-C, I defined the following macros in a constants.h file:

#define IS_IPHONE5 (([[UIScreen mainScreen] bounds].size.height-568)?NO:YES)
#define IS_IPAD    (UI_USER_INTERFACE_IDIOM()==UIUserInterfaceIdiomPad)
#define IS_IOS7 ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7)
#define APP_DEFAULT_FONT_FACE @"HelveticaNeue-Light"
#define APP_DEFAULT_FONT_FACE_THIN @"HelveticaNeue-UltraLight"
#define APP_VERSION @"1.2"

I started playing with Swift and I noticed that these things just don't work anymore. So now how should I define these macros, and detect which family the device belongs to?

And if Swift doesn't have macros, what is the syntax of doing it?

Answer 1

I tend to use these three structs in every project i do:

struct ScreenSize {
    static let SCREEN_WIDTH         = UIScreen.mainScreen().bounds.size.width
    static let SCREEN_HEIGHT        = UIScreen.mainScreen().bounds.size.height
    static let SCREEN_MAX_LENGTH    = max(ScreenSize.SCREEN_WIDTH, ScreenSize.SCREEN_HEIGHT)
    static let SCREEN_MIN_LENGTH    = min(ScreenSize.SCREEN_WIDTH, ScreenSize.SCREEN_HEIGHT)
}

struct DeviceType {
    static let IS_IPHONE_4_OR_LESS  = UIDevice.currentDevice().userInterfaceIdiom == .Phone && ScreenSize.SCREEN_MAX_LENGTH < 568.0
    static let IS_IPHONE_5          = UIDevice.currentDevice().userInterfaceIdiom == .Phone && ScreenSize.SCREEN_MAX_LENGTH == 568.0
    static let IS_IPHONE_6          = UIDevice.currentDevice().userInterfaceIdiom == .Phone && ScreenSize.SCREEN_MAX_LENGTH == 667.0
    static let IS_IPHONE_6P         = UIDevice.currentDevice().userInterfaceIdiom == .Phone && ScreenSize.SCREEN_MAX_LENGTH == 736.0
    static let IS_IPAD              = UIDevice.currentDevice().userInterfaceIdiom == .Pad && ScreenSize.SCREEN_MAX_LENGTH == 1024.0
}

struct iOSVersion {
    static let SYS_VERSION_FLOAT = (UIDevice.currentDevice().systemVersion as NSString).floatValue
    static let iOS7 = (iOSVersion.SYS_VERSION_FLOAT < 8.0 && iOSVersion.SYS_VERSION_FLOAT >= 7.0)
    static let iOS8 = (iOSVersion.SYS_VERSION_FLOAT >= 8.0 && iOSVersion.SYS_VERSION_FLOAT < 9.0)
    static let iOS9 = (iOSVersion.SYS_VERSION_FLOAT >= 9.0 && iOSVersion.SYS_VERSION_FLOAT < 10.0)
}

And i use them in the following manner:

if DeviceType.IS_IPHONE_6 {
    //iPhone 6 specific code goes here.
}