How to check iOS version?
The quick answer …
As of Swift 2.0, you can use #available
in an if
or guard
to protect code that should only be run on certain systems.
if #available(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion]
in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to avoid relying on the operating system version as an indication of device or OS capabilities. There is usually a more reliable method of checking whether a particular feature or class is available.
Checking for the presence of APIs:
For example, you can check if UIPopoverController
is available on the current device using NSClassFromString
:
if (NSClassFromString(@"UIPopoverController")) {
// Do something
}
For weakly linked classes, it is safe to message the class, directly. Notably, this works for frameworks that aren't explicitly linked as "Required". For missing classes, the expression evaluates to nil, failing the condition:
if ([LAContext class]) {
// Do something
}
Some classes, like CLLocationManager
and UIDevice
, provide methods to check device capabilities:
if ([CLLocationManager headingAvailable]) {
// Do something
}
Checking for the presence of symbols:
Very occasionally, you must check for the presence of a constant. This came up in iOS 8 with the introduction of UIApplicationOpenSettingsURLString
, used to load Settings app via -openURL:
. The value didn't exist prior to iOS 8. Passing nil to this API will crash, so you must take care to verify the existence of the constant first:
if (&UIApplicationOpenSettingsURLString != NULL) {
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];
}
Comparing against the operating system version:
Let's assume you're faced with the relatively rare need to check the operating system version. For projects targeting iOS 8 and above, NSProcessInfo
includes a method for performing version comparisons with less chance of error:
- (BOOL)isOperatingSystemAtLeastVersion:(NSOperatingSystemVersion)version
Projects targeting older systems can use systemVersion
on UIDevice
. Apple uses it in their GLSprite sample code.
// A system version of 3.1 or greater is required to use CADisplayLink. The NSTimer
// class is used as fallback when it isn't available.
NSString *reqSysVer = @"3.1";
NSString *currSysVer = [[UIDevice currentDevice] systemVersion];
if ([currSysVer compare:reqSysVer options:NSNumericSearch] != NSOrderedAscending) {
displayLinkSupported = TRUE;
}
If for whatever reason you decide that systemVersion
is what you want, make sure to treat it as an string or you risk truncating the patch revision number (eg. 3.1.2 -> 3.1).
Check OS version in Swift?
For iOS, try:
var systemVersion = UIDevice.current.systemVersion
For OS X, try:
var systemVersion = NSProcessInfo.processInfo().operatingSystemVersion
If you just want to check if the users is running at least a specific version, you can also use the following Swift 2 feature which works on iOS and OS X:
if #available(iOS 9.0, *) {
// use the feature only available in iOS 9
// for ex. UIStackView
} else {
// or use some work around
}
BUT it is not recommended to check the OS version. It is better to check if the feature you want to use is available on the device than comparing version numbers.
For iOS, as mentioned above, you should check if it responds to a selector;
eg.:
if (self.respondsToSelector(Selector("showViewController"))) {
self.showViewController(vc, sender: self)
} else {
// some work around
}
How do you check/change iOS version in React Native?
Use Xcode to change an iOS project's target target iOS version. XCode > Project Navigator > "General" tab > Deployment Info > Target. You will the "ios/Quevera.xcodeproj/project.pbxproj" file will now have an entry like "IPHONEOS_DEPLOYMENT_TARGET = 11.0;".
How can I determine the latest iOS version programmatically using Swift?
Apple provides an API at curl http://ax.phobos.apple.com.edgesuite.net/WebObjects/MZStore.woa/wa/com.apple.jingle.appserver.client.MZITunesClientCheck/version
. Test it on the command line using:
curl http://ax.phobos.apple.com.edgesuite.net/WebObjects/MZStore.woa/wa/com.apple.jingle.appserver.client.MZITunesClientCheck/version
The response is XML, and the information you need is keyed by device version (eg iPhone8,1
).
You can access your device's version by using sysctlbyname()
from Swift.
Update Looks like the old URL (http://phobos.apple.com./version
) died a while back (thanks Troy) so have updated my answer with another version. I have no idea if the content is the same.
Related Topics
Passing Data Between View Controllers
Undefined Symbols For Architecture Arm64
How to Symbolicate Crash Log Xcode
Attempt to Set a Non-Property-List Object as an Nsuserdefaults
How to Get Current Location from User in Ios
Custom Uitableviewcell from Nib in Swift
Iphone Keyboard Covers Uitextfield
-Didselectrowatindexpath: Not Being Called
How to Change the Title of the "Back" Button on a Navigation Bar
Vertically Align Text to Top Within a Uilabel
Nsurlsession/Nsurlconnection Http Load Failed on iOS 9
How to Run Cocoapods on Apple Silicon (M1)
How to Create a Uicolor from a Hex String
How to Use Timer (Formerly Nstimer) in Swift