检查我的IOS应用程序是否已更新
我需要检查我的应用程序是否在更新时启动,因为我需要创建一个仅在首次安装该应用程序时才出现的视图,以便在更新后再次出现。
回答:
您可以将值(例如,当前应用程序版本号)保存到其中,NSUserDefaults
并在每次用户启动应用程序时对其进行检查。
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{
// ...
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *currentAppVersion = [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleShortVersionString"];
NSString *previousVersion = [defaults objectForKey:@"appVersion"];
if (!previousVersion) {
// first launch
// ...
[defaults setObject:currentAppVersion forKey:@"appVersion"];
[defaults synchronize];
} else if ([previousVersion isEqualToString:currentAppVersion]) {
// same version
} else {
// other version
// ...
[defaults setObject:currentAppVersion forKey:@"appVersion"];
[defaults synchronize];
}
return YES;
}
在迅速-2版本看起来是这样的:
let defaults = NSUserDefaults.standardUserDefaults()let currentAppVersion = NSBundle.mainBundle().objectForInfoDictionaryKey("CFBundleShortVersionString") as! String
let previousVersion = defaults.stringForKey("appVersion")
if previousVersion == nil {
// first launch
defaults.setObject(currentAppVersion, forKey: "appVersion")
defaults.synchronize()
} else if previousVersion == currentAppVersion {
// same version
} else {
// other version
defaults.setObject(currentAppVersion, forKey: "appVersion")
defaults.synchronize()
}
在迅速-3版本看起来是这样的:
let defaults = UserDefaults.standardlet currentAppVersion = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as! String
let previousVersion = defaults.string(forKey: "appVersion")
if previousVersion == nil {
// first launch
defaults.set(currentAppVersion, forKey: "appVersion")
defaults.synchronize()
} else if previousVersion == currentAppVersion {
// same version
} else {
// other version
defaults.set(currentAppVersion, forKey: "appVersion")
defaults.synchronize()
}
以上是 检查我的IOS应用程序是否已更新 的全部内容, 来源链接: utcz.com/qa/401466.html