我需要检查我的应用程序启动时是否正在更新,因为我需要
以使得只有当应用程序首次安装才能再次出现才会出现
更新.
以使得只有当应用程序首次安装才能再次出现才会出现
更新.
解决方法
您可以将值(例如当前应用程序版本号)保存到NSUserDefaults,并在每次用户启动应用程序时进行检查.
- (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;
}
swift版本看起来像这样：
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()
}
