这个功能使用说明是每次app更新或者第一次安装都需要显示的。你可以给每个需要显示的说明界面设置一个BOOL变量控制它是否显示。在applicationDidFinishLaunching的函数中判断app是第一次安装还是更新升级。
NSString *appVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleShortVersionString"];
NSString *appBuild = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];
if (![NSUserDefaults stringForKey:@"appVersion"] ||
![NSUserDefaults stringForKey:@"appBuild"] ||
![[NSUserDefaults stringForKey:@"appVersion"] isEqualToString:appVersion] ||
![[NSUserDefaults stringForKey:@"appBuild"] isEqualToString:appBuild]) {
[NSUserDefaults setBool:YES forKey:isFirstLaunch];
[NSUserDefaults setString:appVersion forKey:@"appVersion"];
[NSUserDefaults setString:appBuild forKey:@"appBuild"];
}