Usually you would put the checks in the method below. That way whenever the app becomes active (including first time its launched) you can check the settings just prior to returning control to the user, no need to do polling in the background. For UIManagedDocument you may want to migrate the store to a local only copy and remove any iCloud content or the opposite, depending on the users input.
BTW just include the check in the previous answer to test if the global iCloud settings have been turned on or off. I don't do this because its only necessary to change the apps behaviour if the user has set the app specific settings.
/*! The app is about to enter foreground so use this opportunity to check if the user has changed any
settings. They may have changed the iCloud account, logged into or out of iCloud, set Documents & Data to off (same effect as
if they logged out of iCloud) or they may have changed the app specific settings.
If the settings have been changed then check if iCloud is being turned off and ask the user if they want to save the files locally.
Otherwise just copy the files to iCloud (don't ask the user again, they've just turned iCloud on, so they obviously mean it!)
@param application The application
*/
- (void)applicationWillEnterForeground:(UIApplication *)application
{
//LOG(@"applicationWillEnterForeground called");
// Check if the settings have changed
[[NSUserDefaults standardUserDefaults] synchronize];
NSUserDefaults* userDefaults = [NSUserDefaults standardUserDefaults];
bool userICloudChoice = [userDefaults boolForKey:_cloudPreferenceKey];
// Check against the current in memory setting
if (userICloudChoice == useICloudStorage) {
// The setting has not been changed so just ignore
//LOG(@" iCloud choice has not changed");
} else {
// The setting has changed so do something
//LOG(@" iCloud choice has been changed!!");
// iCloud has been turned off so ask the user if they want to keep files locally
if (!userICloudChoice) {
//LOG(@" Ask user if they want to keep iCloud files ?");
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) {
_cloudChangedAlert = [[UIAlertView alloc] initWithTitle:@"You're not using iCloud" message:@"What would you like to do with documents currently on this phone?" delegate:self cancelButtonTitle:@"Keep using iCloud" otherButtonTitles:@"Keep on My iPhone", @"Delete from My iPhone", nil];
} else {
_cloudChangedAlert = [[UIAlertView alloc] initWithTitle:@"You're not using iCloud" message:@"What would you like to do with documents currently on this phone?" delegate:self cancelButtonTitle:@"Keep using iCloud" otherButtonTitles:@"Keep on My iPad", @"Delete from My iPad", nil];
}
[_cloudChangedAlert show];
} else {
// iCloud has been turned on so just copy the files across, don't ask the user again...
//LOG(@" iCloud turned on so copy any created files across");
[[CloudManager sharedManager] setIsCloudEnabled:YES]; // This does all the work based on the settings passed to it
useICloudStorage = YES;
}
}
}
Oh and also register for this notification in case the user logs on using another iCloud account.
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(checkUserICloudPreferenceAndSetupIfNecessary) name:NSUbiquityIdentityDidChangeNotification object:nil];
