requestAccessToEntity iOS6- Backwards compatibili

问题:

following iOS6 eventKit and the new privacy settings I am using the following code - which works perfectly fine on iOS6 devices.

Still, I would like the same code to work also for devices with iOS 5.x and I wish not to write a the "same code" twice - Seems wrong.

Can anyone assist in an elegant solution ?

 EKEventStore *eventStore = [[EKEventStore alloc] init];
    [eventStore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error) {

// some code 


}];

回答1:

I'm using this:

void (^addEventBlock)();

addEventBlock = ^
{
    NSLog(@"Hi!");
};

EKEventStore *eventStore = [[UpdateManager sharedUpdateManager] eventStore];

if ([eventStore respondsToSelector:@selector(requestAccessToEntityType:completion:)])
{
    [eventStore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error)
     {
         if (granted)
         {   
             addEventBlock();
         }
         else
         {
             NSLog(@"Not granted");
         }
     }];
}
else
{
    addEventBlock();
}

I think that should reduce code duplication.

回答2:

If you show the event in a modalviewcontroller with a EKEventEditViewController, iOS automatically show you a view saying what to do if the permission is denied. So, I do this:

In viewDidLoad:

eventStore = [[EKEventStore alloc] init];

In the method used to add the event:

if ([eventStore respondsToSelector:@selector(requestAccessToEntityType:completion:)])
{
    __block typeof (self) weakSelf = self; // replace __block with __weak if you are using ARC
    [eventStore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error)
     {
         if (granted)
         {   
             [weakSelf performSelectorOnMainThread:@selector(addEventToCalendar) withObject:nil waitUntilDone:YES];
         }
         else
         {
             NSLog(@"Not granted");
         }
     }];
}
else
{
    [self addEventToCalendar];
}

回答3:

I have an EventUtil.m file with

+(void)proxyForIOS6EventKitToCallFunction:(SEL)function WithViewController:(UIViewController*)viewController {
    #pragma clang diagnostic push
    #pragma clang diagnostic ignored "-Warc-performSelector-leaks"
    AppDelegate *app = (AppDelegate*)[[UIApplication sharedApplication] delegate];
    if([app.eventStore respondsToSelector:@selector(requestAccessToEntityType:completion:)]) {
        // For iOS 6
        MBProgressHUD *hud = [MBProgressHUD showHUDAddedTo:viewController.view animated:YES];
        hud.labelText = @"";
        //invoke requestAccessToEntityType...
        [app.eventStore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error) {
            //Handle the response here…
            //Note: If you prompt the user, make sure to call the main thread
            if (granted == YES) {
                dispatch_async(dispatch_get_main_queue(), ^{
                    [viewController performSelector:function];
                });
            }
        }];
    }
    else {
        [viewController performSelector:function];
    }
    #pragma clang diagnostic pop
}

And in the view controller that I want to access the calendar I import the EventUtil.h file and call this function:

[EventUtil proxyForIOS6EventKitToCallFunction:@selector(displayModifyCalendarAlertView) WithViewController:self];

displayModifyCalendarAlertView is the function I want to call if the calendar permission is given (either iOS6 or iOS < 6).