Alternate Icon in iOS 10.3: avoid notification dialog for icon change

Question

I'm using this new feature and when the change is made with an active application, a notification dialog is displayed saying that icon has been modified. How to disable this dialog ?

Answer 1

If you don't mind making use of private method, you can try the following code.

- (void)lc_setAlternateIconName:(NSString*)iconName
{
    //anti apple private method call analyse
    if ([[UIApplication sharedApplication] respondsToSelector:@selector(supportsAlternateIcons)] && 
        [[UIApplication sharedApplication] supportsAlternateIcons])
    {
        NSMutableString *selectorString = [[NSMutableString alloc] initWithCapacity:40];
        [selectorString appendString:@"_setAlternate"];
        [selectorString appendString:@"IconName:"];
        [selectorString appendString:@"completionHandler:"];

        SEL selector = NSSelectorFromString(selectorString);
        IMP imp = [[UIApplication sharedApplication] methodForSelector:selector];
        void (*func)(id, SEL, id, id) = (void *)imp;
        if (func)
        {
            func([UIApplication sharedApplication], selector, iconName, ^(NSError * _Nullable error) {});
        }
    }
}

Answer 2

Adding to Andrew's Swift 5 rewrite of Robert's answer (as I don't have the reputation to comment).

For the default icon we need to pass nil, so iconName should be an optional.

func setApplicationIconName(_ iconName: String?) {
        if UIApplication.shared.responds(to: #selector(getter: UIApplication.supportsAlternateIcons)) && UIApplication.shared.supportsAlternateIcons {
            
            typealias setAlternateIconName = @convention(c) (NSObject, Selector, NSString?, @escaping (NSError) -> ()) -> ()
            
            let selectorString = "_setAlternateIconName:completionHandler:"
            
            let selector = NSSelectorFromString(selectorString)
            let imp = UIApplication.shared.method(for: selector)
            let method = unsafeBitCast(imp, to: setAlternateIconName.self)
            method(UIApplication.shared, selector, iconName as NSString?, { _ in })
        }
    }

Answer 3

Rewrote Robert's answer in Swift. The app hasn't been rejected as well.

func setApplicationIconName(_ iconName: String) {
        if UIApplication.shared.responds(to: #selector(getter: UIApplication.supportsAlternateIcons)) && UIApplication.shared.supportsAlternateIcons {
            
            typealias setAlternateIconName = @convention(c) (NSObject, Selector, NSString, @escaping (NSError) -> ()) -> ()
            
            let selectorString = "_setAlternateIconName:completionHandler:"
            
            let selector = NSSelectorFromString(selectorString)
            let imp = UIApplication.shared.method(for: selector)
            let method = unsafeBitCast(imp, to: setAlternateIconName.self)
            method(UIApplication.shared, selector, iconName as NSString, { _ in })
        }
    }

Answer 4

From the above Answer from Robert

- (void)lc_setAlternateIconName:(NSString*)iconName
{
    //anti apple private method call analyse
    if ([[UIApplication sharedApplication] respondsToSelector:@selector(supportsAlternateIcons)] && 
        [[UIApplication sharedApplication] supportsAlternateIcons])
    {
        NSMutableString *selectorString = [[NSMutableString alloc] initWithCapacity:40];
        [selectorString appendString:@"_setAlternate"];
        [selectorString appendString:@"IconName:"];
        [selectorString appendString:@"completionHandler:"];

        SEL selector = NSSelectorFromString(selectorString);
        IMP imp = [[UIApplication sharedApplication] methodForSelector:selector];
        void (*func)(id, SEL, id, id) = (void *)imp;
        if (func)
        {
            func([UIApplication sharedApplication], selector, iconName, ^(NSError * _Nullable error) {});
        }
    }
}

I couldn't make the line

void (*func)(id, SEL, id, id) = (void *)imp;

For me it had to be

void (*func)(id, SEL, id, id) = (void (*)(id, SEL, id, id))imp;