Disable all subviews in a IBOutletCollection - ios

Question

I want to disable/enable all UIViews in a IBOutletCollection.
However the UIViews differ in class, so I can't call the setEnabled directly.
Then I thought I would use the performSelector method to do it, however I can only send an Object as parameter.
I read both on this site and on other sites that I could just use [NSNumber numberWithBool YES/NO], however the enabled state doesn't change when sending a NSNumber with either bool YES or NO.
I got the disabled part to work by using nil, however I couldn't find a way to set it them enabled:
-(void) setControlsState: (BOOL) enabled
{
for(UIView *subview in controls)
{
NSNumber *boolObject = enabled? [NSNumber numberWithBool: YES]: nil;
if([subview respondsToSelector: #selector(setEnabled:)])
{
[subview performSelector: #selector(setEnabled:) withObject: boolObject];
}
else if([subview respondsToSelector: #selector(setEditable:)])
{
[subview performSelector: #selector(setEditable:) withObject: boolObject];
}
subview.alpha = enabled? 1: 0.5;
}
}
Where controls is a IBOutletCollection consisting of UISliders, UIButtons, UITextViews and UITextfields. (#property (strong, nonatomic) IBOutletCollection(UIView) NSArray *controls;)
Note: The UITextViews works fine wit the above code, it is only the other type of UIViews, which uses setEnabled.

Answer 1

Is there a specific reason your not using userInteractionEnabled which disallows touch events?
-(void) setControlsState: (BOOL) enabled
{
for(UIView *aView in controls)
{
if ([aView isKindOfClass:[UIView class]]){
aView.userInteractionEnabled = enabled;
aView.alpha = (enabled)?1.0:0.5;// Be mindful of this it doesn't seem to respect group opacity. i.e. sliders look funny.
}
}
}
If there is you can simply cast the aView pointer after checking it's class, like so: (Of course you'll have to enumerate through all the classes you use)
-(void) setControlsState: (BOOL) enabled
{
for(UIView *aView in controls)
{
if ([aView isKindOfClass:[UISlider class]]){
[(UISlider *)aView setEnabled:enabled];
}
if ([aView isKindOfClass:[UITextView class]]){
[(UITextView *)aView setEditable:enabled];
}
// and so forth
}
}

Answer 2

I came up against this problem myself yesterday. In my case, setting userInteractionEnabled wasn't sufficient, because I wanted the controls to appear greyed out, not just stop responding to touch events. I also had some UIView subclasses with custom enabled/disabled behavior, and I didn't want to have to enumerate all classes as #NJones suggested in case I add more controls in the future.
As the OP noted, using NSNumber does not work. The solution is to use NSInvocation as explained in TomSwift's answer to this question. I decided to wrap this in a convenience function:
void XYPerformSelectorWithBool(id obj, SEL selector, BOOL boolean)
{
NSMethodSignature *signature = [[obj class] instanceMethodSignatureForSelector:selector];
NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature];
[invocation setSelector:selector];
[invocation setArgument:&boolean atIndex:2];
[invocation invokeWithTarget:obj];
}
Then disabling all controls is as simple as:
for (UIView *view in controls)
if ([view respondsToSelector:#selector(setEnabled:)])
XYPerformSelectorWithBool(view, #selector(setEnabled:), NO);