UiBarButtonItem selector.. on click crash

Question

I am stuck in a small problem,

I dynamically create a UIBarButtonItem using this code..

UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(didSelectPopitDownFromNavBar:)];

self.navigationItem.rightBarButtonItem = rightButton;

and the selector method is this..

-(IBAction)didSelectPopitDownFromNavBar:(id)sender event:(UIEvent *)event

so it gives a crash on click.. how can i pass this event..?

Always post the error message with such a question. Though in this case it was obvious. — rmaddy, Feb 28 '14 at 19:45

score 5 · Accepted Answer · answered Feb 28 '14 at 19:44

5

All of the parameters form part of the method signature, so your button would need to use:

@selector(didSelectPopitDownFromNavBar:event:)

but this probably isn't going to do what you want as the button will only expect to pass itself (as the sender).

answered Feb 28 '14 at 19:44

Wain

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wouldnt that be sending a nil event...? – Ahmed Z. Feb 28 '14 at 19:44
1

Of course the other solution to this issue would be to change the method to `-(IBAction)didSelectPopitDownFromNavBar:(id)sender {`. In other words, drop the `event` parameter. This assumes the `event` isn't needed by the handler. – rmaddy Feb 28 '14 at 19:46
does it pass an event? Can't say I've ever tried with 2 params – Wain Feb 28 '14 at 19:46
@rmaddy.. event parameter is needed by the handler.. em using a library that needs it.. – Ahmed Z. Feb 28 '14 at 19:49
OK then Wain's answer is the proper solution. – rmaddy Feb 28 '14 at 19:49
@rmaddy yes exactly... just waiting for the timer to end for selecting the answer – Ahmed Z. Feb 28 '14 at 19:51
2

On iOS, the event will be correctly passed as the second argument for control events. – Jesse Rusak Feb 28 '14 at 19:51

score 2 · Answer 2 · edited May 23 '17 at 10:26

If your function was

UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemBookmarks target:self action:@selector(didSelectPopitDownFromNavBar:)];
...
-(IBAction )didSelectPopitDownFromNavBar:(id)sender

It shouldn't crash, the problem is likely the selector isn't properly defined,

see this question - Passing parameters on button action:@selector

UiBarButtonItem selector.. on click crash

2 Answers2