UIButton+RBExtras.m

//
// UIButton+RBExtras.m
//
// Copyright (c) 2011 Robert Brown
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#import <objc/runtime.h>

#import "UIButton+RBExtras.h"


char * const UIButtonActionBlock = "UIButtonActionBlock";


@implementation UIButton (RBExtras)

- (void)performActionBlock {
    
    dispatch_block_t block = self.actionBlock;
    
    if (block)
        block();
}

- (dispatch_block_t)actionBlock {
    return objc_getAssociatedObject(self, UIButtonActionBlock);
}

- (void)setActionBlock:(dispatch_block_t)actionBlock {
    
    if (actionBlock != self.actionBlock) {
        [self willChangeValueForKey:@"actionBlock"];
        
        objc_setAssociatedObject(self, UIButtonActionBlock, actionBlock, OBJC_ASSOCIATION_COPY);
        
        // Removes the old action if any.
        [self removeTarget:self
                    action:@selector(performActionBlock)
          forControlEvents:UIControlEventTouchUpInside];
        
        // Adds the new action.
        [self addTarget:self
                 action:@selector(performActionBlock)
       forControlEvents:UIControlEventTouchUpInside];
        
        [self didChangeValueForKey:@"actionBlock"];
    }
}

@end