iOS－target－action設計模式瞭解，ios-target-action

iOS－target－action設計模式瞭解，ios-target-action

iOS－target－action設計模式瞭解

target－action的設計模式的本質就是在host中產生的事件調用target的action方法。

下面我們通過一個UIView來實現UIButton的點擊事件。

@interface CustomButton : UIView-(void)addCustomButton:(id)target andSelector:(SEL)action;@end@implementation CustomButton{    id _target;    SEL _action;}-(void)addCustomButton:(id)target andSelector:(SEL)action{    if (target==_target) {        return;    }        _target = target;    _action = action;}-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{}-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{    if (_target) {        if ([_target respondsToSelector:_action]) {            [_target performSelector:_action withObject:self];        }    }}

使用

- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view, typically from a nib.        CustomButton *btn = [[CustomButton alloc]initWithFrame:CGRectMake(0, 100, 200, 200)];    btn.backgroundColor = [UIColor redColor];    [btn addCustomButton:self andSelector:@selector(hello:)];    [self.view addSubview:btn];    }-(void)hello:(id)sender{    NSLog(@"hello customer ");}

運行結果

2015-03-29 17:09:03.803 Target_action[1863:89334] hello customer 

運行記憶體狀態：