iphone - 传递一个对象上的UIToolbarButton行动

Question

是可能使一个UIToolbarButton传递对象到其目标通过使用一些方法明传（因为它似乎不使用常规的按钮用途是可能的）？

我的意思是这样

UIBarButtonItem *Button = [[UIBarButtonItem alloc] initWithImage:buttonImage
  style:UIBarButtonItemStylePlain target:self action:@selector(doSomething:) **withObject:usingThis**];

我知道我可以触发将与对象推出全法的方法，但优雅，我试图尽量减少代码的缘故...我怀疑这是不可能的，但你的球员，有有出奇的好，你可能会与超越的答案...谁知道...

Answer 1

您将不得不延长的UIBarButtonItem类。

下面是一个例子创建RCBarButtonItem类。我用initWithTitle为方便，我相信你可以改变它......

的子类的UIBarButtonItem

#import <UIKit/UIKit.h>

@interface RCBarButtonItem : UIBarButtonItem {
    id anObject;
}

@property (nonatomic, retain) id anObject;

- (id)initWithTitle:(NSString *)title style:(UIBarButtonItemStyle)style target:(id)target action:(SEL)action withObject:(id)obj;

@end

@implementation RCBarButtonItem

@synthesize anObject;

-(void)dealloc {
    [anObject release];
    [super dealloc];
}

- (id)initWithTitle:(NSString *)title style:(UIBarButtonItemStyle)style target:(id)target action:(SEL)action withObject:(id)obj {
    if (self = [super initWithTitle:title style:style target:target action:action]) {
        self.anObject = obj;
    }
    return self;
}

@end

那么这可能然后像这样来实现：

#import "RootViewController.h"
#import "RCBarButtonItem.h"

@implementation RootViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    RCBarButtonItem *button = [[RCBarButtonItem alloc] initWithTitle:@"Hello"
                                                               style:UIBarButtonItemStylePlain 
                                                              target:self
                                                              action:@selector(doSomething:)
                                                          withObject:@"Bye"];
    self.navigationItem.rightBarButtonItem = button;

}

- (void)doSomething:(id)sender {
    NSLog(@"%@", [(RCBarButtonItem *)sender anObject]);
}

Answer 2

我已经在这种情况下做的是创造一个NSDictionary属性调用，也就是说，buttonArguments：

self. buttonArguments = [[NSDictionary alloc] initWithObjectsAndKeys: usingThis, Button, ... , nil];

然后在您doSomething:方法，查找基于该sender参数的对象。

Answer 3

我更喜欢使用的类别：

  

的UIBarButtonItem + BarButtonItem.h

@interface UIBarButtonItem (BarButtonItem)
@property (strong, nonatomic) NSDictionary *userInfo;
@end

  

的UIBarButtonItem + BarButtonItem.m

static void *kUserInfo = &kUserInfo;

@implementation UIBarButtonItem (BarButtonItem)

- (NSDictionary *)userInfo {
    return objc_getAssociatedObject(self, kUserInfo);
}

- (void)setUserInfo:(NSDictionary *)userInfo {
    objc_setAssociatedObject(self, kUserInfo, userInfo, 
        OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

@end