iOS 原生的 UIButton 點擊事件是不允許帶多參數的,唯一的一個參數就是默認UIButton本身
那麼我們該怎麼實現傳遞多個參數的點擊事件呢?
1.如果業務場景非常簡單,要求傳單參數並且是整數類型,可以用tag
[cell.deleteButton setTag:indexPath.row]; //例如,將cell的行數設置成tag
2.利用ObjC關聯,runtime之所以被稱為iOS 的動態特性是有道理的,當然關聯甚至可以幫助NSArray等其他對象實現“多參數傳遞”
實現起來也非常簡便:
UIButton *btn = // create the button
objc_setAssociatedObject(btn, "firstObject", someObject, OBJC_ASSOCIATION_RETAIN_NONATOMIC); //實際上就是KVC
objc_setAssociatedObject(btn, "secondObject", otherObject, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
[btn addTarget:self action:@selector(click:) forControlEvents:UIControlEventTouchUpInside];
- (void)click:(UIButton *)sender
{
id first = objc_getAssociatedObject(btn, "firstObject"); //取參
id second = objc_setAssociatedObject(btn, "secondObject");
// etc.
}3.利用自定義,添加一個多參數的字典屬性變量即可(為什麼要字典?可以裝多多的)
自定義Button子類,甚至都不用重寫啥的:
@interface MultiParamButton : UIButton @property (nonatomic, strong) NSDictionary* multiParamDic; @end
傳參:
NSDictionary* paramDic = @{@"one":@"one", @"two":@2, @"third":@(3)};
MultiParamButton* multiParamButton = [[MultiParamButton alloc] init];
[multiParamButton setFrame:CGRectMake(0, 0, 50, 50)];
multiParamButton.center = self.view.center;
[multiParamButton setBackgroundColor:[UIColor grayColor]];
[multiParamButton addTarget:self action:@selector(multiParamButtonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:multiParamButton];
multiParamButton.multiParamDic = paramDic;點擊:
- (void)multiParamButtonClicked:(UIButton* )button
{
MultiParamButton* multiParamButton = (MultiParamButton* )button;
NSLog(@"Vvvverify : %@", multiParamButton.multiParamDic);
}爽爽的:
當然,如果用擴展,然後添加property後重寫GetSet也是一樣一樣的
4.完全不在Button上入手,針對業務來,最常見的就是在TableViewCell上面的Button,這種存在(視圖)繼承樹之間的傳遞,這裡舉個簡單的例子
Button獲取所屬父視圖的所屬視圖控制器的參數,間接傳參
#import "LBMultiParamButtonController.h"
#import "MultiParamButton.h"
@interface LBMultiParamButtonController ()
@property (nonatomic, strong) NSDictionary* paramDic;
@end
@implementation LBMultiParamButtonController
- (id)init
{
self = [super init];
if (self)
{
_paramDic = @{@"one":@"one", @"two":@2, @"third":@(3)};
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
UIButton* button = [UIButton buttonWithType:UIButtonTypeCustom];
[button setFrame:CGRectMake(0, 0, 50, 50)];
[button setCenter:self.view.center];
[button setBackgroundColor:[UIColor grayColor]];
[button addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button];
}
- (void)buttonClicked:(UIButton* )button
{
LBMultiParamButtonController* multiParamButtonController = nil;
//獲取button所屬的視圖控制器,如果視圖控制器都能獲取,還有什麼不能獲取呢?
for(UIView* next = [button superview]; next; next = next.superview)
{
UIResponder *nextResponder = [next nextResponder];
if ([nextResponder isKindOfClass:[LBMultiParamButtonController class]])
{
multiParamButtonController = (LBMultiParamButtonController* )nextResponder;
break;
}
}
NSLog(@"param : %@", multiParamButtonController.paramDic);
}
@end這種非常多的用在UITableViewCell上自定義的按鈕的參數的情況!
5.利用Delegate和performSelector:withObject:withObject 方法可以傳遞最多兩個參數:
定義protocol:
#pragma mark - SYAccountListCellDelegate. @class SYAccountListCell; @protocol SYAccountListCellDelegate- (void)accountListCell:(SYAccountListCell* )cell didTapButton:(UIButton* )button; @end
自定義Cell的時候將你想傳的東西傳進入,這裡用cell和button做例子:
@implementation SYAccountListCell
- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];
if (self)
{
self.deleteButton = [UIButton buttonWithType:UIButtonTypeCustom];
[self.deleteButton setFrame:CGRectMake(225,
5,
40,
40)];
[self.deleteButton setBackgroundColor:[UIColor redColor]];
[self.deleteButton addTarget:self action:@selector(deleteButtonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.contentView addSubview:self.deleteButton];
}
return self;
}
- (void)deleteButtonClicked:(UIButton* )button
{
if ([self.delegate respondsToSelector:@selector(accountListCell:didTapButton:)])
{
[self.delegate performSelector:@selector(accountListCell:didTapButton:) withObject:self withObject:button];
}
}
@endDelegate實現:
#pragma mark - SYAccountListCellDelegate.
- (void)accountListCell:(SYAccountListCell *)cell didTapButton:(UIButton *)button
{
NSLog(@"Cell : %@ , Button : %@", cell, button);
}雖然有點曲折,但是傳參效果非常到位
這裡補充一下,這裡的最多兩個參數是直面的參數個數,如果將參數設置位結構體,那麼就皆大歡喜啦,想怎麼傳就怎麼傳!
6.利用Block 和 關聯 , 直接可以當前點擊並且操作參數 - 強!
#importtypedef void (^ActionBlock)(); @interface UIButton (Utility) @property (readonly) NSMutableDictionary *event; - (void) handleControlEvent:(UIControlEvents)controlEvent withBlock:(ActionBlock)action; @end
實現文件:
#import#import "UIButton+Utility.h" @implementation UIButton (Utility) static char overviewKey; @dynamic event; - (void)handleControlEvent:(UIControlEvents)event withBlock:(ActionBlock)block { objc_setAssociatedObject(self, &overviewKey, block, OBJC_ASSOCIATION_COPY_NONATOMIC); [self addTarget:self action:@selector(callActionBlock:) forControlEvents:event]; } - (void)callActionBlock:(id)sender { ActionBlock block = (ActionBlock)objc_getAssociatedObject(self, &overviewKey); if (block) { block(); } } @end
操作:
[button handleControlEvent:UIControlEventTouchUpInside withBlock:^{
NSLog(@"ssss : %@", self.paramDic);
}];