iOS 原生的 UIButton 点击事件是不允许带多参数的,唯一的一个参数就是默认UIButton本身
那么我们该怎么实现传递多个参数的点击事件呢?
1.如果业务场景非常简单,要求传单参数并且是整数类型,可以用tag
[cell.deleteButton setTag:indexPath.row]; //例如,将cell的行数设置成tag
2.利用ObjC关联,runtime之所以被称为iOS 的动态特性是有道理的,当然关联甚至可以帮助NSArray等其他对象实现“多参数传递”
实现起来也非常简便:
UIButton *btn = // create the button objc_setAssociatedObject(btn, "firstObject", someObject, OBJC_ASSOCIATION_RETAIN_NONATOMIC); //实际上就是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"); //取参 id second = objc_setAssociatedObject(btn, "secondObject"); // etc. }
3.利用自定义,添加一个多参数的字典属性变量即可(为什么要字典?可以装多多的)
自定义Button子类,甚至都不用重写啥的:
@interface MultiParamButton : UIButton @property (nonatomic, strong) NSDictionary* multiParamDic; @end
传参:
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;
点击:
- (void)multiParamButtonClicked:(UIButton* )button { MultiParamButton* multiParamButton = (MultiParamButton* )button; NSLog(@"Vvvverify : %@", multiParamButton.multiParamDic); }
爽爽的:
当然,如果用扩展,然后添加property后重写GetSet也是一样一样的
4.完全不在Button上入手,针对业务来,最常见的就是在TableViewCell上面的Button,这种存在(视图)继承树之间的传递,这里举个简单的例子
Button获取所属父视图的所属视图控制器的参数,间接传参
#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; //获取button所属的视图控制器,如果视图控制器都能获取,还有什么不能获取呢? 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
这种非常多的用在UITableViewCell上自定义的按钮的参数的情况!
5.利用Delegate和performSelector:withObject:withObject 方法可以传递最多两个参数:
定义protocol:
#pragma mark - SYAccountListCellDelegate. @class SYAccountListCell; @protocol SYAccountListCellDelegate- (void)accountListCell:(SYAccountListCell* )cell didTapButton:(UIButton* )button; @end
自定义Cell的时候将你想传的东西传进入,这里用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]; } } @end
Delegate实现:
#pragma mark - SYAccountListCellDelegate. - (void)accountListCell:(SYAccountListCell *)cell didTapButton:(UIButton *)button { NSLog(@"Cell : %@ , Button : %@", cell, button); }
虽然有点曲折,但是传参效果非常到位
这里补充一下,这里的最多两个参数是直面的参数个数,如果将参数设置位结构体,那么就皆大欢喜啦,想怎么传就怎么传!
6.利用Block 和 关联 , 直接可以当前点击并且操作参数 - 强!
#importtypedef void (^ActionBlock)(); @interface UIButton (Utility) @property (readonly) NSMutableDictionary *event; - (void) handleControlEvent:(UIControlEvents)controlEvent withBlock:(ActionBlock)action; @end
实现文件:
#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); }];