看不懂Event Handling Guide for iOS－Interacting with Other User Interface Controls里的表达方式
如果您有这些控件之一的自定义子类并且想要更改 >default 操作，请将手势识别器直接附加到控件而不是 > 父视图。然后，手势识别器首先接收到触摸事件。
谁能给我一些例子？谢谢
【问题讨论】：
子类UIButton 附加手势识别器。
在 CustomButton.m 中
#import "CustomButton.h"
@implementation CustomButton
- (instancetype)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc]
initWithTarget:self action:@selector(handleTap)];
tapGesture.numberOfTapsRequired = 2;
[self addGestureRecognizer:tapGesture];
}
return self;
}
- (void)handleTap
{
NSLog(@"Button tapped twice");
}
在您的 ViewController 中启动按钮并添加为子视图
#import "ViewController.h"
#import "CustomButton.h"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
CustomButton *customButton = [[CustomButton alloc] initWithFrame:CGRectMake(100.0f, 100.0f, 150.0f, 100.0f)];
[customButton setTitle:@"Tap Twice" forState:UIControlStateNormal];
customButton.backgroundColor = [UIColor grayColor];
[self.view addSubview:customButton];
}
通常按钮在单击时工作。我们正在通过将点击手势识别器和点击次数增加 2 来更改按钮的默认行为。
【讨论】：