做项目封装UIView的时候碰到的问题，没想到有个哥们儿还写成博客，特此收藏！
问题是这样的，几个界面用到同一个自定义返回按钮，于是就想着把这个按钮单独封装起来，添加一个UIView类，在里面自定义UIButton，使用delegate来实现点击事件
//UIView类头文件XZXTopView.h
#import <UIKit/UIKit.h>
@protocol BtnDelegate <NSObject> //定义一个delegate
- (void)dismissViewController; //声明一个delegate方法
@end
@interface XZXTopView : UIView{
id <BtnDelegate> delegate; //声明delegate变量
}
@property (nonatomic, strong) id <BtnDelegate> delegate; //声明delegate属性
@end
//UIView类XZXTopView.m
#import "XZXTopView.h"
@implementation XZXTopView
@synthesize delegate;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
//自定义一个UIButton
UIButton *button=[UIButtonbuttonWithType:UIButtonTypeCustom];
UIImage *image = [UIImage imageNamed:@"b_back"];
[button setImage:image forState:UIControlStateNormal];
[button setFrame:CGRectMake(5., 7., image.size.width, image.size.height)];
[button addTarget:selfaction:@selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:button];
}
return self;
}
- (void)buttonClicked:(UIButton *)sender{
[delegate dismissViewController]; //点击按钮执行此delegate方法
}
//UIViewController类头文件XZXHelpViewController.h
#import <UIKit/UIKit.h>
#import "XZXTopView.h"
@interface XZXHelpViewController : UIViewController<BtnDelegate> //这里
@end
//UIViewController类 XZXHelpViewController.m文件
#import "XZXHelpViewController.h"
@interfaceXZXHelpViewController ()
@end
@implementation XZXHelpViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
returnself;
}
- (void)viewDidLoad
{
[superviewDidLoad];
// Do any additional setup after loading the view from its nib.
XZXTopView *topView = [[XZXTopView alloc] init]; //错误的初始化
topView.delegate = self; //定义XZXTopView的时候指定其代理为自身
[self.view addSubview:topView];
}
- (void)didReceiveMemoryWarning
{
[superdidReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
//点击button后的具体执行方法
- (void)dismissViewController
{
[selfdismissViewControllerAnimated:YES completion:NULL];
}
@end
代理简单的用法就是这样
上述代码编译执行后，按钮正常显示，但点击没有反应，这是为什么呢？
受惯性思维影响，认为既然能显示，就点击的到，实际上按钮并没有被真正点击到，那是因为我们并没有设置UIButton的上一层UIView类的frame，即
XZXTopView *topView = [[XZXTopView alloc] init]; 这样的初始化是错误的
这样初始化后topView的frame是默认的（0.0，0.0，0.0，0.0）；使得button并没有被点击到
正确的初始化方法：
XZXTopView *topView = [[XZXTopView alloc] initWithFrame:CGRectMake(0.0,0.0,320,50)]; //frame自己设置，比button大就可以了
或者在XZXTopView里把自身的frame也可以
转自：http://www.haogongju.net/art/2043183