不用interface　builder　怎样将事件跟按钮关联起来？

就是用代码新建一个按钮，然后与一个IBAction事件关联起来运行可以看到按钮，点击按钮会执行一个事件函数　具体如何做的，书本没教，都是ib连接的

[button addTarget:self action:@selector(函数名) forControlEvents:UIControlEventTouchUpInside];
midButton= [[UIButton alloc] initWithFrame:CGRectMake(349, 387,90,90)];
[midButton setImage:[UIImage imageNamed:@"arge.png"] forState:UIControlStateNormal];
[midButton addTarget:self action:@selector(showImage) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:midButton];
midButton.tag = 8;
[midButton autorelease];
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-(void)showImage{}