UIButton相关的知识点

链接地址：http://blog.sina.com.cn/s/blog_793f11ce0100teyj.html

在viewDidLoad 事件中绘制

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.

- (void)viewDidLoad {

    [super viewDidLoad];

//绘制按钮

UIButton *btn=[UIButton buttonWithType:UIButtonTypeRoundedRect]; //绘制形状

//确定宽、高、X、Y坐标

CGRect frame;

frame.size.width=100;

frame.size.height=30;

frame.origin.x=320/2-50;

frame.origin.y=480/2-30;

[btn setFrame:frame];

//设置Tag(整形)

btn.tag=0;

//设置标题

[btn setTitle:@"按钮" forState:UIControlStateNormal];

//设置未按下和按下的图片切换

[btn setBackgroundImage:[UIImage imageNamed:@"bus.png"] forState:UIControlStateNormal];

[btn setBackgroundImage:[UIImage imageNamed:@"plane.png"] forState:UIControlStateHighlighted];

//设置事件

[btn addTarget:self action:@selector(btnPressed:) forControlEvents:UIControlEventTouchUpInside];

//设置背景色和透明度

//[btn setBackgroundColor:[UIColor blackColor]];

//[btn setAlpha:0.8];

[self.view addSubview:btn];

//[btn release];

}

//按钮响应事件

-(void) btnPressed:(id) sender{

UIButton *myBtn=(UIButton *) sender;

if (myBtn.tag==0) {

//预留模块

}

}