UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(0, 100, 200, 100)];    //添加点击事件  [button addTarget:self action:@selector(pushToSecond) forControlEvents:UIControlEventTouchUpInside];    //整个按钮的背景色（无背景图片时有效果）  button.backgroundColor = [UIColor greenColor];    //添加背景图片  [button setBackgroundImage:[UIImage imageNamed:@"01.png"] forState:UIControlStateNormal];    //按钮标题  [button setTitle:@"Hello World!" forState:UIControlStateNormal];    //button上子控件的水平对齐方式  button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;    //button上子控件的垂直对齐方式  button.contentVerticalAlignment = UIControlContentVerticalAlignmentTop;    //内容容器的偏移，让文字向右偏移20像素  button.contentEdgeInsets = UIEdgeInsetsMake(0,20, 0, 0);    //设置标题的背景颜色  button.titleLabel.backgroundColor = [UIColor purpleColor];    //标题颜色  [button setTitleColor:[UIColor yellowColor]forState:UIControlStateNormal];    button.imageView.contentMode = UIViewContentModeScaleAspectFit;    [self.view addSubview:button];  [button release];

改变UIButton上标题位置、文字颜色、背景色等