iOS颜色转换成图片的方法

 //  颜色转换为背景图片
 - (UIImage *)imageWithColor:(UIColor *)color {
     CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
     UIGraphicsBeginImageContext(rect.size);
     CGContextRef context = UIGraphicsGetCurrentContext();

     CGContextSetFillColorWithColor(context, [color CGColor]);
     CGContextFillRect(context, rect);

     UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
     UIGraphicsEndImageContext();

     return image;
 }

使用例子

 - (void)viewDidLoad {
     [super viewDidLoad];

     UIButton *button1 = [[UIButton alloc] initWithFrame:CGRectMake(, , , )];
     [button1 setTitle:@"button1" forState:UIControlStateNormal];
     button1.backgroundColor = [UIColor orangeColor];
     [button1 addTarget:self action:@selector(button1BackGroundHighlighted:) forControlEvents:UIControlEventTouchDown];
     [button1 addTarget:self action:@selector(button1BackGroundNormal:) forControlEvents:UIControlEventTouchUpInside];
     [self.view addSubview:button1];

     UIButton *button2 = [[UIButton alloc] initWithFrame:CGRectMake(, , , )];
     [button2 setTitle:@"button2" forState:UIControlStateNormal];
     [button2 setBackgroundImage:[self imageWithColor:[UIColor redColor]] forState:UIControlStateNormal];
     [button2 setBackgroundImage:[self imageWithColor:[UIColor grayColor]] forState:UIControlStateHighlighted];
     [self.view addSubview:button2];
 }

效果如下图：