自定義Button背景色的方法

//自定義button設置背景色的方法

- (void)setBackgroundColor:(UIColor *)color forState:(UIControlState)state{
    [self setBackgroundImage:[self buttonImageFromColor:color] forState:state];
}

- (UIImage *) buttonImageFromColor:(UIColor *)color {
    CGRect rect = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}