Question

I'm trying to recreate the look of a UINavigationBar. The background of the bar is drawn using a gradient, but it's unclear exactly what the default colors and points are in it. Has anyone done anything in this area?

Was it helpful?

Solution

From one of my projects. Adjust the colors to your liking. It also can show a background image if you want (imageReady), else it draws the navbar like Apple's

//                                  #Lighter r,g,b,a            #Darker r,g,b,a
#define MAIN_COLOR_COMPONENTS       { 0.153, 0.306, 0.553, 1.0, 0.122, 0.247, 0.482, 1.0 }
#define LIGHT_COLOR_COMPONENTS      { 0.478, 0.573, 0.725, 1.0, 0.216, 0.357, 0.584, 1.0 }

@implementation UINavigationBar (UINavigationBarCategory)

- (void)drawRect:(CGRect)rect {
    if (imageReady) {
        UIImage *img = [UIImage imageNamed: @"navigation_background.png"];
        [img drawInRect:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
    } else {
        // Render yourself instead.
        // You will need to adjust the MAIN_COLOR_COMPONENTS and LIGHT_COLOR_COMPONENTS to match your app

       // emulate the tint colored bar
       CGContextRef context = UIGraphicsGetCurrentContext();
       CGFloat locations[2] = { 0.0, 1.0 };
       CGColorSpaceRef myColorspace = CGColorSpaceCreateDeviceRGB();

       CGFloat topComponents[8] = LIGHT_COLOR_COMPONENTS;
       CGGradientRef topGradient = CGGradientCreateWithColorComponents(myColorspace, topComponents, locations, 2);
       CGContextDrawLinearGradient(context, topGradient, CGPointMake(0, 0), CGPointMake(0,self.frame.size.height/2), 0);
       CGGradientRelease(topGradient);

       CGFloat botComponents[8] = MAIN_COLOR_COMPONENTS;
       CGGradientRef botGradient = CGGradientCreateWithColorComponents(myColorspace, botComponents, locations, 2);
       CGContextDrawLinearGradient(context, botGradient,
       CGPointMake(0,self.frame.size.height/2), CGPointMake(0, self.frame.size.height), 0);
       CGGradientRelease(botGradient);

       CGColorSpaceRelease(myColorspace);


       // top Line
       CGContextSetRGBStrokeColor(context, 1, 1, 1, 1.0);
       CGContextMoveToPoint(context, 0, 0);
       CGContextAddLineToPoint(context, self.frame.size.width, 0);
       CGContextStrokePath(context);

       // bottom line
       CGContextSetRGBStrokeColor(context, 0, 0, 0, 1.0);
       CGContextMoveToPoint(context, 0, self.frame.size.height);
       CGContextAddLineToPoint(context, self.frame.size.width, self.frame.size.height);
       CGContextStrokePath(context);
    }
}

@end
Licensed under: CC-BY-SA with attribution
Not affiliated with StackOverflow
scroll top