How do I get red green blue (RGB) and alpha back from a UIColor object?
cocoa-touch, iphone, objective-c, rgb, uicolor
Solution
The reason for the crash when accessing `SelectedColor.CGColor` could be that you do not retain the result from `getColor`, perhaps what you need is:
SelectedColor = [[(ColorPickerView *)alertView getColor] retain];
You can only get the RGB color component from a `UIColor` that is using the RGB color space, since you are using `colorWithRed:green:blue:alpha:` that is not a problem, but be vary of this if your code changes.
With this is mind getting the color components is really easy:
const CGFloat* components = CGColorGetComponents(SelectedColor.CGColor);
NSLog(@"Red: %f", components[0]);
NSLog(@"Green: %f", components[1]);
NSLog(@"Blue: %f", components[2]);
NSLog(@"Alpha: %f", CGColorGetAlpha(SelectedColor.CGColor));
Problem
I am getting a UIColor returned from this method: ``` - (UIColor *)getUserSelectedColor { return [UIColor colorWithRed:redSlider.value green:greenSlider.value blue:blueSlider.value alpha:1.0]; } ``` and getting color like this: ``` UIColor *selectedColor = [(ColorPickerView *)alertView getUserSelectedColor]; ``` Now I want to get red, green, blue from selectedColor, in order to use those values. I want values between 0 and 1.