Objective C: Image not displayed correctly in UIBarButtonItem

I have created a new image to be included in a barbutton item as seen below

However, when I try to add the image to the UIBarButtonItem (as seen in code below)

UIBarButtonItem *newQuestionButton = [[UIBarButtonItem alloc]initWithImage:[UIImage imageNamed:@"doneButton_text"] style:UIBarButtonItemStyleBordered target:self action:@selector(displayNewQuestion)];

I get the following result

What can I do to display the actual color of the text in the original image in the barb开发者_运维问答utton?

The reason why it shows as white is because only alpha values in the image are used to create the bar button image. Whatever image you provide is converted into a image with shades of white, based on the alpha values. The image must be modified to conform to the iOS Human Interface Guidelines:

1. Use the PNG format.
2. Use pure white with appropriate alpha.
3. Do not include a drop shadow.
4. Use anti-aliasing.
5. If you decide to add a bevel, be sure that it is 90° (to help you do this, imagine a light source positioned at the top of the icon).
6. For toolbar and navigation bar icons, create an icon that measures about 20 x 20 pixels.
7. For tab bar icons, create an icon that measures about 30 x 30 pixels.

You can find the docs here:

Human Interface Guidelines