问题
I have created .png icons 20 x 20 and when I set the image property in the nib they just appear grey blocks.
Any ideas?
UPDATE: Here is one of the icons!
回答1:
The standard tabbar icons in iOS are rendered solely from the alpha channel. Colors are ignored completely. Instead of colors you can use different alpha values that lead to a different shade of gray (or blue if selected)
Make the background of your icons transparent.
回答2:
Download these attached images and pass them to your designer and ask him to just create images like these (when you open them in PS you'll know the difference)
回答3:
This happened to me in iOS 5, I got around it by setting UIImage Outlet property in the Xib to 'Custom' and then set the label programmtically so : imageOne = [UIImage imageNames@"Dog.png"];
回答4:
Try saving the file as png interlaced. In photoshop at least it gives you an option of interlaced or normal.
来源：https://stackoverflow.com/questions/8616820/uitabbaritem-images-just-appear-as-a-grey-block