Icon blur of uitabbar

Original article Excerpted from:Http://blog.sina.com.cn/s/blog_8988732e0100xdnq.html

Recently, I encountered a problem during the project development process. It was very painful-The uitabbar custom icon was blurred, and the size was 34*33 at the beginning, which was too big, then I checked it on the official website. It was 30*30. However, it is strange that the icon of this size is used. When the uitabbar option is selected, the icon edge is blurred:

  

 At first, I suspected the problem of the size. I tried all the sizes and then tried various colors. The result was also fuzzy. I checked a lot of information on the Internet and couldn't solve the problem. Today, I accidentally discovered the truth. It is actually very simple. This involves the mechanism of the IOS system.Each uitabbar icon requires two types of images: a gray or black background, 30*30 or so, a pure white background, and 30*30*60*60. For example:    When the image name is used, the first image name is name.png, and the second image name is name@2x.png. (Note that all images are punctuation marks and lowercase letters X are used ),The icons displayed on uitabbar' will change with the name@2x.png Icon size. We do not know the background of this mechanism yet.

 After this setting, the icon is clear and the effect is as follows: