比如

- 设置tabBarItem的选中图片

vc.tabBarItem.selectedImage = image;

- 设置UIButtonTypeSystem样式按钮的image时

UIButton *btn = [UIButton buttonWithType:UIButtonTypeSystem];

[btn setImage:image forState:UIControlStateNormal];

 解决方案

- 再次产生一张不会进行渲染的图片

// 加载图片

UIImage *tempImage = [UIImage imageNamed:@"tabBar_essence_click_icon"];

// 产生一张不会进行自动渲染的图片

UIImage *selectedImage = [tempImage imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

vc.tabBarItem.selectedImage = selectedImage;