UITabBar only shows Black/Blue Square Place holder like image, what could be a potential reason?

Question

I am now adapting @1x, @2x, @3x for different iPhone screens sizes. And this problem come to puzzle me:

Code I'm using:

UITabBarItem *item = [[UITabBarItem alloc] initWithTitle:@"Home" image:[UIImage imageNamed:@"tabbar_circle"]  selectedImage:[UIImage imageNamed:@"tabbar_circle_blue"]];
_circleNavController.tabBarItem = item;

Instead showing some images that make sense, it only shows a placeholder with blue/black square, I am sure the image names are correct since a wrong name will return to an empty area.

Blue Square Placeholder

Answer 1

UITabBarItem *item = [[UITabBarItem alloc] initWithTitle:@"Home" image:[[UIImage imageNamed:@"tabbar_circle"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]
                                                   selectedImage:[[UIImage imageNamed:@"tabbar_circle_blue"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]
                              ];

Finally got this solution, enlighten by @matt