How to customize iPhone UITabBarController selected icon, background?

In the UITabBarController I have implemented.. (the standard one).. when an item开发者_Python百科 is selected, it has an opaque grey square background behind the item. Is there a way to change the colour and opacity of that square?

Would prefer if I don't have to use an external API or hack.

Thanks!

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From what I know, there is no documented way of changing view properties of UITabBar, without doing some kind of hacks like subclassing UITabBar and putting colorful top layer that would became a tint . You will most likely need to create your own tab bar using UIButtons.