Enhanced PrettyTabBar

[echoz]

This is a huge ass commit. Really sorry for the multiple commits. Should've rebased it first.

That aside, this pull request basically is about an enhanced UITabBar. It has the following features,

1. Shadows that can be configured to appear upwards or downwards
2. Switchable representation of the buttons that appear in the TabBar either between the Apple defaults (UITabBarButton) or the PrettyKit highly configurable version (PrettyTabBarButton)

This new TabBar is should be a drop in replacement while supporting all callbacks that is expected of a UITabBar. Has been tested with UITabBarControllers to work perfectly. No changes needed to make this work with existing projects, just use PrettyTabBar instead of an UITabBar.

The new class PrettyTabBarButton itself provides more configuration than previously possible for normal UITabBars while still support iOS 4.3.

Some of the configurable options include,

• Title font
• Title shadow offset and opacity
• Title color
• Badge border color
• Badge font
• Badge text color
• Badge inner gradient start and end colors
• Image to use for the highlight in the select state or;
• Gradient start and end colors for the highlight in select state
• Badge shadow offset and opacity
• Image to use when the button is selected or;
• Gradient start and end colors for the "tint" on the image to use when button is selected

While these options are configurable on the TabBarButton, they are really only settable via usage of the PrettyTabBar as there is tight coupling between both classes (also how Apple seems to do it).

PrettyTabBarButton draws everything using Core Graphics.

Also added some new methods to the PrettyDrawing class.

[vicpenap]

Done!

I can't make badges work, though :/

[echoz]

Weird. I've gotten them to work by modifying the View Controller's UITabBarItem's badgeValue.

PrettyTabBar listens for changes to those and changes the value accordingly.

[vicpenap]

I've tried, before my changes, that way and also through the IB's field, and it didn't seem to work :/. I haven't tried hard, though.

[echoz]

Weird. Works for me.

Insert this at line 34 of the appdelegate:
((UIViewController *)[self.tabBarController.viewControllers objectAtIndex:0]).tabBarItem.badgeValue = @"1";

[vicpenap]

I did that from the view controller (self.tabBarItem), that's why it didn't work for me.

[echoz]

Ah! Okay. I think I know what to do for this. :)

[echoz]

i just checked apple's implementation, it also doesn't seem to reflect the change in the badge value.

Further investigation says that if you try to set the badgeValue during viewDidLoad, it doesn't seem to work. However anytime else after the UIViewController has loaded, calling self.tabBarItem.badgeValue = something should work fine and update the tabbar.

[echoz]

Regarding #13:

Translucent tabbars would only probably work if they are not part of the UITabBarController as the content view of the tabbar controller will not resize to encompass the area lost (a la translucent UINavigationBar).

Don't really see a point beyond the fact that this might introduce bad UI design.

Btw, added some more commits previously. Not sure if you've merged them.

[vicpenap]

I've just merged them.

[vicpenap]

Hi @echoz. Happy to see tabbar is still alive :D. Do you have any clue about the issue with predefined IB buttons? I mean this: #12 (comment).

[echoz]

I can't give a definitive answer (because I haven't really had the time to look into it), but as of this moment I don't think its possible to use predefined buttons for this :/

[vicpenap]

Well, as a last resort we could add a note in documentation to explain that.

[echoz]

Yeah. I guess that'll do for now. Will look into it when I have more time on my hands.