KHTabPagerViewController

Introduction

This is a slightly tweaked implementation for the tab pager view controller. It's heavily based on guilhermearaujo/GUITabPagerViewController

Added Features

1. Support for progressive scrolling.
2. Support for a custom view to be drawn above the tab bar. This is particularly handy if you need to present more controls based upon the child view controllers.
3. Now with full RTL UI mirroring support (for Arabic localization) for both iOS 9 new APIs and the older iOS 8 and earlier.

Progressive Scrolling

This is a side-by-side comparison between the progressive and non-progressive scrolling behavior.

Progressive (on the left) tracks the touch movement to update the tab bar accordingly.

Non-progressive (on the right) snaps to the next tab once the touch starts moving.

Installation

CocoaPods (recommended)
Add the following line to your Podfile:
pod 'KHTabPagerViewController', '~> 1.0.0'
And then add #import <KHTabPagerViewController.h> to your view controller.

Manual
Copy the folder KHTabPagerViewController to your project, then add #import "KHTabPagerViewController.h" to your view controller.

Usage

To use it, you should create a view controller that extends KHTabPagerViewController. Write your viewDidLoad as follows:

- (void)viewDidLoad {
  [super viewDidLoad];
  [self setDataSource:self];
}

- (void)viewWillAppear:(BOOL)animated {
  [super viewWillAppear:animated];
  [self reloadData]; 
  }

Then, implement the KHTabPagerDataSource to populate the view. The data source has a couple of required methods, and a few more optional.

Data Source

The data source methods will allow you to provide content to your tab pager view controller.

Required Methods

- (NSInteger)numberOfViewControllers;
- (UIViewController *)viewControllerForIndex:(NSInteger)index;

Optional Methods

Note that despite being optional, the tab setup will require you to return either a UIView or an NSString to work.

- (UIView *)viewForTabAtIndex:(NSInteger)index;
- (NSString *)titleForTabAtIndex:(NSInteger)index;
- (CGFloat)tabHeight;  // Default value: 44.0f
- (UIColor *)tabColor; // Default value: [UIColor orangeColor]
- (UIColor *)tabBackgroundColor; // Default: [UIColor colorWithWhite:0.95f alpha:1.0f];
- (UIFont *)titleFont; // Default: [UIFont fontWithName:@"HelveticaNeue-Thin" size:20.0f];
- (UIColor *)titleColor; // Default: [UIColor blackColor];
- (CGFloat)tabBarTopViewHeight; //Default value: 0.0f
- (UIView *)tabBarTopView;  //Default: nil
- (BOOL)isProgressiveTabBar; //Default value: YES

Delegate

The delegate methods report events that happened in the tab pager view controller.

Optional Methods

- (void)tabPager:(GUITabPagerViewController *)tabPager willTransitionToTabAtIndex:(NSInteger)index;
- (void)tabPager:(GUITabPagerViewController *)tabPager didTransitionToTabAtIndex:(NSInteger)index;

Public Methods

- (void)reloadData;
- (NSInteger)selectedIndex;
- (void)selectTabbarIndex:(NSInteger)index animation:(BOOL)animation;

reloadData will refresh the content of the tab pager view controller. Make sure to provide the data source before reloading the content.

selectedIndex will return the index of the current selected tab.

selectTabbarIndex:animation: will change to selected view controller programatically