├── Podfile
├── BKSlidingViewController.xcodeproj
    ├── project.xcworkspace
    │   ├── contents.xcworkspacedata
    │   └── xcshareddata
    │   │   └── BKSlidingViewController.xccheckout
    └── project.pbxproj
├── BKSlidingViewController.xcworkspace
    ├── contents.xcworkspacedata
    └── xcshareddata
    │   └── BKSlidingViewController.xccheckout
├── BKSlidingViewController
    ├── UIViewController+BKTag.h
    ├── UIViewController+BKTag.m
    ├── BKSlidingViewController.h
    ├── BKSlidingViewController_Extras.h
    └── BKSlidingViewController.m
├── README.md
├── LICENSE
├── BKSlidingViewController.podspec
└── .gitignore


/Podfile:
--------------------------------------------------------------------------------
1 | source 'https://github.com/CocoaPods/Specs.git'
2 | platform :ios, '7.0'
3 | 
4 | pod 'BKSlidingViewController', :path => '.'
5 | 


--------------------------------------------------------------------------------
/BKSlidingViewController.xcodeproj/project.xcworkspace/contents.xcworkspacedata:
--------------------------------------------------------------------------------
1 | <?xml version="1.0" encoding="UTF-8"?>
2 | <Workspace
3 |    version = "1.0">
4 |    <FileRef
5 |       location = "self:BKSlidingViewController.xcodeproj">
6 |    </FileRef>
7 | </Workspace>
8 | 


--------------------------------------------------------------------------------
/BKSlidingViewController.xcworkspace/contents.xcworkspacedata:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="UTF-8"?>
 2 | <Workspace
 3 |    version = "1.0">
 4 |    <FileRef
 5 |       location = "group:BKSlidingViewController.xcodeproj">
 6 |    </FileRef>
 7 |    <FileRef
 8 |       location = "group:Pods/Pods.xcodeproj">
 9 |    </FileRef>
10 | </Workspace>
11 | 


--------------------------------------------------------------------------------
/BKSlidingViewController/UIViewController+BKTag.h:
--------------------------------------------------------------------------------
 1 | // Copyright 2014-present 650 Industries.
 2 | 
 3 | @import UIKit;
 4 | 
 5 | /**
 6 |  Attach `NSInteger` tags to `UIViewController` classes.
 7 |  */
 8 | @interface UIViewController (BKTag)
 9 | 
10 | /**
11 |  An integer that you can use to identify view controllers in your application.
12 |  
13 |  @discussion The default value is 0. You can set the value of this tag and use that value to identify the view controller later.
14 |  */
15 | @property (nonatomic, assign, setter=bk_setTag:, getter=bk_tag) NSInteger bk_tag;
16 | 
17 | @end
18 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | # BKSlidingViewController
 2 | 
 3 | A side-scrolling view controller container class with a minimal, UITabBarController-like API.
 4 | 
 5 | ## Installation
 6 | 
 7 | 1. Add BKSlidingViewController to your Podfile.
 8 | 2. In your terminal, run `pod install`.
 9 | 
10 | ## Usage
11 | 
12 | 1. Add `#import <BKSlidingViewController/BKSlidingViewController.h>` to your application delegate class.
13 | 2. In your `application:didFinishLaunchingWithOptions:` method, create and configure an instance of `BKSlidingViewController` with your desired view controllers and initial selected index.
14 | 3. Set the `rootViewController` property on your `UIWindow` to your instance of `BKSlidingViewController`.
15 | 


--------------------------------------------------------------------------------
/BKSlidingViewController/UIViewController+BKTag.m:
--------------------------------------------------------------------------------
 1 | // Copyright 2014-present 650 Industries.
 2 | 
 3 | #import "UIViewController+BKTag.h"
 4 | 
 5 | @import ObjectiveC;
 6 | 
 7 | static const void *UIViewControllerBKTagKey = "UIViewControllerBKTagKey";
 8 | 
 9 | @implementation UIViewController (BKTag)
10 | 
11 | - (void)bk_setTag:(NSInteger)tag
12 | {
13 |     NSNumber *value = [NSNumber numberWithInteger:tag];
14 |     objc_setAssociatedObject(self, UIViewControllerBKTagKey, value, OBJC_ASSOCIATION_COPY_NONATOMIC);
15 | }
16 | 
17 | - (NSInteger)bk_tag
18 | {
19 |     NSNumber *value = objc_getAssociatedObject(self, UIViewControllerBKTagKey);
20 |     if (value) {
21 |         return [value integerValue];
22 |     } else {
23 |         return 0;
24 |     }
25 | }
26 | 
27 | @end
28 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
 1 | The MIT License (MIT)
 2 | 
 3 | Copyright (c) 2014 650 Industries, Inc.
 4 | 
 5 | Permission is hereby granted, free of charge, to any person obtaining a copy
 6 | of this software and associated documentation files (the "Software"), to deal
 7 | in the Software without restriction, including without limitation the rights
 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 9 | copies of the Software, and to permit persons to whom the Software is
10 | furnished to do so, subject to the following conditions:
11 | 
12 | The above copyright notice and this permission notice shall be included in
13 | all copies or substantial portions of the Software.
14 | 
15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
21 | THE SOFTWARE.
22 | 


--------------------------------------------------------------------------------
/BKSlidingViewController.podspec:
--------------------------------------------------------------------------------
 1 | Pod::Spec.new do |s|
 2 |   s.name             = "BKSlidingViewController"
 3 |   s.version          = "1.1.0"
 4 |   s.summary          = "A side-scrolling view controller container class with a minimal, UITabBarController-like API."
 5 |   s.description      = <<-DESC
 6 |                        UIPageViewController seems somewhat rigidly designed for paginated content, and is very efficient at lazily instantiating many view controllers with a particular pattern (before/after) and specific spatial metaphors. While it can do many things well, customization is ultimately limited by permissible alterations of the UIPageViewController class.
 7 | 
 8 |                        BKSlidingViewController is an open-source substitute for applications desiring view controllers laid out horizontally, presented with a UITabBarController-like API.
 9 |                        DESC
10 |   s.homepage         = "https://github.com/Basket/BKSlidingViewController"
11 |   s.license          = 'MIT'
12 |   s.author           = { "Andrew Toulouse" => "andrew@atoulou.se" }
13 |   s.source           = { :git => "https://github.com/Basket/BKSlidingViewController.git", :tag => s.version.to_s }
14 | 
15 |   s.platform     = :ios, '7.0'
16 |   s.requires_arc = true
17 | 
18 |   s.dependency 'BKDeltaCalculator', '~> 1.0'
19 | 
20 |   s.source_files = 'BKSlidingViewController/*.{h,m}'
21 |   s.frameworks = 'UIKit'
22 | end
23 | 


--------------------------------------------------------------------------------
/BKSlidingViewController/BKSlidingViewController.h:
--------------------------------------------------------------------------------
 1 | // Copyright 2014-present 650 Industries.
 2 | 
 3 | @import UIKit;
 4 | 
 5 | /**
 6 |  `BKSlidingViewController` is a container view controller designed to slide view controllers in a scroll view, and to do
 7 |  so with an API mimicking that of `UITabBarController`.
 8 |  
 9 |  `BKSlidingViewController` methods may be called from within UIView animation blocks.
10 |  */
11 | @interface BKSlidingViewController : UIViewController
12 | 
13 | // These are designed to respect their animation context's duration. Call them from an animation
14 | // block if so desired.
15 | 
16 | /**
17 |  The view controllers displayed by the sliding view controller.
18 |  */
19 | @property (nonatomic, copy) NSArray *viewControllers;
20 | 
21 | /**
22 |  The view controller being shown by the sliding view controller.
23 |  */
24 | @property (nonatomic, weak) UIViewController *selectedViewController;
25 | 
26 | /**
27 |  The index of the view controller being shown by the sliding view controller.
28 |  */
29 | @property (nonatomic, assign) NSInteger selectedIndex;
30 | 
31 | /**
32 |  The view controller in the sliding view controller assigned the given tag.
33 |  
34 |  @param tag The tag for the desired view controller.
35 |  @return the first UIViewController whose tag matches.
36 |  */
37 | - (UIViewController *)viewControllerWithTag:(NSInteger)tag;
38 | 
39 | /**
40 |  The index of the view controller in the sliding view controller assigned the given tag.
41 | 
42 |  @param tag The tag for the desired view controller index.
43 |  @return the first index whose UIViewController's tag matches.
44 |  */
45 | - (NSInteger)indexWithTag:(NSInteger)tag;
46 | 
47 | @end
48 | 


--------------------------------------------------------------------------------
/BKSlidingViewController.xcworkspace/xcshareddata/BKSlidingViewController.xccheckout:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="UTF-8"?>
 2 | <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 3 | <plist version="1.0">
 4 | <dict>
 5 | 	<key>IDESourceControlProjectFavoriteDictionaryKey</key>
 6 | 	<false/>
 7 | 	<key>IDESourceControlProjectIdentifier</key>
 8 | 	<string>ED84C76A-DE3B-4E6C-A10C-6FDDF0B32AD0</string>
 9 | 	<key>IDESourceControlProjectName</key>
10 | 	<string>BKSlidingViewController</string>
11 | 	<key>IDESourceControlProjectOriginsDictionary</key>
12 | 	<dict>
13 | 		<key>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</key>
14 | 		<string>github.com:Basket/BKSlidingViewController.git</string>
15 | 	</dict>
16 | 	<key>IDESourceControlProjectPath</key>
17 | 	<string>BKSlidingViewController.xcworkspace</string>
18 | 	<key>IDESourceControlProjectRelativeInstallPathDictionary</key>
19 | 	<dict>
20 | 		<key>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</key>
21 | 		<string>..</string>
22 | 	</dict>
23 | 	<key>IDESourceControlProjectURL</key>
24 | 	<string>github.com:Basket/BKSlidingViewController.git</string>
25 | 	<key>IDESourceControlProjectVersion</key>
26 | 	<integer>111</integer>
27 | 	<key>IDESourceControlProjectWCCIdentifier</key>
28 | 	<string>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</string>
29 | 	<key>IDESourceControlProjectWCConfigurations</key>
30 | 	<array>
31 | 		<dict>
32 | 			<key>IDESourceControlRepositoryExtensionIdentifierKey</key>
33 | 			<string>public.vcs.git</string>
34 | 			<key>IDESourceControlWCCIdentifierKey</key>
35 | 			<string>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</string>
36 | 			<key>IDESourceControlWCCName</key>
37 | 			<string>BKSlidingViewController</string>
38 | 		</dict>
39 | 	</array>
40 | </dict>
41 | </plist>
42 | 


--------------------------------------------------------------------------------
/BKSlidingViewController/BKSlidingViewController_Extras.h:
--------------------------------------------------------------------------------
 1 | // Copyright 2015-present Andy Toulouse.
 2 | 
 3 | #import "BKSlidingViewController.h"
 4 | 
 5 | @protocol BKSlidingViewControllerDelegate;
 6 | 
 7 | /**
 8 |  Additional functionality for `BKSlidingViewController` beyond its thin `UITabBarController`-like interface.
 9 |  */
10 | @interface BKSlidingViewController ()
11 | 
12 | /**
13 |  Return the amount the sliding view controller has scrolled in the range [0.0, 1.0], with the percentages are defined as:
14 |  
15 |  0%   The first view controller is centered.
16 |  50%  If there is only one view controller, it is centered.
17 |  100% The last view controller is centered.
18 |  */
19 | @property (nonatomic, assign, readonly) CGFloat percentScrolled;
20 | 
21 | /**
22 |  The delegate for the sliding view controller.
23 |  */
24 | @property (nonatomic, weak) id<BKSlidingViewControllerDelegate> delegate;
25 | 
26 | @end
27 | 
28 | /**
29 |  The delegate protocol for the sliding view controller.
30 |  */
31 | @protocol BKSlidingViewControllerDelegate <NSObject>
32 | 
33 | @optional
34 | 
35 | /**
36 |  Called when the sliding view controller will begin dragging. Analogous to the corresponding scrollView method.
37 |  */
38 | - (void)slidingViewControllerWillBeginDragging:(BKSlidingViewController *)slidingViewController;
39 | 
40 | /**
41 |  Called when the sliding view controller scrolls. Analogous to the corresponding scrollView method.
42 |  */
43 | - (void)slidingViewControllerDidScroll:(BKSlidingViewController *)slidingViewController;
44 | 
45 | /**
46 |  Called when the sliding view controller ends decelerating. Analogous to the corresponding scrollView method.
47 |  */
48 | - (void)slidingViewControllerDidEndDecelerating:(BKSlidingViewController *)slidingViewController;
49 | @end


--------------------------------------------------------------------------------
/BKSlidingViewController.xcodeproj/project.xcworkspace/xcshareddata/BKSlidingViewController.xccheckout:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="UTF-8"?>
 2 | <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 3 | <plist version="1.0">
 4 | <dict>
 5 | 	<key>IDESourceControlProjectFavoriteDictionaryKey</key>
 6 | 	<false/>
 7 | 	<key>IDESourceControlProjectIdentifier</key>
 8 | 	<string>9DF40F86-4F48-4E8F-BCEF-F8617E91F6CE</string>
 9 | 	<key>IDESourceControlProjectName</key>
10 | 	<string>BKSlidingViewController</string>
11 | 	<key>IDESourceControlProjectOriginsDictionary</key>
12 | 	<dict>
13 | 		<key>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</key>
14 | 		<string>github.com:Basket/BKSlidingViewController.git</string>
15 | 	</dict>
16 | 	<key>IDESourceControlProjectPath</key>
17 | 	<string>BKSlidingViewController.xcodeproj</string>
18 | 	<key>IDESourceControlProjectRelativeInstallPathDictionary</key>
19 | 	<dict>
20 | 		<key>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</key>
21 | 		<string>../..</string>
22 | 	</dict>
23 | 	<key>IDESourceControlProjectURL</key>
24 | 	<string>github.com:Basket/BKSlidingViewController.git</string>
25 | 	<key>IDESourceControlProjectVersion</key>
26 | 	<integer>111</integer>
27 | 	<key>IDESourceControlProjectWCCIdentifier</key>
28 | 	<string>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</string>
29 | 	<key>IDESourceControlProjectWCConfigurations</key>
30 | 	<array>
31 | 		<dict>
32 | 			<key>IDESourceControlRepositoryExtensionIdentifierKey</key>
33 | 			<string>public.vcs.git</string>
34 | 			<key>IDESourceControlWCCIdentifierKey</key>
35 | 			<string>1B08D3D30C4A91BCCEA949ABBC700BC102BC97AD</string>
36 | 			<key>IDESourceControlWCCName</key>
37 | 			<string>BKSlidingViewController</string>
38 | 		</dict>
39 | 	</array>
40 | </dict>
41 | </plist>
42 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
  1 | #########################
  2 | # .gitignore file for Xcode4 / OS X Source projects
  3 | #
  4 | # Version 2.0
  5 | #    For latest version, see: http://stackoverflow.com/questions/49478/git-ignore-file-for-xcode-projects
  6 | #
  7 | # 2013 updates:
  8 | #    - fixed the broken "save personal Schemes"
  9 | #
 10 | # NB: if you are storing "built" products, this WILL NOT WORK,
 11 | #   and you should use a different .gitignore (or none at all)
 12 | # This file is for SOURCE projects, where there are many extra
 13 | #   files that we want to exclude
 14 | #
 15 | #########################
 16 | 
 17 | #####
 18 | # OS X temporary files that should never be committed
 19 | 
 20 | .DS_Store
 21 | *.swp
 22 | *.lock
 23 | profile
 24 | 
 25 | 
 26 | ####
 27 | # Xcode temporary files that should never be committed
 28 | #
 29 | # NB: NIB/XIB files still exist even on Storyboard projects, so we want this...
 30 | 
 31 | *~.nib
 32 | 
 33 | 
 34 | ####
 35 | # Xcode build files -
 36 | #
 37 | # NB: slash on the end, so we only remove the FOLDER, not any files that were badly named "DerivedData"
 38 | 
 39 | DerivedData/
 40 | 
 41 | # NB: slash on the end, so we only remove the FOLDER, not any files that were badly named "build"
 42 | 
 43 | build/
 44 | 
 45 | 
 46 | #####
 47 | # Xcode private settings (window sizes, bookmarks, breakpoints, custom executables, smart groups)
 48 | #
 49 | # This is complicated:
 50 | #
 51 | # SOMETIMES you need to put this file in version control.
 52 | # Apple designed it poorly - if you use "custom executables", they are
 53 | #  saved in this file.
 54 | # 99% of projects do NOT use those, so they do NOT want to version control this file.
 55 | #  ..but if you're in the 1%, comment out the line "*.pbxuser"
 56 | 
 57 | *.pbxuser
 58 | *.mode1v3
 59 | *.mode2v3
 60 | *.perspectivev3
 61 | #    NB: also, whitelist the default ones, some projects need to use these
 62 | !default.pbxuser
 63 | !default.mode1v3
 64 | !default.mode2v3
 65 | !default.perspectivev3
 66 | 
 67 | 
 68 | ####
 69 | # Xcode 4 - semi-personal settings
 70 | #
 71 | #
 72 | # OPTION 1: ---------------------------------
 73 | #     throw away ALL personal settings (including custom schemes!
 74 | #     - unless they are "shared")
 75 | #
 76 | # NB: this is exclusive with OPTION 2 below
 77 | xcuserdata
 78 | 
 79 | # OPTION 2: ---------------------------------
 80 | #     get rid of ALL personal settings, but KEEP SOME OF THEM
 81 | #     - NB: you must manually uncomment the bits you want to keep
 82 | #
 83 | # NB: this is exclusive with OPTION 1 above
 84 | #
 85 | #xcuserdata/**/*
 86 | 
 87 | #     (requires option 2 above): Personal Schemes
 88 | #
 89 | #!xcuserdata/**/xcschemes/*
 90 | 
 91 | ####
 92 | # XCode 4 workspaces - more detailed
 93 | #
 94 | # Workspaces are important! They are a core feature of Xcode - don't exclude them :)
 95 | #
 96 | # Workspace layout is quite spammy. For reference:
 97 | #
 98 | # /(root)/
 99 | #   /(project-name).xcodeproj/
100 | #     project.pbxproj
101 | #     /project.xcworkspace/
102 | #       contents.xcworkspacedata
103 | #       /xcuserdata/
104 | #         /(your name)/xcuserdatad/
105 | #           UserInterfaceState.xcuserstate
106 | #     /xcsshareddata/
107 | #       /xcschemes/
108 | #         (shared scheme name).xcscheme
109 | #     /xcuserdata/
110 | #       /(your name)/xcuserdatad/
111 | #         (private scheme).xcscheme
112 | #         xcschememanagement.plist
113 | #
114 | #
115 | 
116 | ####
117 | # Xcode 4 - Deprecated classes
118 | #
119 | # Allegedly, if you manually "deprecate" your classes, they get moved here.
120 | #
121 | # We're using source-control, so this is a "feature" that we do not want!
122 | 
123 | *.moved-aside
124 | 
125 | 
126 | ####
127 | # UNKNOWN: recommended by others, but I can't discover what these files are
128 | #
129 | # ...none. Everything is now explained.
130 | 
131 | ####
132 | # CocoaPods
133 | #
134 | # Include Podfile and Podfile.lock but ignore the pods themselves
135 | 
136 | Pods/
137 | 


--------------------------------------------------------------------------------
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 78 | 			name = Products;
 79 | 			sourceTree = "<group>";
 80 | 		};
 81 | 		6BEE0A1319870F5700D73B41 /* BKSlidingViewController */ = {
 82 | 			isa = PBXGroup;
 83 | 			children = (
 84 | 				6BEE0A1419870F5700D73B41 /* BKSlidingViewController.h */,
 85 | 				6BEE0A1619870F5700D73B41 /* BKSlidingViewController.m */,
 86 | 				6BEE0A2C1987100100D73B41 /* UIViewController+BKTag.h */,
 87 | 				6BEE0A2B1987100100D73B41 /* UIViewController+BKTag.m */,
 88 | 			);
 89 | 			path = BKSlidingViewController;
 90 | 			sourceTree = "<group>";
 91 | 		};
 92 | 		7A56D345A85686D265F48F26 /* Frameworks */ = {
 93 | 			isa = PBXGroup;
 94 | 			children = (
 95 | 				49D185DA94EBEB7EEC1ABA50 /* libPods.a */,
 96 | 			);
 97 | 			name = Frameworks;
 98 | 			sourceTree = "<group>";
 99 | 		};
100 | /* End PBXGroup section */
101 | 
102 | /* Begin PBXNativeTarget section */
103 | 		6BEE0A1019870F5700D73B41 /* BKSlidingViewController */ = {
104 | 			isa = PBXNativeTarget;
105 | 			buildConfigurationList = 6BEE0A2519870F5700D73B41 /* Build configuration list for PBXNativeTarget "BKSlidingViewController" */;
106 | 			buildPhases = (
107 | 				850533F88D5B73D818D4C5A2 /* Check Pods Manifest.lock */,
108 | 				6BEE0A0D19870F5700D73B41 /* Sources */,
109 | 				6BEE0A0E19870F5700D73B41 /* Frameworks */,
110 | 				6BEE0A0F19870F5700D73B41 /* CopyFiles */,
111 | 				BBB21D433F36FBB84D7A38CD /* Copy Pods Resources */,
112 | 			);
113 | 			buildRules = (
114 | 			);
115 | 			dependencies = (
116 | 			);
117 | 			name = BKSlidingViewController;
118 | 			productName = BKSlidingViewController;
119 | 			productReference = 6BEE0A1119870F5700D73B41 /* libBKSlidingViewController.a */;
120 | 			productType = "com.apple.product-type.library.static";
121 | 		};
122 | /* End PBXNativeTarget section */
123 | 
124 | /* Begin PBXProject section */
125 | 		6BEE0A0919870F5700D73B41 /* Project object */ = {
126 | 			isa = PBXProject;
127 | 			attributes = {
128 | 				LastUpgradeCheck = 0600;
129 | 				ORGANIZATIONNAME = "650 Industries, Inc.";
130 | 				TargetAttributes = {
131 | 					6BEE0A1019870F5700D73B41 = {
132 | 						CreatedOnToolsVersion = 6.0;
133 | 					};
134 | 				};
135 | 			};
136 | 			buildConfigurationList = 6BEE0A0C19870F5700D73B41 /* Build configuration list for PBXProject "BKSlidingViewController" */;
137 | 			compatibilityVersion = "Xcode 3.2";
138 | 			developmentRegion = English;
139 | 			hasScannedForEncodings = 0;
140 | 			knownRegions = (
141 | 				en,
142 | 			);
143 | 			mainGroup = 6BEE0A0819870F5700D73B41;
144 | 			productRefGroup = 6BEE0A1219870F5700D73B41 /* Products */;
145 | 			projectDirPath = "";
146 | 			projectRoot = "";
147 | 			targets = (
148 | 				6BEE0A1019870F5700D73B41 /* BKSlidingViewController */,
149 | 			);
150 | 		};
151 | /* End PBXProject section */
152 | 
153 | /* Begin PBXShellScriptBuildPhase section */
154 | 		850533F88D5B73D818D4C5A2 /* Check Pods Manifest.lock */ = {
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156 | 			buildActionMask = 2147483647;
157 | 			files = (
158 | 			);
159 | 			inputPaths = (
160 | 			);
161 | 			name = "Check Pods Manifest.lock";
162 | 			outputPaths = (
163 | 			);
164 | 			runOnlyForDeploymentPostprocessing = 0;
165 | 			shellPath = /bin/sh;
166 | 			shellScript = "diff \"${PODS_ROOT}/../Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [[ $? != 0 ]] ; then\n    cat << EOM\nerror: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\nEOM\n    exit 1\nfi\n";
167 | 			showEnvVarsInLog = 0;
168 | 		};
169 | 		BBB21D433F36FBB84D7A38CD /* Copy Pods Resources */ = {
170 | 			isa = PBXShellScriptBuildPhase;
171 | 			buildActionMask = 2147483647;
172 | 			files = (
173 | 			);
174 | 			inputPaths = (
175 | 			);
176 | 			name = "Copy Pods Resources";
177 | 			outputPaths = (
178 | 			);
179 | 			runOnlyForDeploymentPostprocessing = 0;
180 | 			shellPath = /bin/sh;
181 | 			shellScript = "\"${SRCROOT}/Pods/Target Support Files/Pods/Pods-resources.sh\"\n";
182 | 			showEnvVarsInLog = 0;
183 | 		};
184 | /* End PBXShellScriptBuildPhase section */
185 | 
186 | /* Begin PBXSourcesBuildPhase section */
187 | 		6BEE0A0D19870F5700D73B41 /* Sources */ = {
188 | 			isa = PBXSourcesBuildPhase;
189 | 			buildActionMask = 2147483647;
190 | 			files = (
191 | 				6BEE0A1719870F5700D73B41 /* BKSlidingViewController.m in Sources */,
192 | 				6BEE0A2F1987100100D73B41 /* UIViewController+BKTag.m in Sources */,
193 | 			);
194 | 			runOnlyForDeploymentPostprocessing = 0;
195 | 		};
196 | /* End PBXSourcesBuildPhase section */
197 | 
198 | /* Begin XCBuildConfiguration section */
199 | 		6BEE0A2319870F5700D73B41 /* Debug */ = {
200 | 			isa = XCBuildConfiguration;
201 | 			buildSettings = {
202 | 				ALWAYS_SEARCH_USER_PATHS = NO;
203 | 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
204 | 				CLANG_CXX_LIBRARY = "libc++";
205 | 				CLANG_ENABLE_MODULES = YES;
206 | 				CLANG_ENABLE_OBJC_ARC = YES;
207 | 				CLANG_WARN_BOOL_CONVERSION = YES;
208 | 				CLANG_WARN_CONSTANT_CONVERSION = YES;
209 | 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
210 | 				CLANG_WARN_EMPTY_BODY = YES;
211 | 				CLANG_WARN_ENUM_CONVERSION = YES;
212 | 				CLANG_WARN_INT_CONVERSION = YES;
213 | 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
214 | 				CLANG_WARN_UNREACHABLE_CODE = YES;
215 | 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
216 | 				COPY_PHASE_STRIP = NO;
217 | 				ENABLE_STRICT_OBJC_MSGSEND = YES;
218 | 				GCC_C_LANGUAGE_STANDARD = gnu99;
219 | 				GCC_DYNAMIC_NO_PIC = NO;
220 | 				GCC_OPTIMIZATION_LEVEL = 0;
221 | 				GCC_PREPROCESSOR_DEFINITIONS = (
222 | 					"DEBUG=1",
223 | 					"$(inherited)",
224 | 				);
225 | 				GCC_SYMBOLS_PRIVATE_EXTERN = NO;
226 | 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
227 | 				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
228 | 				GCC_WARN_UNDECLARED_SELECTOR = YES;
229 | 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
230 | 				GCC_WARN_UNUSED_FUNCTION = YES;
231 | 				GCC_WARN_UNUSED_VARIABLE = YES;
232 | 				IPHONEOS_DEPLOYMENT_TARGET = 7.0;
233 | 				MTL_ENABLE_DEBUG_INFO = YES;
234 | 				ONLY_ACTIVE_ARCH = YES;
235 | 				SDKROOT = iphoneos;
236 | 			};
237 | 			name = Debug;
238 | 		};
239 | 		6BEE0A2419870F5700D73B41 /* Release */ = {
240 | 			isa = XCBuildConfiguration;
241 | 			buildSettings = {
242 | 				ALWAYS_SEARCH_USER_PATHS = NO;
243 | 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++0x";
244 | 				CLANG_CXX_LIBRARY = "libc++";
245 | 				CLANG_ENABLE_MODULES = YES;
246 | 				CLANG_ENABLE_OBJC_ARC = YES;
247 | 				CLANG_WARN_BOOL_CONVERSION = YES;
248 | 				CLANG_WARN_CONSTANT_CONVERSION = YES;
249 | 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
250 | 				CLANG_WARN_EMPTY_BODY = YES;
251 | 				CLANG_WARN_ENUM_CONVERSION = YES;
252 | 				CLANG_WARN_INT_CONVERSION = YES;
253 | 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
254 | 				CLANG_WARN_UNREACHABLE_CODE = YES;
255 | 				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
256 | 				COPY_PHASE_STRIP = YES;
257 | 				ENABLE_NS_ASSERTIONS = NO;
258 | 				ENABLE_STRICT_OBJC_MSGSEND = YES;
259 | 				GCC_C_LANGUAGE_STANDARD = gnu99;
260 | 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
261 | 				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
262 | 				GCC_WARN_UNDECLARED_SELECTOR = YES;
263 | 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
264 | 				GCC_WARN_UNUSED_FUNCTION = YES;
265 | 				GCC_WARN_UNUSED_VARIABLE = YES;
266 | 				IPHONEOS_DEPLOYMENT_TARGET = 7.0;
267 | 				MTL_ENABLE_DEBUG_INFO = NO;
268 | 				SDKROOT = iphoneos;
269 | 				VALIDATE_PRODUCT = YES;
270 | 			};
271 | 			name = Release;
272 | 		};
273 | 		6BEE0A2619870F5700D73B41 /* Debug */ = {
274 | 			isa = XCBuildConfiguration;
275 | 			baseConfigurationReference = D6D49356F45D34F97B1E885A /* Pods.debug.xcconfig */;
276 | 			buildSettings = {
277 | 				PRODUCT_NAME = "$(TARGET_NAME)";
278 | 				SKIP_INSTALL = YES;
279 | 			};
280 | 			name = Debug;
281 | 		};
282 | 		6BEE0A2719870F5700D73B41 /* Release */ = {
283 | 			isa = XCBuildConfiguration;
284 | 			baseConfigurationReference = 2203431D931E412C4EAE5910 /* Pods.release.xcconfig */;
285 | 			buildSettings = {
286 | 				PRODUCT_NAME = "$(TARGET_NAME)";
287 | 				SKIP_INSTALL = YES;
288 | 			};
289 | 			name = Release;
290 | 		};
291 | /* End XCBuildConfiguration section */
292 | 
293 | /* Begin XCConfigurationList section */
294 | 		6BEE0A0C19870F5700D73B41 /* Build configuration list for PBXProject "BKSlidingViewController" */ = {
295 | 			isa = XCConfigurationList;
296 | 			buildConfigurations = (
297 | 				6BEE0A2319870F5700D73B41 /* Debug */,
298 | 				6BEE0A2419870F5700D73B41 /* Release */,
299 | 			);
300 | 			defaultConfigurationIsVisible = 0;
301 | 			defaultConfigurationName = Release;
302 | 		};
303 | 		6BEE0A2519870F5700D73B41 /* Build configuration list for PBXNativeTarget "BKSlidingViewController" */ = {
304 | 			isa = XCConfigurationList;
305 | 			buildConfigurations = (
306 | 				6BEE0A2619870F5700D73B41 /* Debug */,
307 | 				6BEE0A2719870F5700D73B41 /* Release */,
308 | 			);
309 | 			defaultConfigurationIsVisible = 0;
310 | 			defaultConfigurationName = Release;
311 | 		};
312 | /* End XCConfigurationList section */
313 | 	};
314 | 	rootObject = 6BEE0A0919870F5700D73B41 /* Project object */;
315 | }
316 | 


--------------------------------------------------------------------------------
/BKSlidingViewController/BKSlidingViewController.m:
--------------------------------------------------------------------------------
  1 | // Copyright 2014-present 650 Industries.
  2 | // Copyright 2015-present Andy Toulouse.
  3 | 
  4 | #import "BKSlidingViewController.h"
  5 | #import "BKSlidingViewController_Extras.h"
  6 | 
  7 | #import <BKDeltaCalculator/BKDelta.h>
  8 | #import <BKDeltaCalculator/BKDeltaCalculator.h>
  9 | 
 10 | #import "UIViewController+BKTag.h"
 11 | 
 12 | typedef NS_ENUM(NSUInteger, BKSlidingViewControllerVisibility) {
 13 |     BKSlidingViewControllerVisibilityUnchanged,
 14 |     BKSlidingViewControllerVisibilityShouldShow,
 15 |     BKSlidingViewControllerVisibilityShouldHide,
 16 | };
 17 | 
 18 | @interface BKSlidingViewController () <UIScrollViewDelegate> {
 19 |     BOOL _needsSelectedIndexUpdate;
 20 | }
 21 | 
 22 | - (void)setNeedsSelectedIndexUpdate;
 23 | - (BOOL)needsSelectedIndexUpdate;
 24 | - (void)updateSelectedIndexIfNeeded;
 25 | 
 26 | @end
 27 | 
 28 | @implementation BKSlidingViewController {
 29 |     UIScrollView *_scrollView;
 30 | 
 31 |     NSMutableArray *_viewControllers;
 32 |     NSMutableArray *_viewControllerParentViews;
 33 |     NSMapTable *_viewControllersVisible;
 34 |     NSMapTable *_viewControllersShouldChangeVisibility;
 35 | 
 36 |     CGFloat _interPageSpacing;
 37 | }
 38 | 
 39 | 
 40 | @synthesize viewControllers = _viewControllers;
 41 | 
 42 | - (void)_initializeInstance
 43 | {
 44 |     _interPageSpacing = 1;
 45 |     _viewControllers = [NSMutableArray array];
 46 |     _viewControllerParentViews = [NSMutableArray array];
 47 |     _viewControllersVisible = [NSMapTable weakToStrongObjectsMapTable];
 48 |     _viewControllersShouldChangeVisibility = [NSMapTable weakToStrongObjectsMapTable];
 49 | }
 50 | 
 51 | - (instancetype)initWithCoder:(NSCoder *)aDecoder
 52 | {
 53 |     if (self = [super initWithCoder:aDecoder]) {
 54 |         [self _initializeInstance];
 55 |     }
 56 |     return self;
 57 | }
 58 | 
 59 | - (instancetype)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
 60 | {
 61 | 
 62 |     if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
 63 |         [self _initializeInstance];
 64 |     }
 65 |     return self;
 66 | }
 67 | 
 68 | - (void)viewDidLoad
 69 | {
 70 |     [super viewDidLoad];
 71 |     _scrollView = [[UIScrollView alloc] init];
 72 |     _scrollView.bounces = NO;
 73 |     _scrollView.delaysContentTouches = NO;
 74 |     _scrollView.delegate = self;
 75 |     _scrollView.pagingEnabled = YES;
 76 |     _scrollView.showsHorizontalScrollIndicator = NO;
 77 |     _scrollView.scrollsToTop = NO;
 78 |     [self.view addSubview:_scrollView];
 79 | }
 80 | 
 81 | - (void)viewWillLayoutSubviews
 82 | {
 83 |     CGRect scrollViewRect = self.view.bounds;
 84 |     scrollViewRect.size.width += _interPageSpacing;
 85 |     _scrollView.frame = scrollViewRect;
 86 | 
 87 |     [_viewControllers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
 88 |         UIView *parentView = _viewControllerParentViews[idx];
 89 | 
 90 |         CGRect baseRect = CGRectMake(0, 0, CGRectGetWidth(self.view.bounds), CGRectGetHeight(self.view.bounds));
 91 |         CGRect offsetRect = CGRectOffset(baseRect, idx * CGRectGetWidth(_scrollView.bounds), 0);
 92 |         parentView.frame = offsetRect;
 93 |         ((UIViewController *)obj).view.frame = parentView.bounds;
 94 |     }];
 95 | 
 96 | }
 97 | 
 98 | - (BOOL)shouldAutomaticallyForwardAppearanceMethods
 99 | {
100 |     return NO;
101 | }
102 | 
103 | #pragma mark - View controller selection
104 | 
105 | - (void)setViewControllers:(NSArray *)viewControllers
106 | {
107 |     // Skip no-ops
108 |     if (_viewControllers == viewControllers || [_viewControllers isEqualToArray:viewControllers]) {
109 |         return;
110 |     }
111 | 
112 |     UIViewController *maximallyVisibleVC = [self _maximallyVisibleViewController];
113 | 
114 |     // [[[ Calculate viewcontroller differences and sync up the parent views.
115 |     BKDelta *differences = [[BKDeltaCalculator defaultCalculator] deltaFromOldArray:_viewControllers toNewArray:viewControllers];
116 |     NSIndexSet *removedIndices = differences.removedIndices;
117 |     NSIndexSet *addedIndices = differences.addedIndices;
118 | 
119 |     NSArray *removedViewControllers = [_viewControllers objectsAtIndexes:removedIndices];
120 |     NSArray *addedViewControllers = [viewControllers objectsAtIndexes:addedIndices];
121 | 
122 |     NSArray *removedParentViews = [_viewControllerParentViews objectsAtIndexes:removedIndices];
123 |     [_viewControllerParentViews removeObjectsAtIndexes:removedIndices];
124 |     [_viewControllers removeObjectsAtIndexes:removedIndices];
125 | 
126 |     [addedIndices enumerateIndexesUsingBlock:^(NSUInteger idx, BOOL *stop) {
127 |         UIViewController *addedVC = viewControllers[idx];
128 |         UIView *parentView = [[UIView alloc] init];
129 |         [parentView addSubview:addedVC.view];
130 | 
131 |         [_viewControllers insertObject:addedVC atIndex:idx];
132 |         [_viewControllerParentViews insertObject:parentView atIndex:idx];
133 |     }];
134 |     NSArray *addedParentViews = [_viewControllerParentViews objectsAtIndexes:addedIndices];
135 | 
136 |     for (UIViewController *addedVC in addedViewControllers) {
137 |         [self _setViewController:addedVC visible:NO];
138 |     }
139 |     for (UIViewController *removedVC in removedViewControllers) {
140 |         [self _setViewController:removedVC visible:NO];
141 |     }
142 |     // ]]]
143 | 
144 |     // Reconciliation logic: view controller selection
145 |     UIViewController *targetViewController;
146 |     if ([_viewControllers containsObject:_selectedViewController]) {
147 |         targetViewController = _selectedViewController;
148 |     } else if (_selectedIndex < _viewControllers.count) {
149 |         targetViewController = _viewControllers[_selectedIndex];
150 |     } else {
151 |         targetViewController = [_viewControllers lastObject];
152 |     }
153 | 
154 |     [UIView animateWithDuration:0 animations:^{ // Inherit animation context if any
155 |         [self.view layoutIfNeeded];
156 | 
157 |         for (UIViewController *viewController in removedViewControllers) {
158 |             [viewController willMoveToParentViewController:nil];
159 |         }
160 |         [addedViewControllers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
161 |             [self addChildViewController:(UIViewController *)obj];
162 |             UIView *parentView = addedParentViews[idx];
163 |             [_scrollView addSubview:parentView];
164 |             [self.view setNeedsLayout];
165 |         }];
166 | 
167 |         _scrollView.contentSize = CGSizeMake(_viewControllers.count * CGRectGetWidth(_scrollView.bounds), CGRectGetHeight(_scrollView.bounds));
168 |         [self.view layoutIfNeeded];
169 | 
170 |         // Force reselection of the view controller
171 |         [self _setSelectedViewController:targetViewController];
172 |         [self setNeedsSelectedIndexUpdate];
173 |         [self updateSelectedIndexIfNeeded];
174 |         [self _scrollViewportFromViewController:maximallyVisibleVC toViewController:targetViewController];
175 |     } completion:^(BOOL finished) {
176 |         [removedViewControllers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
177 |             UIView *parentView = removedParentViews[idx];
178 |             [parentView removeFromSuperview];
179 |             [(UIViewController *)obj removeFromParentViewController];
180 |         }];
181 |         for (UIViewController *viewController in addedViewControllers) {
182 |             [viewController didMoveToParentViewController:self];
183 |         }
184 |     }];
185 | }
186 | 
187 | - (void)setSelectedViewController:(UIViewController *)selectedViewController
188 | {
189 |     if (_selectedViewController != selectedViewController) {
190 |         UIViewController *previousSelectedVC = _selectedViewController;
191 |         [self _setSelectedViewController:selectedViewController];
192 |         [self _scrollViewportFromViewController:previousSelectedVC toViewController:_selectedViewController];
193 |     }
194 | }
195 | 
196 | // Doesn't set the viewport
197 | - (void)_setSelectedViewController:(UIViewController *)selectedViewController
198 | {
199 |     if (_selectedViewController != selectedViewController) {
200 |         _selectedViewController = selectedViewController;
201 |         [self setNeedsSelectedIndexUpdate];
202 |     }
203 | }
204 | 
205 | - (void)setSelectedIndex:(NSInteger)selectedIndex
206 | {
207 |     if (_selectedIndex != selectedIndex) {
208 |         NSAssert(selectedIndex < _viewControllers.count, @"Cannot select an index which is out of range");
209 |         UIViewController *previousSelectedVC = _selectedViewController;
210 |         [self _setSelectedViewController:_viewControllers[selectedIndex]];
211 |         [self _scrollViewportFromViewController:previousSelectedVC toViewController:_selectedViewController];
212 |     }
213 | }
214 | 
215 | #pragma mark - Selection update neediness
216 | 
217 | - (void)setNeedsSelectedIndexUpdate
218 | {
219 |     _needsSelectedIndexUpdate = YES;
220 | }
221 | 
222 | - (BOOL)needsSelectedIndexUpdate
223 | {
224 |     return _needsSelectedIndexUpdate;
225 | }
226 | 
227 | - (void)updateSelectedIndexIfNeeded
228 | {
229 |     if (_needsSelectedIndexUpdate) {
230 |         NSUInteger newSelectedIndex = [_viewControllers indexOfObject:_selectedViewController];
231 |         NSAssert(newSelectedIndex != NSNotFound, @"Cannot select a view controller which is not present");
232 | 
233 |         if (_selectedIndex != newSelectedIndex) {
234 |             [self willChangeValueForKey:@"selectedIndex"];
235 |             _selectedIndex = newSelectedIndex;
236 |             [self didChangeValueForKey:@"selectedIndex"];
237 |         }
238 |         [self setNeedsStatusBarAppearanceUpdate];
239 | 
240 |         _needsSelectedIndexUpdate = NO;
241 |     }
242 | }
243 | 
244 | #pragma mark - Tagging
245 | 
246 | - (UIViewController *)viewControllerWithTag:(NSInteger)tag
247 | {
248 |     for (UIViewController *viewController in self.viewControllers) {
249 |         if (viewController.bk_tag == tag) {
250 |             return viewController;
251 |         }
252 |     }
253 |     return nil;
254 | }
255 | 
256 | - (NSInteger)indexWithTag:(NSInteger)tag
257 | {
258 |     for (NSUInteger i = 0; i < self.viewControllers.count; i++) {
259 |         UIViewController *viewController = self.viewControllers[i];
260 |         if (viewController.bk_tag == tag) {
261 |             return i;
262 |         }
263 |     }
264 |     return NSNotFound;
265 | }
266 | 
267 | #pragma mark - Child view controller status bar methods
268 | 
269 | - (UIViewController *)childViewControllerForStatusBarStyle
270 | {
271 |     return _selectedViewController;
272 | }
273 | 
274 | - (UIViewController *)childViewControllerForStatusBarHidden
275 | {
276 |     return _selectedViewController;
277 | }
278 | 
279 | #pragma mark - <UIScrollViewDelegate>
280 | 
281 | - (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
282 | {
283 |     if ([_delegate respondsToSelector:@selector(slidingViewControllerWillBeginDragging:)]) {
284 |         [_delegate slidingViewControllerWillBeginDragging:self];
285 |     }
286 | }
287 | 
288 | - (void)scrollViewDidScroll:(UIScrollView *)scrollView
289 | {
290 |     CGFloat scrollViewWidth = CGRectGetWidth(scrollView.bounds);
291 |     CGRect visibleRect = [self _viewport];
292 | 
293 |     CGFloat middleOffset = CGRectGetMidX(visibleRect);
294 |     CGFloat approximateMiddleIndex = middleOffset / scrollViewWidth;
295 |     NSInteger middleIndex = (NSInteger)floor(approximateMiddleIndex);
296 | 
297 |     NSUInteger minIndex = middleIndex > 0 ? middleIndex - 1 : 0;
298 |     NSUInteger maxIndex = middleIndex < (_viewControllers.count - 1) ? middleIndex + 1 : _viewControllers.count - 1;
299 |     NSRange validIndexRange = NSMakeRange(minIndex, maxIndex - minIndex + 1);
300 |     NSIndexSet *validIndicesToCheck = [NSIndexSet indexSetWithIndexesInRange:validIndexRange];
301 |     [_viewControllers enumerateObjectsAtIndexes:validIndicesToCheck
302 |                                         options:0
303 |                                      usingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
304 |                                          UIViewController *vc = obj;
305 |                                          UIView *parentView = _viewControllerParentViews[idx];
306 | 
307 |                                          BOOL intersects = CGRectIntersectsRect(visibleRect, ((CALayer *)parentView.layer.presentationLayer).frame);
308 |                                          if (intersects) {
309 |                                              [self _setViewController:vc shouldChangeVisibility:BKSlidingViewControllerVisibilityShouldShow];
310 |                                              [self _updateAppearanceForViewControllerIfNeeded:vc animated:YES];
311 |                                          }
312 |                                      }];
313 | 
314 |     if ([_delegate respondsToSelector:@selector(slidingViewControllerDidScroll:)]) {
315 |         [_delegate slidingViewControllerDidScroll:self];
316 |     }
317 | }
318 | 
319 | - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
320 | {
321 |     UIViewController *maximallyVisibleVC = [self _maximallyVisibleViewController];
322 |     for (UIViewController *viewController in _viewControllers) {
323 |         if (maximallyVisibleVC == viewController) {
324 |             continue;
325 |         }
326 |         [self _setViewController:viewController shouldChangeVisibility:BKSlidingViewControllerVisibilityShouldHide];
327 |         [self _updateAppearanceForViewControllerIfNeeded:viewController animated:NO];
328 |     }
329 | 
330 |     [self _setSelectedViewController:maximallyVisibleVC];
331 |     [self updateSelectedIndexIfNeeded];
332 | 
333 |     if ([_delegate respondsToSelector:@selector(slidingViewControllerDidEndDecelerating:)]) {
334 |         [_delegate slidingViewControllerDidEndDecelerating:self];
335 |     }
336 | }
337 | 
338 | #pragma mark - Extra method
339 | 
340 | - (CGFloat)percentScrolled
341 | {
342 |     CGFloat screenWidth = CGRectGetWidth(_scrollView.bounds);
343 |     CGFloat totalWidth = _scrollView.contentSize.width + _scrollView.contentInset.left + _scrollView.contentInset.right;
344 |     CGFloat workingWidth = totalWidth - screenWidth;
345 | 
346 |     CGFloat insetAdjustedXOffset = _scrollView.contentInset.left + _scrollView.contentOffset.x;
347 |     CGFloat percent;
348 |     if (workingWidth == 0) {
349 |         percent = 0.5;
350 |     } else {
351 |         percent = insetAdjustedXOffset / workingWidth;
352 |     }
353 |     return percent;
354 | }
355 | 
356 | #pragma mark - Rotation (NOTE: currently disabled)
357 | 
358 | // Disabled for now - rotation isn't production-ready.
359 | - (BOOL)shouldAutorotate
360 | {
361 |     return NO;
362 | }
363 | 
364 | #if defined(__IPHONE_8_0)
365 | // iOS 8
366 | - (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator
367 | {
368 |     [coordinator animateAlongsideTransition:^(id<UIViewControllerTransitionCoordinatorContext> context) {
369 |         CGFloat screenWidth = CGRectGetWidth(_scrollView.bounds);
370 |         _scrollView.contentOffset = CGPointMake(self.selectedIndex * screenWidth, 0);
371 |         _scrollView.contentSize = CGSizeMake(_viewControllers.count * CGRectGetWidth(_scrollView.bounds), CGRectGetHeight(_scrollView.bounds));
372 |     } completion:nil];
373 | 
374 |     [super viewWillTransitionToSize:size withTransitionCoordinator:coordinator];
375 | }
376 | #endif
377 | 
378 | // iOS <= 7
379 | - (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
380 | {
381 |     CGFloat screenWidth = CGRectGetWidth(_scrollView.bounds);
382 |     _scrollView.contentOffset = CGPointMake(self.selectedIndex * screenWidth, 0);
383 |     _scrollView.contentSize = CGSizeMake(_viewControllers.count * CGRectGetWidth(_scrollView.bounds), CGRectGetHeight(_scrollView.bounds));
384 |     [self.view layoutIfNeeded];
385 | 
386 |     [super willAnimateRotationToInterfaceOrientation:toInterfaceOrientation duration:duration];
387 | }
388 | 
389 | #pragma mark - Helpers
390 | 
391 | - (UIViewController *)_maximallyVisibleViewController
392 | {
393 |     // Find visible view controllers
394 |     CGRect visibleRect = [self _viewport];
395 |     NSArray *visibleViewControllers = [self _viewControllersVisibleInRect:visibleRect];
396 | 
397 |     __block CGFloat maximumArea = -1;
398 |     __block UIViewController *maximallyVisibleVC = nil;
399 |     [visibleViewControllers enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
400 |         UIViewController *visibleVC = obj;
401 |         UIView *parentView = _viewControllerParentViews[idx];
402 |         CGRect intersection = CGRectIntersection(visibleRect, parentView.frame);
403 |         CGFloat area = intersection.size.width * intersection.size.height;
404 |         if (area > maximumArea) {
405 |             maximumArea = area;
406 |             maximallyVisibleVC = visibleVC;
407 |         }
408 |     }];
409 |     return maximallyVisibleVC;
410 | }
411 | 
412 | - (CGRect)_viewport
413 | {
414 |     CALayer *visibleLayer = _scrollView.layer.presentationLayer;
415 |     CGRect visibleRect = visibleLayer.bounds;
416 |     return visibleRect;
417 | }
418 | 
419 | - (NSArray *)_viewControllersVisibleInRect:(CGRect)rect
420 | {
421 |     NSMutableArray *visibleViewControllers = [NSMutableArray array];
422 |     [_viewControllerParentViews enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
423 |         UIViewController *visibleVC = _viewControllers[idx];
424 |         UIView *parentView = obj;
425 |         if (CGRectIntersectsRect(rect, parentView.frame)) {
426 |             [visibleViewControllers addObject:visibleVC];
427 |         }
428 |     }];
429 |     return visibleViewControllers;
430 | }
431 | 
432 | - (void)_scrollViewportFromViewController:(UIViewController *)fromViewController
433 |                          toViewController:(UIViewController *)toViewController
434 | {
435 |     CGRect targetRect = toViewController.view.superview.frame;
436 |     CGFloat zoomScale = CGRectGetWidth(toViewController.view.superview.frame) / fmax(CGRectGetWidth(self.view.bounds), 1); // fmax to avoid div-by-0
437 |     CGRect transformedRect = CGRectApplyAffineTransform(targetRect, CGAffineTransformMakeScale(zoomScale, zoomScale));
438 |     _scrollView.contentOffset = transformedRect.origin;
439 |     _scrollView.zoomScale = zoomScale;
440 | 
441 |     // Magic to figure out if our scrollview is animating its contentOffset change. Must happen _after_ the change,
442 |     // because it works by detecting the added animation. NOTE: 0.001 seems to be the usual animation duration for
443 |     // 'instant' animations. 0.25 is CATransaction's default animationDuration (for implicit animations).
444 |     CAAnimation *animation = [_scrollView.layer animationForKey:@"bounds"];
445 |     // if someone disabled actions and there are _no_ animations, nil < 0.001
446 |     BOOL isAnimating = animation.duration > 0.001;
447 | 
448 |     [self _setViewController:fromViewController shouldChangeVisibility:BKSlidingViewControllerVisibilityShouldHide];
449 |     [self _setViewController:toViewController shouldChangeVisibility:BKSlidingViewControllerVisibilityShouldShow];
450 | 
451 |     [self updateSelectedIndexIfNeeded];
452 | 
453 |     [self _updateAppearanceForViewControllerIfNeeded:fromViewController animated:isAnimating];
454 |     [self _updateAppearanceForViewControllerIfNeeded:toViewController animated:isAnimating];
455 | }
456 | 
457 | - (void)_updateAppearanceForViewControllerIfNeeded:(UIViewController *)viewController animated:(BOOL)animated
458 | {
459 |     BOOL needed = [self _appearanceTransitionNeededForViewController:viewController];
460 |     if (!needed) {
461 |         [self _setViewController:viewController shouldChangeVisibility:BKSlidingViewControllerVisibilityUnchanged];
462 |         return;
463 |     }
464 | 
465 |     BOOL isAppearing = [self _shouldChangeVisibilityForViewController:viewController] == BKSlidingViewControllerVisibilityShouldShow;
466 |     [viewController beginAppearanceTransition:isAppearing animated:animated];
467 | 
468 |     void (^animationBlock)(void) = ^{
469 |         if (isAppearing) {
470 |             viewController.view.hidden = NO;
471 |         }
472 |         [self _setViewController:viewController visible:isAppearing];
473 |     };
474 |     void (^completionBlock)(void) = ^{
475 |         [viewController endAppearanceTransition];
476 |         [self _setViewController:viewController shouldChangeVisibility:BKSlidingViewControllerVisibilityUnchanged];
477 |     };
478 | 
479 |     if (!animated) {
480 |         animationBlock();
481 |         completionBlock();
482 |     } else {
483 |         [UIView animateWithDuration:0
484 |                          animations:animationBlock
485 |                          completion:^(BOOL finished) {
486 |                              completionBlock();
487 |                          }];
488 |     }
489 | }
490 | 
491 | - (BOOL)_appearanceTransitionNeededForViewController:(UIViewController *)viewController
492 | {
493 |     BOOL isVisible = [self _visibilityForViewController:viewController];
494 |     BKSlidingViewControllerVisibility desiredVisibility = [self _shouldChangeVisibilityForViewController:viewController];
495 |     switch (desiredVisibility) {
496 |         case BKSlidingViewControllerVisibilityUnchanged:
497 |             return NO;
498 |         case BKSlidingViewControllerVisibilityShouldShow:
499 |             return !isVisible;
500 |         case BKSlidingViewControllerVisibilityShouldHide:
501 |             return isVisible;
502 |     }
503 | }
504 | 
505 | - (BOOL)_visibilityForViewController:(UIViewController *)viewController
506 | {
507 |     return [(NSNumber *)[_viewControllersVisible objectForKey:viewController] boolValue];
508 | }
509 | 
510 | - (void)_setViewController:(UIViewController *)viewController visible:(BOOL)visible
511 | {
512 |     [_viewControllersVisible setObject:@(visible) forKey:viewController];
513 | }
514 | 
515 | - (BKSlidingViewControllerVisibility)_shouldChangeVisibilityForViewController:(UIViewController *)viewController
516 | {
517 |     return [(NSNumber *)[_viewControllersShouldChangeVisibility objectForKey:viewController] unsignedIntegerValue];
518 | }
519 | 
520 | - (void)_setViewController:(UIViewController *)viewController shouldChangeVisibility:(BKSlidingViewControllerVisibility)change
521 | {
522 |     [_viewControllersShouldChangeVisibility setObject:@(change) forKey:viewController];
523 | }
524 | 
525 | @end


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