Merge pull request #11 from hyperoslo/feature/bottom-line-view

Add bottom line view

Author: 3lvis

Pod/PagesDemo/AppDelegate.swift

@@ -8,19 +8,19 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
     func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
 
       let viewController1 = UIViewController()
-      viewController1.view.backgroundColor = UIColor.redColor()
+      viewController1.view.backgroundColor = .blackColor()
       viewController1.title = "Controller A"
 
       let viewController2 = UIViewController()
-      viewController2.view.backgroundColor = UIColor.blueColor()
+      viewController2.view.backgroundColor = .blueColor()
       viewController2.title = "Controller B"
 
       let viewController3 = UIViewController()
-      viewController3.view.backgroundColor = UIColor.greenColor()
+      viewController3.view.backgroundColor = .redColor()
       viewController3.title = "Controller C"
 
       let viewController4 = UIViewController()
-      viewController4.view.backgroundColor = UIColor.yellowColor()
+      viewController4.view.backgroundColor = .yellowColor()
       viewController4.title = "Controller D"
 
       let pages = PagesController([viewController1,
@@ -30,6 +30,7 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
         ])
 
       pages.enableSwipe = false
+      pages.showBottomLine = true
 
       let navigationController = UINavigationController(rootViewController: pages)
 

Source/PagesController.swift

@@ -7,6 +7,12 @@ import UIKit
 
 @objc(HYPPagesController) public class PagesController: UIPageViewController, UIPageViewControllerDelegate, UIPageViewControllerDataSource {
 
+  struct Dimensions {
+    static let bottomLineHeight: CGFloat = 1.0
+    static let bottomLineSideMargin: CGFloat = 40.0
+    static let bottomLineBottomMargin: CGFloat = 36.0
+  }
+
   public var startPage = 0
   public var setNavigationTitle = true
 
@@ -16,12 +22,27 @@ import UIKit
     }
   }
 
+  public var showBottomLine = false {
+    didSet {
+      bottomLineView.hidden = !showBottomLine
+    }
+  }
+
   lazy var pages = Array<UIViewController>()
 
   public private(set) var currentIndex = 0
 
   public var pagesDelegate: PagesControllerDelegate?
 
+  public private(set) var bottomLineView: UIView = {
+    let view = UIView()
+    view.setTranslatesAutoresizingMaskIntoConstraints(false)
+    view.backgroundColor = .whiteColor()
+    view.alpha = 0.4
+    view.hidden = true
+    return view
+    }()
+
   public convenience init(_ pages: [UIViewController],
     transitionStyle: UIPageViewControllerTransitionStyle = .Scroll,
     navigationOrientation: UIPageViewControllerNavigationOrientation = .Horizontal,
@@ -38,6 +59,10 @@ import UIKit
 
     delegate = self
     dataSource = self
+
+    view.addSubview(bottomLineView)
+    addConstraints()
+    view.bringSubviewToFront(bottomLineView)
     goTo(startPage)
   }
 }
@@ -56,7 +81,7 @@ extension PagesController {
         completion: { [unowned self] finished in
           self.pagesDelegate?.pageViewController(self,
             setViewController: viewController,
-            atPage: currentIndex)
+            atPage: self.currentIndex)
         })
       if setNavigationTitle {
         title = viewController.title
@@ -151,13 +176,31 @@ extension PagesController {
         completion: { [unowned self] finished in
           self.pagesDelegate?.pageViewController(self,
             setViewController: viewController,
-            atPage: currentIndex)
+            atPage: self.currentIndex)
         })
       if setNavigationTitle {
         title = viewController.title
       }
     }
   }
+
+  private func addConstraints() {
+    view.addConstraint(NSLayoutConstraint(item: bottomLineView, attribute: .Bottom,
+      relatedBy: .Equal, toItem: view, attribute: .Bottom,
+      multiplier: 1, constant: -Dimensions.bottomLineBottomMargin))
+
+    view.addConstraint(NSLayoutConstraint(item: bottomLineView, attribute: .Left,
+      relatedBy: .Equal, toItem: view, attribute: .Left,
+      multiplier: 1, constant: Dimensions.bottomLineSideMargin))
+
+    view.addConstraint(NSLayoutConstraint(item: bottomLineView, attribute: .Right,
+      relatedBy: .Equal, toItem: view, attribute: .Right,
+      multiplier: 1, constant: -Dimensions.bottomLineSideMargin))
+
+    view.addConstraint(NSLayoutConstraint(item: bottomLineView, attribute: .Height,
+      relatedBy: .Equal, toItem: nil, attribute: .NotAnAttribute,
+      multiplier: 1, constant: Dimensions.bottomLineHeight))
+  }
 }
 
 extension Array {
@@ -179,4 +222,3 @@ func nextIndex(x: Int?) -> Int? {
 func prevIndex(x: Int?) -> Int? {
   return x.map { $0 - 1 }
 }
-