Fixed the ButtonBarView animation when scrolling back to the first and the last element

Example.xcodeproj/project.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>

Sources/ButtonBarView.swift

@@ -76,10 +76,28 @@ open class ButtonBarView: UICollectionView {
     }
 
     open func move(fromIndex: Int, toIndex: Int, progressPercentage: CGFloat, pagerScroll: PagerScroll) {
+
         selectedIndex = progressPercentage > 0.5 ? toIndex : fromIndex
 
-        let fromFrame = layoutAttributesForItem(at: IndexPath(item: fromIndex, section: 0))!.frame
         let numberOfItems = dataSource!.collectionView(self, numberOfItemsInSection: 0)
+        var progressPercentage = progressPercentage
+
+
+        var fromFrame: CGRect
+
+        if fromIndex < 0 || fromIndex > numberOfItems - 1 {
+            if fromIndex < 0 {
+                let cellAtts = layoutAttributesForItem(at: IndexPath(item: 0, section: 0))
+                fromFrame = cellAtts!.frame.offsetBy(dx: -cellAtts!.frame.size.width, dy: 0)
+                progressPercentage = 1 - progressPercentage * -1
+            } else {
+                let cellAtts = layoutAttributesForItem(at: IndexPath(item: (numberOfItems - 1), section: 0))
+                fromFrame = cellAtts!.frame.offsetBy(dx: cellAtts!.frame.size.width, dy: 0)
+            }
+        } else {
+            fromFrame = layoutAttributesForItem(at: IndexPath(item: fromIndex, section: 0))!.frame
+        }
+
 
         var toFrame: CGRect
 
@@ -95,11 +113,12 @@ open class ButtonBarView: UICollectionView {
             toFrame = layoutAttributesForItem(at: IndexPath(item: toIndex, section: 0))!.frame
         }
 
+
         var targetFrame = fromFrame
         targetFrame.size.height = selectedBar.frame.size.height
         targetFrame.size.width += (toFrame.size.width - fromFrame.size.width) * progressPercentage
         targetFrame.origin.x += (toFrame.origin.x - fromFrame.origin.x) * progressPercentage
-
+        
         selectedBar.frame = CGRect(x: targetFrame.origin.x, y: selectedBar.frame.origin.y, width: targetFrame.size.width, height: selectedBar.frame.size.height)
 
         var targetContentOffset: CGFloat = 0.0

Sources/ButtonCell.xib

@@ -1,17 +1,17 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="12120" systemVersion="16E195" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="14113" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" colorMatched="YES">
     <device id="retina4_7" orientation="portrait">
         <adaptation id="fullscreen"/>
     </device>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="12088"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14088"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <objects>
         <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner"/>
         <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
-        <collectionViewCell opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" id="zg4-fX-zUF" customClass="ButtonBarViewCell" customModule="XLPagerTabStrip" customModuleProvider="target">
+        <collectionViewCell opaque="NO" multipleTouchEnabled="YES" contentMode="center" id="zg4-fX-zUF" customClass="ButtonBarViewCell" customModule="XLPagerTabStrip" customModuleProvider="target">
             <rect key="frame" x="0.0" y="0.0" width="80" height="40"/>
             <autoresizingMask key="autoresizingMask" flexibleMaxX="YES" flexibleMaxY="YES"/>
             <view key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center">

Sources/PagerTabStripViewController.swift

@@ -299,7 +299,7 @@ open class PagerTabStripViewController: UIViewController, UIScrollViewDelegate {
         updateContent()
     }
 
-    // MARK: - UIScrollViewDelegate
+    // MARK: - UIScrollDelegate
 
     open func scrollViewDidScroll(_ scrollView: UIScrollView) {
         if containerView == scrollView {
@@ -350,14 +350,21 @@ open class PagerTabStripViewController: UIViewController, UIScrollViewDelegate {
                 fromIndex = count - 1
                 toIndex = count
             } else {
-                if self.scrollPercentage >= 0.5 {
+                if self.scrollPercentage <= 0 {
+                    toIndex = currentIndex
+                    fromIndex = currentIndex - 1
+                }
+                else if self.scrollPercentage >= 0.5 {
                     fromIndex = max(toIndex - 1, 0)
                 } else {
                     toIndex = fromIndex + 1
                 }
             }
         } else if direction == .right {
-            if virtualPage < 0 {
+            if virtualPage >= count - 1 && self.scrollPercentage > 0.5 {
+                fromIndex = count
+                toIndex = count - 1
+            } else if virtualPage < 0 {
                 fromIndex = 0
                 toIndex = -1
             } else {

XLPagerTabStrip.xcodeproj/xcshareddata/xcschemes/XLPagerTabStrip.xcscheme

@@ -1,6 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
+<<<<<<< HEAD
+   LastUpgradeVersion = "1000"
+=======
    LastUpgradeVersion = "1020"
+>>>>>>> xmartlabs/master
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"