Allow customization of NUX button view shadows constraints

WordPressAuthenticator.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name          = "WordPressAuthenticator"
-  s.version       = "1.36.0-beta.3"
+  s.version       = "1.36.0-beta.4"
 
   s.summary       = "WordPressAuthenticator implements an easy and elegant way to authenticate your WordPress Apps."
   s.description   = <<-DESC

WordPressAuthenticator/NUX/NUXButtonView.storyboard

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="16097.3" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="17701" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES">
     <device id="retina4_7" orientation="portrait" appearance="light"/>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="16087"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17703"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
@@ -47,7 +47,7 @@
                                         </constraints>
                                         <fontDescription key="fontDescription" style="UICTFontTextStyleHeadline"/>
                                         <state key="normal" title="Primary Button">
-                                            <color key="titleColor" cocoaTouchSystemColor="darkTextColor"/>
+                                            <color key="titleColor" systemColor="darkTextColor"/>
                                         </state>
                                         <state key="highlighted">
                                             <color key="titleColor" white="1" alpha="1" colorSpace="calibratedWhite"/>
@@ -64,7 +64,7 @@
                                         </constraints>
                                         <fontDescription key="fontDescription" style="UICTFontTextStyleHeadline"/>
                                         <state key="normal" title="Cancel Button">
-                                            <color key="titleColor" cocoaTouchSystemColor="darkTextColor"/>
+                                            <color key="titleColor" systemColor="darkTextColor"/>
                                         </state>
                                         <state key="highlighted">
                                             <color key="titleColor" white="1" alpha="1" colorSpace="calibratedWhite"/>
@@ -76,6 +76,7 @@
                                 </subviews>
                             </stackView>
                         </subviews>
+                        <viewLayoutGuide key="safeArea" id="vC0-ge-46d"/>
                         <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
                         <constraints>
                             <constraint firstItem="RrB-Aa-ADd" firstAttribute="leading" secondItem="vC0-ge-46d" secondAttribute="leading" id="29Q-jd-hiu"/>
@@ -86,7 +87,6 @@
                             <constraint firstItem="vC0-ge-46d" firstAttribute="trailing" secondItem="xzf-f5-7zQ" secondAttribute="trailing" constant="16" id="pdk-yI-G0O"/>
                             <constraint firstItem="RrB-Aa-ADd" firstAttribute="top" secondItem="vC0-ge-46d" secondAttribute="top" constant="-10" id="qZc-jk-YRs"/>
                         </constraints>
-                        <viewLayoutGuide key="safeArea" id="vC0-ge-46d"/>
                     </view>
                     <size key="freeformSize" width="375" height="136"/>
                     <connections>
@@ -96,6 +96,8 @@
                         <outlet property="stackView" destination="xzf-f5-7zQ" id="frG-Oo-nB4"/>
                         <outlet property="tertiaryButton" destination="uAF-kU-f7P" id="B6D-lx-GhC"/>
                         <outlet property="topButton" destination="knN-O6-M86" id="3fN-Bh-Z8O"/>
+                        <outletCollection property="shadowViewEdgeConstraints" destination="29Q-jd-hiu" collectionClass="NSMutableArray" id="Um7-mZ-AvI"/>
+                        <outletCollection property="shadowViewEdgeConstraints" destination="APL-hI-Fg5" collectionClass="NSMutableArray" id="K7W-dN-UTb"/>
                     </connections>
                 </viewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="7sJ-Ej-Lr7" userLabel="First Responder" sceneMemberID="firstResponder"/>
@@ -105,5 +107,8 @@
     </scenes>
     <resources>
         <image name="darkgrey-shadow" width="10" height="10"/>
+        <systemColor name="darkTextColor">
+            <color white="0.0" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
+        </systemColor>
     </resources>
 </document>

WordPressAuthenticator/NUX/NUXButtonViewController.swift

@@ -34,13 +34,23 @@ open class NUXButtonViewController: UIViewController {
 
     // MARK: - Properties
 
-    @IBOutlet private var shadowView: UIImageView?
     @IBOutlet var stackView: UIStackView?
     @IBOutlet var bottomButton: NUXButton?
     @IBOutlet var topButton: NUXButton?
     @IBOutlet var tertiaryButton: NUXButton?
     @IBOutlet var buttonHolder: UIView?
 
+    @IBOutlet private var shadowView: UIImageView?
+    @IBOutlet private var shadowViewEdgeConstraints: [NSLayoutConstraint]!
+
+    /// Used to constrain the shadow view outside of the
+    /// bounds of this view controller.
+    weak var shadowLayoutGuide: UILayoutGuide? {
+        didSet {
+            updateShadowViewEdgeConstraints()
+        }
+    }
+
     open weak var delegate: NUXButtonViewControllerDelegate?
     open var backgroundColor: UIColor?
 
@@ -91,6 +101,23 @@ open class NUXButtonViewController: UIViewController {
         }
     }
 
+    private func updateShadowViewEdgeConstraints() {
+        guard let layoutGuide = shadowLayoutGuide,
+              let shadowView = shadowView else {
+            return
+        }
+
+        NSLayoutConstraint.deactivate(shadowViewEdgeConstraints)
+        shadowView.translatesAutoresizingMaskIntoConstraints = false
+
+        shadowViewEdgeConstraints = [
+            layoutGuide.leadingAnchor.constraint(equalTo: shadowView.leadingAnchor),
+            layoutGuide.trailingAnchor.constraint(equalTo: shadowView.trailingAnchor),
+        ]
+
+        NSLayoutConstraint.activate(shadowViewEdgeConstraints)
+    }
+
     // MARK: public API
 
     /// Public method to set the button titles.

WordPressAuthenticator/Signin/LoginPrologueViewController.swift

@@ -163,6 +163,8 @@ class LoginPrologueViewController: LoginViewController {
         }
 
         buildUnifiedPrologueButtons(buttonViewController)
+
+        buttonViewController.shadowLayoutGuide = view.safeAreaLayoutGuide
     }
 
     /// Displays the old UI prologue buttons.