Add the possibility to wrap the stack view within the superview's layout margins

Example/AloeStackViewExample.xcodeproj/project.pbxproj

@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		3EE7174D22045E54006E6F75 /* PreserveLayoutMarginsViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 3EE7174C22045E54006E6F75 /* PreserveLayoutMarginsViewController.swift */; };
 		A7497A9121746D9700BB692A /* AloeStackView.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = A7497A9021746D9700BB692A /* AloeStackView.framework */; };
 		A7497A932174725700BB692A /* SwitchRowView.swift in Sources */ = {isa = PBXBuildFile; fileRef = A7497A922174725700BB692A /* SwitchRowView.swift */; };
 		A7497A9721747DD600BB692A /* PhotoViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = A7497A9621747DD600BB692A /* PhotoViewController.swift */; };
@@ -18,6 +19,7 @@
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
+		3EE7174C22045E54006E6F75 /* PreserveLayoutMarginsViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PreserveLayoutMarginsViewController.swift; sourceTree = "<group>"; };
 		A7420FAB21715DF500F2A343 /* Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		A7497A9021746D9700BB692A /* AloeStackView.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = AloeStackView.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		A7497A922174725700BB692A /* SwitchRowView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SwitchRowView.swift; sourceTree = "<group>"; };
@@ -47,6 +49,7 @@
 			children = (
 				A74F70BA217155FC0054AA18 /* MainViewController.swift */,
 				A7497A9621747DD600BB692A /* PhotoViewController.swift */,
+				3EE7174C22045E54006E6F75 /* PreserveLayoutMarginsViewController.swift */,
 			);
 			path = ViewControllers;
 			sourceTree = "<group>";
@@ -204,6 +207,7 @@
 				A7497A9721747DD600BB692A /* PhotoViewController.swift in Sources */,
 				A74F70B9217155FC0054AA18 /* AppDelegate.swift in Sources */,
 				A7497A9921755AD100BB692A /* ExpandingRowView.swift in Sources */,
+				3EE7174D22045E54006E6F75 /* PreserveLayoutMarginsViewController.swift in Sources */,
 				A7497A932174725700BB692A /* SwitchRowView.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

Example/AloeStackViewExample/ViewControllers/MainViewController.swift

@@ -43,6 +43,7 @@ public class MainViewController: AloeStackViewController {
     setUpHiddenRows()
     setUpExpandingRowView()
     setUpPhotoRow()
+    setUpPreserveLayoutMarginsRow()
   }
 
   private func setUpDescriptionRow() {
@@ -137,4 +138,19 @@ public class MainViewController: AloeStackViewController {
     }
   }
 
+  private func setUpPreserveLayoutMarginsRow() {
+    let label = UILabel()
+    label.font = UIFont.preferredFont(forTextStyle: .body)
+    label.numberOfLines = 0
+    label.text = "Tap here to view an AloeStackView constrained within its superview's layout margins."
+    label.isUserInteractionEnabled = true
+
+    stackView.addRow(label)
+    stackView.setTapHandler(forRow: label) { [weak self] _ in
+        guard let self = self else { return }
+        let vc = PreserveLayoutMarginsViewController()
+        self.navigationController?.pushViewController(vc, animated: true)
+    }
+  }
+
 }

Example/AloeStackViewExample/ViewControllers/PreserveLayoutMarginsViewController.swift

@@ -0,0 +1,66 @@
+//  Created by Alexander Bredy on 01/02/2019.
+//  Copyright © 2019 Airbnb, Inc. All rights reserved.
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+// http://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import AloeStackView
+import UIKit
+
+public class PreserveLayoutMarginsViewController: AloeStackViewController {
+
+  // MARK: Public
+
+  public override func viewDidLoad() {
+    super.viewDidLoad()
+    setUpSelf()
+    setUpStackView()
+    setUpRows()
+  }
+
+  // MARK: Private
+
+  private func setUpSelf() {
+    title = "Preserve superview layout margins"
+  }
+
+  private func setUpStackView() {
+    // Setting this property to true will constrain the stack view content within the layout margins of the superview
+    stackView.preservesSuperviewLayoutMargins = true
+
+    // Setting separator and row insets on this screen will add additional margins to the ones set by the
+    // superview.
+    stackView.separatorInset = .zero
+    stackView.rowInset = .zero
+  }
+
+  private func setUpRows() {
+    setUpDescriptionRow()
+    setUpAnotherRow()
+  }
+
+  private func setUpDescriptionRow() {
+    let label = UILabel()
+    label.font = UIFont.preferredFont(forTextStyle: .body)
+    label.numberOfLines = 0
+    label.text = "The margins of the AloeStackView in this screen include the ones from the superview layout margins."
+    stackView.addRow(label)
+  }
+
+  private func setUpAnotherRow() {
+    let label = UILabel()
+    label.font = UIFont.preferredFont(forTextStyle: .body)
+    label.numberOfLines = 0
+    label.text = "Check out this ViewController on both iPhone and iPad to see the margins difference!"
+    stackView.addRow(label)
+  }
+}

Sources/AloeStackView/AloeStackView.swift

@@ -304,6 +304,18 @@ open class AloeStackView: UIScrollView {
     }
   }
 
+  /// Set whether the layout margins of the superview should be included.
+  ///
+  /// This comes in handy as iPhones and iPads can have different layout margins
+  /// and convenient as it automatically provide an inset to all the rows
+  /// without having to set it explicitely.
+  open override var preservesSuperviewLayoutMargins: Bool {
+    didSet {
+        stackView.preservesSuperviewLayoutMargins = preservesSuperviewLayoutMargins
+        stackView.isLayoutMarginsRelativeArrangement = preservesSuperviewLayoutMargins
+    }
+  }
+
   /// Specifies the default inset of row separators.
   ///
   /// Only left and right insets are honored. This inset will be used for any new row that is added