Increasing safety in loadFromNib

CHANGELOG.md

@@ -1,5 +1,22 @@
 # CHANGELOG
 
+## Unreleased
+
+### Breaking change
+
+* `static func loadFromNib(owner:)` of `NibOwnerLoadable` has been replaced by instance method `func loadNibContent()`.  
+  This is more consistent and also avoids possible crashes when used with `UIView` subclasses not implementing non-required initializers `init()`/`init(frame:)`.  
+  [@Skoti](https://github.com/Skoti)
+  [#40](https://github.com/AliSoftware/Reusable/pull/40)
+
+### Enhancements
+
+* Fixing documentation typos for `CollectionHeaderView` and `MyXIBIndexSquaceCell`.  
+  [@Skoti](https://github.com/Skoti)
+
+* Fixing table view controller scene in Example project, to display cells above `UITabBar`.  
+  [@Skoti](https://github.com/Skoti)
+
 ## 3.0.1
 
 * Fix `instantiate()` implementation on `StoryboardSceneBased` ViewControllers.  

Example/ReusableDemo/Base.lproj/Main.storyboard

@@ -1,5 +1,5 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="15G31" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="7fF-Ae-xTS">
+<?xml version="1.0" encoding="UTF-8"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="10117" systemVersion="16D32" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="7fF-Ae-xTS">
     <dependencies>
         <deployment identifier="iOS"/>
         <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="10085"/>
@@ -90,6 +90,7 @@
                             <outlet property="delegate" destination="Spa-tB-Bt1" id="iqn-sB-Tfo"/>
                         </connections>
                     </tableView>
+                    <extendedEdge key="edgesForExtendedLayout" top="YES"/>
                     <tabBarItem key="tabBarItem" title="TableView" id="C3o-Lt-Bjj"/>
                 </tableViewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="XEN-tN-mKX" userLabel="First Responder" sceneMemberID="firstResponder"/>

Example/ReusableDemo/CollectionViewCells/CollectionHeaderView.swift

@@ -16,7 +16,7 @@ import Reusable
  * It is also reusable and has a `reuseIdentifier` (as it's a CollectionViewCell
  * and it uses the CollectionView recycling mechanism) => it is `Reusable`
  *
- * That's why it's annotated with the `NibOwnerLoadable` protocol,
+ * That's why it's annotated with the `NibReusable` protocol,
  * Which in fact is just a convenience typealias that combines
  * `NibLoadable` & `Reusable` protocols.
  */

Example/ReusableDemo/CollectionViewCells/MyXIBIndexSquaceCell.swift

@@ -16,7 +16,7 @@ import Reusable
  * It is also reusable and has a `reuseIdentifier` (as it's a CollectionViewCell
  * and it uses the CollectionView recycling mechanism) => it is `Reusable`
  *
- * That's why it's annotated with the `NibOwnerLoadable` protocol,
+ * That's why it's annotated with the `NibReusable` protocol,
  * Which in fact is just a typealias that combines
  * `NibLoadable` & `Reusable` protocols.
  */

Example/ReusableDemo/CustomViews/MyCustomWidget.swift

@@ -26,9 +26,6 @@ class MyCustomWidget: UIView, NibOwnerLoadable {
 
   required init?(coder aDecoder: NSCoder) {
     super.init(coder: aDecoder)
-    MyCustomWidget.loadFromNib(owner: self)
-  }
-  override init(frame: CGRect) {
-    super.init(frame: frame)
+    self.loadNibContent()
   }
 }

Example/ReusableDemo/TableViewCells/MyHeaderTableView.swift

@@ -22,6 +22,7 @@ final class MyHeaderTableView: UIView, NibOwnerLoadable {
 
   override init(frame: CGRect) {
     super.init(frame: frame)
+    self.loadNibContent()
   }
 
   required init?(coder aDecoder: NSCoder) {

Example/ReusableDemo/TableViewController.swift

@@ -27,7 +27,12 @@ final class TableViewController: UITableViewController {
   }
 
   override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
-    let view = MyHeaderTableView.loadFromNib()
+    let frame = CGRect(x: 0, y: 0, width: tableView.bounds.size.width, height: self.tableView(tableView, heightForHeaderInSection: section))
+
+    // See the overridden `MyHeaderTableView.init(frame:)` initializer, which
+    // automatically loads the view content from its nib using loadNibContent()
+    let view = MyHeaderTableView(frame: frame)
+
     view.fillForSection(section)
     return view
   }

README.md

@@ -297,17 +297,14 @@ final class MyCustomWidget: UIView, NibOwnerLoadable {
   …
   required init?(coder aDecoder: NSCoder) {
     super.init(coder: aDecoder)
-    MyCustomWidget.loadFromNib(owner: self)
-  }
-  override init(frame: CGRect) {
-    super.init(frame: frame)
+    self.loadNibContent()
   }
 }
 ```
 
 Overriding `init?(coder:)` allows your `MyCustomWidget` custom view to load its content from the associated XIB `MyCustomWidget.xib` and add it as subviews of itself.
 
-_💡 Note: overriding `init(frame:)`, even just to call `super.init(frame: frame)` might seems pointless, but seems necessary in some cases due to a strange issue with Swift and dynamic dispatch not being able to detect and call the superclass implementation all by itself: I've sometimes seen crashes when not implementing it explicitly, so better safe than sorry._
+_💡 Note: it is also possible to override `init(frame:)`, in order to be able to create an instance of that view programatically and call `loadNibContent()` to fill with views if needed.
 
 ## 3b. Instantiating a `NibLoadable` view
 
@@ -322,8 +319,6 @@ let view3 = NibBasedRootView.loadFromNib() // and another one
 …
 ```
 
-> 💡 You could also use `MyCustomWidget.loadFromNib()` on a `NibOwnerLoadable` — the same way we just did on `NibLoadable` views above — to load them by code if needs be too.
-
 ---
 
 

Sources/View/NibOwnerLoadable.swift

@@ -34,31 +34,24 @@ public extension NibOwnerLoadable {
 
 public extension NibOwnerLoadable where Self: UIView {
   /**
-   Returns a `UIView` object instantiated from nib
-
-   - parameter owner: The instance of the view which will be your File's Owner
-                      (and to which you want to add the XIB's views as subviews).
-                      Defaults to a brand new instance if not provided.
-   - returns: A `NibOwnLoadable`, `UIView` instance
+   Adds content loaded from the nib to the end of the receiver's list of subviews and adds constraints automatically.
    */
-  @discardableResult
-  static func loadFromNib(owner: Self = Self()) -> Self {
+  func loadNibContent() {
     let layoutAttributes: [NSLayoutAttribute] = [.top, .leading, .bottom, .trailing]
-    for view in nib.instantiate(withOwner: owner, options: nil) {
+    for view in Self.nib.instantiate(withOwner: self, options: nil) {
       if let view = view as? UIView {
         view.translatesAutoresizingMaskIntoConstraints = false
-        owner.addSubview(view)
+        self.addSubview(view)
         layoutAttributes.forEach { attribute in
-          owner.addConstraint(NSLayoutConstraint(item: view,
+          self.addConstraint(NSLayoutConstraint(item: view,
             attribute: attribute,
             relatedBy: .equal,
-            toItem: owner,
+            toItem: self,
             attribute: attribute,
             multiplier: 1,
             constant: 0.0))
         }
       }
     }
-    return owner
   }
 }