Merge pull request #18 from urbn/Layout_activateWithPriority

Layout - Activate w/ Priority
urbn · Dec 14, 2017 · 3194b05 · 3194b05
2 parents 2d6fd8a + f7378a9
commit 3194b05
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Showing 6 changed files with 67 additions and 7 deletions.
diff --git a/Example/Podfile.lock b/Example/Podfile.lock
@@ -1,5 +1,5 @@
 PODS:
-  - URBNSwiftyConvenience (0.4.1)
+  - URBNSwiftyConvenience (0.4.2)
 
 DEPENDENCIES:
   - URBNSwiftyConvenience (from `../`)
@@ -9,7 +9,7 @@ EXTERNAL SOURCES:
     :path: ../
 
 SPEC CHECKSUMS:
-  URBNSwiftyConvenience: 37576ec8ddd157cf5b747df482de1170c623dc58
+  URBNSwiftyConvenience: 717e90f54a313fbb998ea705707e9801edc47f37
 
 PODFILE CHECKSUM: b1a00df3b001c7558afb1929e95f3522d9d92a6b
 

diff --git a/Example/Pods/Local Podspecs/URBNSwiftyConvenience.podspec.json b/Example/Pods/Local Podspecs/URBNSwiftyConvenience.podspec.json
diff --git a/Example/Pods/Manifest.lock b/Example/Pods/Manifest.lock
diff --git a/Example/Pods/Target Support Files/URBNSwiftyConvenience/Info.plist b/Example/Pods/Target Support Files/URBNSwiftyConvenience/Info.plist
diff --git a/Example/URBNSwiftyConvenience/ViewController.swift b/Example/URBNSwiftyConvenience/ViewController.swift
@@ -91,6 +91,14 @@ class ViewController: UIViewController {
             animateBorder.widthAnchor.constraint(equalToConstant: 300).isActive = true
             animateBorder.topAnchor.constraint(equalTo: clearBorder.bottomAnchor, constant: 40).isActive = true
         }
+
+        let constraintPriorityTestView = UIView()
+        constraintPriorityTestView.backgroundColor = .blue
+        view.addSubviewsWithNoConstraints(constraintPriorityTestView)
+        constraintPriorityTestView.topAnchor.constraint(equalTo: view.topAnchor).activate(withPriority: .defaultLow)
+        constraintPriorityTestView.leftAnchor.constraint(equalTo: view.leftAnchor).activate(withPriority: .defaultHigh + 1)
+        constraintPriorityTestView.widthAnchor.constraint(equalToConstant: 42.0).activate(withPriority: .required)
+        constraintPriorityTestView.heightAnchor.constraint(equalToConstant: 42.0).activate(withPriority: ConstraintPriority(UILayoutPriorityDefaultHigh - 1))
     }
 
     override func viewDidAppear(_ animated: Bool) {

diff --git a/URBNSwiftyConvenience/Classes/LayoutConvenience.swift b/URBNSwiftyConvenience/Classes/LayoutConvenience.swift
@@ -135,3 +135,55 @@ public extension UIStackView {
         }
     }
 }
+
+// TODO: Refactor out when we move to swifty 4
+//       Also we could adopt add & subtract capability similar to - https://useyourloaf.com/blog/easier-swift-layout-priorities/
+@available(swift, obsoleted: 4.0)
+public struct ConstraintPriority: RawRepresentable {
+
+    public static let defaultLow: ConstraintPriority = ConstraintPriority(UILayoutPriorityDefaultLow)
+    public static let defaultHigh: ConstraintPriority = ConstraintPriority(UILayoutPriorityDefaultHigh)
+    public static let required: ConstraintPriority = ConstraintPriority(UILayoutPriorityRequired)
+    public static let fittingSizeLevel: ConstraintPriority = ConstraintPriority(UILayoutPriorityFittingSizeLevel)
+
+    public var rawValue: Float
+
+    public init(_ rawValue: Float) {
+        self.rawValue = rawValue
+    }
+
+    public init(rawValue: Float) {
+        self.rawValue = rawValue
+    }
+}
+
+extension ConstraintPriority: Equatable, Hashable {
+    public var hashValue: Int {
+        return rawValue.hashValue
+    }
+
+    public static func == (lhs: ConstraintPriority, rhs: ConstraintPriority) -> Bool {
+        return lhs.rawValue == rhs.rawValue
+    }
+}
+
+public extension ConstraintPriority {
+    static func +(lhs: ConstraintPriority, rhs: Float) -> ConstraintPriority {
+        return ConstraintPriority(lhs.rawValue + rhs)
+    }
+
+    static func -(lhs: ConstraintPriority, rhs: Float) -> ConstraintPriority {
+        return ConstraintPriority(lhs.rawValue - rhs)
+    }
+}
+
+
+public extension NSLayoutConstraint {
+
+    // TODO: Refactor out when we move to swifty 4
+    @available(swift, obsoleted: 4.0)
+    public func activate(withPriority constraintPriority: ConstraintPriority) {
+        self.priority = constraintPriority.rawValue
+        isActive = true
+    }
+}