clean up of stack

MVMCoreUI/Molecules/MoleculeStackView.swift

@@ -21,6 +21,10 @@ public class StackItem {
     
     init(with view: UIView, json: [AnyHashable: Any]) {
         self.view = view
+        update(with: json)
+    }
+    
+    func update(with json: [AnyHashable: Any]) {
         spacing = json.optionalCGFloatForKey("spacing")
         percentage = json["percent"] as? Int
         if let alignment = json.optionalStringForKey("verticalAlignment") {
@@ -33,33 +37,29 @@ public class StackItem {
 }
 
 public class MoleculeStackView: ViewConstrainingView {
-    var spacingBlock: ((Any) -> UIEdgeInsets)?
-    var useMargins: Bool = false
-    
     var contentView: UIView = MVMCoreUICommonViewsUtility.commonView()
     var items: [StackItem] = []
     
-    private var spacingConstraints: [NSLayoutConstraint] = []
-    
     /// For setting the direction of the stack
     var axis: NSLayoutConstraint.Axis = .vertical {
         didSet {
+            updateViewHorizontalDefaults = axis == .horizontal
             if axis != oldValue  {
                 restack()
             }
         }
     }
     
+    /// The spacing to use between each item in the stack.
     var spacing: CGFloat = 16 {
         didSet {
             if spacing != oldValue  {
-                MVMCoreDispatchUtility.performBlock(onMainThread: {
+                restack()
-                    // loop space bettwen constraints and update. skip custom ones...
-                })
             }
         }
     }
     
+    // MARK: - Helpers
     public func setAxisWithJSON(_ json: [AnyHashable: Any]?) {
         switch json?.optionalStringForKey("axis") {
         case "horizontal":
@@ -69,12 +69,20 @@ public class MoleculeStackView: ViewConstrainingView {
         }
     }
     
-    
+    public func pinView(_ view: UIView, toView: UIView, attribute: NSLayoutConstraint.Attribute, relation: NSLayoutConstraint.Relation, priority: UILayoutPriority, constant: CGFloat) {
-    public func pinView(_ view: UIView, toView: UIView, attribute: NSLayoutConstraint.Attribute, relation: NSLayoutConstraint.Relation, priority: UILayoutPriority, constant: CGFloat) -> NSLayoutConstraint {
         let constraint = NSLayoutConstraint(item: view, attribute: attribute, relatedBy: relation, toItem: toView, attribute: attribute, multiplier: 1.0, constant: constant)
         constraint.priority = priority
         constraint.isActive = true
-        return constraint
+    }
+    
+    /// Restacks the existing items.
+    func restack() {
+        MVMCoreUIStackableViewController.remove(contentView.subviews)
+        let stackItems = items
+        items.removeAll()
+        for (index, item) in stackItems.enumerated() {
+            addStackItem(item, lastItem: index == stackItems.count - 1)
+        }
     }
 
     // MARK: - Inits
@@ -87,11 +95,6 @@ public class MoleculeStackView: ViewConstrainingView {
         setWithJSON(json, delegateObject: delegateObject, additionalData: additionalData)
     }
     
-    public convenience init(withJSON json: [AnyHashable: Any]?, delegateObject: MVMCoreUIDelegateObject?, spacingBlock: ((Any) -> UIEdgeInsets)?) {
-        self.init(withJSON: json, delegateObject: delegateObject, additionalData: nil)
-        self.spacingBlock = spacingBlock
-    }
-    
     public required init?(coder aDecoder: NSCoder) {
         fatalError("init(coder:) has not been implemented")
     }
@@ -111,15 +114,18 @@ public class MoleculeStackView: ViewConstrainingView {
     
     public override func updateView(_ size: CGFloat) {
         super.updateView(size)
-        for view in subviews {
+        for item in items {
-            if let mvmView = view as? MVMCoreViewProtocol {
+            (item.view as? MVMCoreViewProtocol)?.updateView(size)
-                mvmView.updateView(size)
-            }
         }
     }
     
     // MARK: - MVMCoreUIMoleculeViewProtocol
+    public override func setAsMolecule() {
+        updateViewHorizontalDefaults = false
+    }
+    
     public override func reset() {
+        backgroundColor = .clear
         for item in items {
             if let view = item.view as? MVMCoreUIMoleculeViewProtocol {
                 view.reset?()
@@ -128,9 +134,21 @@ public class MoleculeStackView: ViewConstrainingView {
     }
     
     open override func setWithJSON(_ json: [AnyHashable: Any]?, delegateObject: MVMCoreUIDelegateObject?, additionalData: [AnyHashable: Any]?) {
+        let previousJSON = self.json
         super.setWithJSON(json, delegateObject: delegateObject, additionalData: additionalData)
-        clear()
+        MVMCoreUIStackableViewController.remove(contentView.subviews)
+
+        // If the items in the stack are the same, just update previous items instead of re-allocating.
+        var items: [StackItem]?
+        if MoleculeStackView.name(forReuse: previousJSON, delegateObject: delegateObject) == MoleculeStackView.name(forReuse: json, delegateObject: delegateObject) {
+            items = self.items
+        }
+        self.items = []
         
+        if let colorString = json?.optionalStringForKey(KeyBackgroundColor) {
+            backgroundColor = .mfGet(forHex: colorString)
+        }
+
         guard let molecules = json?.arrayForKey(KeyMolecules) as? [[String: Any]] else {
             return
         }
@@ -148,59 +166,28 @@ public class MoleculeStackView: ViewConstrainingView {
             alignVertical(.leading)
         }
         
-        // Create the molecules and set the json.
+        // Adds the molecules and sets the json.
         for (index, map) in molecules.enumerated() {
-            if let moleculeJSON = map.optionalDictionaryForKey(KeyMolecule), let molecule = MVMCoreUIMoleculeMappingObject.shared()?.createMolecule(forJSON: moleculeJSON, delegateObject: delegateObject, constrainIfNeeded: true) {
+            if let moleculeJSON = map.optionalDictionaryForKey(KeyMolecule) {
-                
+                var view: UIView?
-                addStackItem(StackItem(with: molecule, json: map), lastItem: index == molecules.count - 1)
+                if let item = items?[index] {
-                /*contentView.addSubview(molecule)
+                    (item.view as? MVMCoreUIMoleculeViewProtocol)?.setWithJSON(moleculeJSON, delegateObject: delegateObject, additionalData: additionalData)
-                molecule.translatesAutoresizingMaskIntoConstraints = false
+                    item.update(with: moleculeJSON)
-                
+                    view = item.view
-                let spacing = CGFloat(map["spacing"] as? Float ?? self.spacing)
+                    addStackItem(item, lastItem: index == molecules.count - 1)
-                let percent = map["percent"] as? Int
+                } else if let molecule = MVMCoreUIMoleculeMappingObject.shared()?.createMolecule(forJSON: moleculeJSON, delegateObject: delegateObject, constrainIfNeeded: true) {
-                let verticalAlignment = ViewConstrainingView.getAlignmentFor(map.optionalStringForKey("verticalAlignment"), defaultAlignment: (percent == nil && axis == .vertical ? UIStackView.Alignment.fill : UIStackView.Alignment.leading))
+                    view = molecule
-                let horizontalAlignment = ViewConstrainingView.getAlignmentFor(map.optionalStringForKey("horizontalAlignment"), defaultAlignment: (axis == .vertical || percent == nil ? UIStackView.Alignment.fill : UIStackView.Alignment.leading))
+                    addStackItem(StackItem(with: molecule, json: map), lastItem: index == molecules.count - 1)
-
-                if let molecule = molecule as? MVMCoreUIViewConstrainingProtocol {
-                    molecule.alignHorizontal?(horizontalAlignment)
-                    molecule.alignVertical?(verticalAlignment)
                 }
-                if axis == .vertical {
+                
-                    if index == 0 {
+                (view as? MVMCoreUIViewConstrainingProtocol)?.shouldSetHorizontalMargins?(axis == .vertical)
-                        pinView(molecule, toView: previousObject, attribute: .top, relation: .equal, priority: .required, constant: spacing)
+                (view as? MVMCoreUIViewConstrainingProtocol)?.shouldSetVerticalMargins?(false)
-                    } else {
-                        NSLayoutConstraint(pinFirstView: previousObject, toSecondView: molecule, withConstant: spacing, directionVertical: true)?.isActive = true
-                    }
-                    pinView(molecule, toView: contentView, attribute: .leading, relation: .equal, priority: .required, constant: 0)
-                    pinView(contentView, toView: molecule, attribute: .trailing, relation: .equal, priority: .required, constant: 0)
-                    if let percent = percent {
-                        molecule.heightAnchor.constraint(equalTo: contentView.heightAnchor, multiplier: CGFloat(percent)/100.0).isActive = true
-                    }
-                } else {
-                    if index == 0 {
-                        pinView(molecule, toView: previousObject, attribute: .leading, relation: .equal, priority: .required, constant: spacing)
-                    } else {
-                        NSLayoutConstraint(pinFirstView: previousObject, toSecondView: molecule, withConstant: spacing, directionVertical: false)?.isActive = true
-                    }
-                    pinView(molecule, toView: contentView, attribute: .top, relation: .equal, priority: .required, constant: 0)
-                    pinView(contentView, toView: molecule, attribute: .bottom, relation: .equal, priority: .required, constant: 0)
-                    if let percent = percent {
-                        molecule.widthAnchor.constraint(equalTo: contentView.widthAnchor, multiplier: CGFloat(percent)/100.0).isActive = true
-                    }
-                }
-                previousObject = molecule
-            }
-        }
-        if axis == .vertical {
-            pinView(contentView, toView: previousObject, attribute: .bottom, relation: .equal, priority: .required, constant: 0)
-        } else {
-            pinView(contentView, toView: previousObject, attribute: .right, relation: .equal, priority: .required, constant: 0)
-        }*/
             }
         }
     }
     
     public override static func name(forReuse molecule: [AnyHashable : Any]?, delegateObject: MVMCoreUIDelegateObject?) -> String? {
+        // This will aggregate names of molecules to make an id.
         var name = ""
         guard let molecules = molecule?.optionalArrayForKey(KeyMolecules) else {
             return name
@@ -213,21 +200,7 @@ public class MoleculeStackView: ViewConstrainingView {
         return name
     }
     
-    // MARK: - Convenience Functions
+    // MARK: - Adding to stack
-    func clear() {
-        MVMCoreUIStackableViewController.remove(contentView.subviews)
-        spacingConstraints = []
-    }
-    
-    func restack() {
-        clear()
-        let stackItems = items
-        items.removeAll()
-        for (index, item) in stackItems.enumerated() {
-            addStackItem(item, lastItem: index == stackItems.count - 1)
-        }
-    }
-    
     /// Adds the view to the stack.
     func addView(_ view: UIView, lastItem: Bool) {
         addStackItem(StackItem(with: view), lastItem: lastItem)
@@ -248,9 +221,9 @@ public class MoleculeStackView: ViewConstrainingView {
         }
         if axis == .vertical {
             if items.count == 0 {
-                spacingConstraints.append(pinView(view, toView: contentView, attribute: .top, relation: .equal, priority: .required, constant: spacing))
+                pinView(view, toView: contentView, attribute: .top, relation: .equal, priority: .required, constant: spacing)
             } else if let previousView = items.last?.view {
-                spacingConstraints.append(NSLayoutConstraint(pinFirstView: previousView, toSecondView: view, withConstant: spacing, directionVertical: true))
+                _ = NSLayoutConstraint(pinFirstView: previousView, toSecondView: view, withConstant: spacing, directionVertical: true)
             }
             pinView(view, toView: contentView, attribute: .leading, relation: .equal, priority: .required, constant: 0)
             pinView(contentView, toView: view, attribute: .trailing, relation: .equal, priority: .required, constant: 0)
@@ -263,9 +236,9 @@ public class MoleculeStackView: ViewConstrainingView {
         } else {
             if items.count == 0 {
                 // First horizontal item has no spacing by default unless told otherwise.
-                spacingConstraints.append(pinView(view, toView: contentView, attribute: .leading, relation: .equal, priority: .required, constant: stackItem.spacing ?? 0))
+                pinView(view, toView: contentView, attribute: .leading, relation: .equal, priority: .required, constant: stackItem.spacing ?? 0)
             } else if let previousView = items.last?.view {
-                spacingConstraints.append(NSLayoutConstraint(pinFirstView: previousView, toSecondView: view, withConstant: spacing, directionVertical: false))
+                _ = NSLayoutConstraint(pinFirstView: previousView, toSecondView: view, withConstant: spacing, directionVertical: false)
             }
             pinView(view, toView: contentView, attribute: .top, relation: .equal, priority: .required, constant: 0)
             pinView(contentView, toView: view, attribute: .bottom, relation: .equal, priority: .required, constant: 0)

MVMCoreUI/Molecules/MoleculeTableViewCell.swift

@@ -44,6 +44,7 @@ import UIKit
         MFStyler.setDefaultMarginsFor(self, size: size, horizontal: true, vertical: true)
         if #available(iOS 11.0, *) {
             if accessoryView != nil {
+                // Smaller left margin if accessory view.
                 var margin = directionalLayoutMargins
                 margin.trailing = 16
                 contentView.directionalLayoutMargins = margin
@@ -54,6 +55,7 @@ import UIKit
             bottomSeparatorView?.setLeftAndRightPinConstant(directionalLayoutMargins.leading)
         } else {
             if accessoryView != nil {
+                // Smaller left margin if accessory view.
                 var margin = layoutMargins
                 margin.right = 16
                 contentView.layoutMargins = margin
@@ -87,15 +89,17 @@ import UIKit
         if molecule == nil {
             if let moleculeView = MVMCoreUIMoleculeMappingObject.shared()?.createMolecule(forJSON: moleculeJSON, delegateObject: delegateObject, constrainIfNeeded: true) {
                 contentView.addSubview(moleculeView)
-                let standardConstraints = (moleculeView as? MVMCoreUIViewConstrainingProtocol)?.useStandardConstraints?() ?? true
+                var standardConstraints = true
+                if let castView = moleculeView as? MVMCoreUIViewConstrainingProtocol {
+                    standardConstraints = castView.useStandardConstraints?() ?? true
+                    castView.shouldSetHorizontalMargins?(!standardConstraints)
+                    castView.shouldSetVerticalMargins?(!standardConstraints)
+                }
                 NSLayoutConstraint.activate(Array(NSLayoutConstraint.pinView(toSuperview: moleculeView, useMargins: standardConstraints).values))
                 if standardConstraints {
                     let constraint = contentView.heightAnchor.constraint(equalToConstant: 80)
                     constraint.priority = .defaultLow
                     constraint.isActive = true
-                    if let moleculeView = moleculeView as? ViewConstrainingView {
-                        moleculeView.updateViewHorizontalDefaults = false
-                    }
                 }
                 molecule = moleculeView
             }
@@ -126,7 +130,7 @@ import UIKit
         guard let moleculeJSON = json?.optionalDictionaryForKey(KeyMolecule),
             let theClass = MVMCoreUIMoleculeMappingObject.shared()?.getMoleculeClass(withJSON: moleculeJSON, delegateObject: nil),
             let estimatedHeightFor = theClass.estimatedHeight else {
-                return 0
+                return 80
         }
         return estimatedHeightFor(moleculeJSON)
     }