Add "inputToolbarDoneClosure"， Improve "willUpdateClosure"

SwiftForms/cells/base/FormBaseCell.swift

@@ -73,6 +73,9 @@ open class FormBaseCell: UITableViewCell {
     }
 
     internal func handleDoneAction(_: UIBarButtonItem) {
+        if let inputToolbarDoneClosure = rowDescriptor?.configuration.cell.inputToolbarDoneClosure {
+            inputToolbarDoneClosure(self)
+        }
         firstResponderElement()?.resignFirstResponder()
     }
 

SwiftForms/descriptors/FormRowDescriptor.swift

@@ -47,9 +47,10 @@ public final class FormRowDescriptor {
         public var placeholder:              String?
         public var showsInputToolbar:        Bool
         public var required:                 Bool
-        public var willUpdateClosure:        ((FormRowDescriptor) -> Void)?
+        public var willUpdateClosure:        ((FormRowDescriptor, AnyObject?, inout AnyObject?) -> Void)?
         public var didUpdateClosure:         ((FormRowDescriptor) -> Void)?
         public var visualConstraintsClosure: ((FormBaseCell) -> [String])?
+        public var inputToolbarDoneClosure:  ((FormBaseCell) -> Void)?
 
         public init() {
             cellClass = nil
@@ -60,6 +61,7 @@ public final class FormRowDescriptor {
             willUpdateClosure = nil
             didUpdateClosure = nil
             visualConstraintsClosure = nil
+            inputToolbarDoneClosure = nil
         }
     }
 
@@ -128,14 +130,24 @@ public final class FormRowDescriptor {
 
     public var title: String?
 
+    private var _value: AnyObject?
     public var value: AnyObject? {
-        willSet {
-            guard let willUpdateBlock = configuration.cell.willUpdateClosure else { return }
-            willUpdateBlock(self)
+        set {
+            if newValue !== _value {
+                var newV = newValue
+                if let willUpdateBlock = configuration.cell.willUpdateClosure {
+                    willUpdateBlock(self, _value, &newV)
+                }
+
+                _value = newV
+
+                if let didUpdateBlock = configuration.cell.didUpdateClosure {
+                    didUpdateBlock(self)
+                }
+            }
         }
-        didSet {
-            guard let didUpdateBlock = configuration.cell.didUpdateClosure else { return }
-            didUpdateBlock(self)
+        get {
+            return _value
         }
     }