add observer, notify on ClearButttonTapped to set state value in Deci…

FreeAPS/Sources/Modules/AddCarbs/View/AddCarbsRootView.swift

@@ -57,11 +57,7 @@ extension AddCarbs {
                     }
                     HStack {
                         Text("Note").foregroundColor(.secondary)
-                        TextField("", text: $state.note).multilineTextAlignment(.trailing)
-                        if isFocused {
-                            Button { isFocused = false } label: { Image(systemName: "keyboard.chevron.compact.down") }
-                                .controlSize(.mini)
-                        }
+                        RightAdjustedTextField(text: $state.note, textAlignment: .right)
                     }.focused($isFocused)
                     HStack {
                         Button {

FreeAPS/Sources/Views/DecimalTextField.swift

@@ -1,4 +1,5 @@
 import Combine
+import Foundation
 import SwiftUI
 
 struct DecimalTextField: UIViewRepresentable {
@@ -86,6 +87,8 @@ struct DecimalTextField: UIViewRepresentable {
         }
 
         private(set) var isEditing = false
+        private(set) var _beganEditing = false
+        private(set) var _rightAlign = true
         private var editingCancellable: AnyCancellable?
 
         func resetEditing() {
@@ -134,20 +137,75 @@ struct DecimalTextField: UIViewRepresentable {
         ) {
             // Format value with formatter at End Editing
             textField.text = parent.formatter.string(for: parent.value)
+            if textField.text == "0"
+            {
+                textField.text = ""
+            }
             isEditing = false
+            NotificationBroadcaster.shared.removeListeners(for: "ClearButtonTappedObserver")
+        }
+
+        func textFieldDidBeginEditing(_: UITextField) {
+            _beganEditing =
+                true // if we change cursor position here (with DispatchQueue), cursor jumps ; instead, do in DidChangeSelection
+            NotificationBroadcaster.shared.register(event: "ClearButtonTappedObserver") { [self] _ in
+                clearButtonTappedDidUpdate(object: self)
+            }
+        }
+
+        func textFieldDidChangeSelection(_ textField: UITextField) {
+            if _beganEditing {
+                _beganEditing = false
+                if _rightAlign {
+                    let position = textField.endOfDocument
+                    textField.selectedTextRange = textField.textRange(from: position, to: position)
+                }
+            }
+        }
+
+        func clearButtonTappedDidUpdate(object _: Any) {
+            parent.value = 0
         }
     }
 }
 
+// MARK: Singleton NotificationBroadcaster class
+
+class NotificationBroadcaster {
+    static let shared = NotificationBroadcaster()
+
+    private var listeners: [String: [(Any) -> Void]] = [:]
+
+    func register(event: String, listener: @escaping (Any) -> Void) {
+        if listeners[event] == nil {
+            listeners[event] = []
+        }
+        listeners[event]?.append(listener)
+    }
+
+    func notify(event: String, object: Any?) {
+        listeners[event]?.forEach { $0(object ?? ()) }
+    }
+
+    func removeListeners(for event: String) {
+        listeners[event] = nil
+    }
+}
+
 // MARK: extension for done button
 
 extension UITextField {
+    private var broadcaster: NotificationBroadcaster {
+        NotificationBroadcaster.shared
+    }
+
     @objc func doneButtonTapped(button _: UIBarButtonItem) {
         resignFirstResponder()
     }
 
     @objc func clearButtonTapped(button _: UIBarButtonItem) {
         text = ""
+        broadcaster.notify(event: "ClearButtonTappedObserver", object: self)
     }
 }
 
@@ -158,3 +216,95 @@ extension UIApplication {
         sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
     }
 }
+
+// MARK: RightAdjustedTextField UITextField implementation
+
+struct RightAdjustedTextField: UIViewRepresentable {
+    @Binding var text: String
+    var textAlignment: NSTextAlignment
+
+    class Coordinator: NSObject, UITextFieldDelegate {
+        var parent: RightAdjustedTextField
+
+        init(parent: RightAdjustedTextField) {
+            self.parent = parent
+        }
+
+        // Position cursor at end of text
+        func textFieldDidBeginEditing(_ textField: UITextField) {
+            DispatchQueue.main.async {
+                let endPosition = textField.endOfDocument
+                textField.selectedTextRange = textField.textRange(from: endPosition, to: endPosition)
+            }
+            NotificationBroadcaster.shared.register(event: "ClearButtonTappedObserver") { [self] _ in
+                clearButtonTappedDidUpdate(object: self)
+            }
+        }
+
+        func textFieldDidEndEditing(
+            _ textField: UITextField,
+            reason _: UITextField.DidEndEditingReason
+        ) {
+            textField.text = parent.text
+            NotificationBroadcaster.shared.removeListeners(for: "ClearButtonTappedObserver")
+        }
+
+        func textFieldShouldReturn(_ textField: UITextField) -> Bool {
+            textField.resignFirstResponder()
+            return true
+        }
+
+        func clearButtonTappedDidUpdate(object _: Any) {
+            parent.text = ""
+        }
+
+        @objc func textFieldEditingChanged(_ textField: UITextField) {
+            parent.text = textField.text ?? ""
+        }
+    }
+
+    func makeCoordinator() -> Coordinator {
+        Coordinator(parent: self)
+    }
+
+    func makeUIView(context: Context) -> UITextField {
+        let textField = UITextField()
+        textField.delegate = context.coordinator
+        textField.translatesAutoresizingMaskIntoConstraints = false
+        textField.setContentHuggingPriority(.defaultLow, for: .horizontal)
+        textField.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
+        textField.textAlignment = textAlignment
+        textField.addTarget(context.coordinator, action: #selector(Coordinator.textFieldEditingChanged(_:)), for: .editingChanged)
+        let toolBar = UIToolbar(frame: CGRect(
+            x: 0,
+            y: 0,
+            width: textField.frame.size.width,
+            height: 44
+        ))
+        let clearButton = UIBarButtonItem(
+            title: NSLocalizedString("Clear", comment: "Clear button"),
+            style: .plain,
+            target: self,
+            action: #selector(textField.clearButtonTapped(button:))
+        )
+        let doneButton = UIBarButtonItem(
+            title: NSLocalizedString("Done", comment: "Done button"),
+            style: .done,
+            target: self,
+            action: #selector(textField.doneButtonTapped(button:))
+        )
+        let space = UIBarButtonItem(
+            barButtonSystemItem: UIBarButtonItem.SystemItem.flexibleSpace,
+            target: nil,
+            action: nil
+        )
+        toolBar.setItems([clearButton, space, doneButton], animated: true)
+        textField.inputAccessoryView = toolBar
+        return textField
+    }
+
+    func updateUIView(_ uiView: UITextField, context _: Context) {
+        uiView.text = text
+        uiView.textAlignment = textAlignment
+    }
+}