Merge pull request quicoli#50 from mitchcapper/selection_finishing_pr…

…e_event_pr Provide a PreSelectionFinished event with the cause (Allows control of enter,tab,escape etc actions)
ninhpham96 · Feb 25, 2022 · 965384c · 965384c
2 parents 5fc5932 + 39700cc
commit 965384c
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Showing 3 changed files with 56 additions and 20 deletions.
diff --git a/AutoCompleteTextBox/AutoCompleteTextBox/Editors/AutoCompleteComboBox.cs b/AutoCompleteTextBox/AutoCompleteTextBox/Editors/AutoCompleteComboBox.cs
@@ -356,7 +356,7 @@ private void ItemsSelector_PreviewMouseDown(object sender, MouseButtonEventArgs
             if (!ItemsSelector.Items.Contains(((FrameworkElement)e.OriginalSource)?.DataContext))
                 return;
             ItemsSelector.SelectedItem = ((FrameworkElement)e.OriginalSource)?.DataContext;
-            OnSelectionAdapterCommit();
+            OnSelectionAdapterCommit(SelectionAdapter.EventCause.ItemClicked);
             e.Handled = true;
         }
         private void AutoCompleteComboBox_GotFocus(object sender, RoutedEventArgs e)
@@ -443,18 +443,29 @@ private void OnPopupClosed(object sender, EventArgs e)
         {
             if (!_selectionCancelled)
             {
-                OnSelectionAdapterCommit();
+                OnSelectionAdapterCommit(SelectionAdapter.EventCause.PopupClosed);
             }
         }
 
         private void OnPopupOpened(object sender, EventArgs e)
         {
             _selectionCancelled = false;
             ItemsSelector.SelectedItem = SelectedItem;
-        }
-
-        private void OnSelectionAdapterCancel()
-        {
+        }
+
+        public event EventHandler<SelectionAdapter.PreSelectionAdapterFinishArgs> PreSelectionAdapterFinish;
+        private bool PreSelectionEventSomeoneHandled(SelectionAdapter.EventCause cause, bool is_cancel) {
+            if (PreSelectionAdapterFinish == null)
+                return false;
+            var args = new SelectionAdapter.PreSelectionAdapterFinishArgs { cause = cause, is_cancel = is_cancel };
+            PreSelectionAdapterFinish?.Invoke(this, args);
+            return args.handled;
+
+        }
+        private void OnSelectionAdapterCancel(SelectionAdapter.EventCause cause)
+        {
+            if (PreSelectionEventSomeoneHandled(cause, true))
+                return;
             _isUpdatingText = true;
             Editor.Text = SelectedItem == null ? Filter : GetDisplayText(SelectedItem);
             Editor.SelectionStart = Editor.Text.Length;
@@ -464,8 +475,11 @@ private void OnSelectionAdapterCancel()
             _selectionCancelled = true;
         }
 
-        private void OnSelectionAdapterCommit()
-        {
+        private void OnSelectionAdapterCommit(SelectionAdapter.EventCause cause)
+        {
+            if (PreSelectionEventSomeoneHandled(cause, false))
+                return;
+
             if (ItemsSelector.SelectedItem != null)
             {
                 SelectedItem = ItemsSelector.SelectedItem;

diff --git a/AutoCompleteTextBox/AutoCompleteTextBox/Editors/AutoCompleteTextBox.cs b/AutoCompleteTextBox/AutoCompleteTextBox/Editors/AutoCompleteTextBox.cs
@@ -324,7 +324,7 @@ private void ItemsSelector_PreviewMouseDown(object sender, MouseButtonEventArgs
             if (!ItemsSelector.Items.Contains(((FrameworkElement)e.OriginalSource)?.DataContext))
                 return;
             ItemsSelector.SelectedItem = ((FrameworkElement)e.OriginalSource)?.DataContext;
-            OnSelectionAdapterCommit();
+            OnSelectionAdapterCommit(SelectionAdapter.EventCause.MouseDown);
             e.Handled = true;
         }
         private void AutoCompleteTextBox_GotFocus(object sender, RoutedEventArgs e)
@@ -411,7 +411,7 @@ private void OnPopupClosed(object sender, EventArgs e)
         {
             if (!_selectionCancelled)
             {
-                OnSelectionAdapterCommit();
+                OnSelectionAdapterCommit(SelectionAdapter.EventCause.PopupClosed);
             }
         }
 
@@ -421,19 +421,35 @@ private void OnPopupOpened(object sender, EventArgs e)
             ItemsSelector.SelectedItem = SelectedItem;
         }
 
-        private void OnSelectionAdapterCancel()
-        {
+        private void OnSelectionAdapterCancel(SelectionAdapter.EventCause cause)
+        {
+            if (PreSelectionEventSomeoneHandled(cause, true))
+                return;
+
             _isUpdatingText = true;
             Editor.Text = SelectedItem == null ? Filter : GetDisplayText(SelectedItem);
             Editor.SelectionStart = Editor.Text.Length;
             Editor.SelectionLength = 0;
             _isUpdatingText = false;
             IsDropDownOpen = false;
             _selectionCancelled = true;
-        }
 
-        private void OnSelectionAdapterCommit()
+        }
+
+        public event EventHandler<SelectionAdapter.PreSelectionAdapterFinishArgs> PreSelectionAdapterFinish;
+        private bool PreSelectionEventSomeoneHandled(SelectionAdapter.EventCause cause, bool is_cancel) {
+            if (PreSelectionAdapterFinish == null)
+                return false;
+            var args = new SelectionAdapter.PreSelectionAdapterFinishArgs { cause = cause, is_cancel = is_cancel };
+            PreSelectionAdapterFinish?.Invoke(this, args);
+            return args.handled;
+
+        }
+        private void OnSelectionAdapterCommit(SelectionAdapter.EventCause cause)
         {
+            if (PreSelectionEventSomeoneHandled(cause, false))
+                return;
+
             if (ItemsSelector.SelectedItem != null)
             {
                 SelectedItem = ItemsSelector.SelectedItem;

diff --git a/AutoCompleteTextBox/AutoCompleteTextBox/Editors/SelectionAdapter.cs b/AutoCompleteTextBox/AutoCompleteTextBox/Editors/SelectionAdapter.cs
@@ -6,6 +6,11 @@ namespace AutoCompleteTextBox.Editors
 {
     public class SelectionAdapter
     {
+        public class PreSelectionAdapterFinishArgs {
+            public EventCause cause;
+            public bool is_cancel;
+            public bool handled;
+        }
 
         #region "Fields"
         #endregion
@@ -22,9 +27,10 @@ public SelectionAdapter(Selector selector)
 
         #region "Events"
 
-        public delegate void CancelEventHandler();
+        public enum EventCause { Other, PopupClosed, ItemClicked, EnterPressed, EscapePressed, TabPressed, MouseDown}
+        public delegate void CancelEventHandler(EventCause cause);
 
-        public delegate void CommitEventHandler();
+        public delegate void CommitEventHandler(EventCause cause);
 
         public delegate void SelectionChangedEventHandler();
 
@@ -52,15 +58,15 @@ public void HandleKeyDown(KeyEventArgs key)
                     DecrementSelection();
                     break;
                 case Key.Enter:
-                    Commit?.Invoke();
+                    Commit?.Invoke(EventCause.EnterPressed);
 
                     break;
                 case Key.Escape:
-                    Cancel?.Invoke();
+                    Cancel?.Invoke(EventCause.EscapePressed);
 
                     break;
                 case Key.Tab:
-                    Commit?.Invoke();
+                    Commit?.Invoke(EventCause.TabPressed);
 
                     break;
                 default:
@@ -104,7 +110,7 @@ private void OnSelectorMouseDown(object sender, MouseButtonEventArgs e)
             // and list is scrolled up or down til the end.
             if (e.OriginalSource.GetType() != typeof(RepeatButton))
             {
-                Commit?.Invoke();
+                Commit?.Invoke(EventCause.MouseDown);
                 e.Handled = true;
             }
         }