feat: improve lost focus behavior.

demo/Ursa.Demo/Pages/TagInputDemo.axaml

@@ -21,7 +21,7 @@
         <u:TagInput
             Margin="20"
             AllowDuplicates="False"
-            CleanLostFocus="true"
+            LostFocusBehavior="Clear"
             Separator="-"
             Tags="{Binding DistinctTags}" />
         <ListBox ItemsSource="{Binding DistinctTags}" />

src/Ursa/Controls/TagInput/LostFocusBehavior.cs

@@ -0,0 +1,8 @@
+namespace Ursa.Controls;
+
+public enum LostFocusBehavior
+{
+    None,
+    Add,
+    Clear,
+}

src/Ursa/Controls/TagInput/TagInput.cs

@@ -60,9 +60,14 @@ public class TagInput : TemplatedControl
 
     private void OnTextBox_LostFocus(object? sender, RoutedEventArgs e)
     {
-        if(CleanLostFocus)
+        switch (LostFocusBehavior)
         {
+            case LostFocusBehavior.Add:
+                AddTags();
+                break;
+            case LostFocusBehavior.Clear:
                 _textBox.Text = "";
+                break;
         }
     }
 
@@ -95,13 +100,13 @@ public class TagInput : TemplatedControl
         set => SetValue(SeparatorProperty, value);
     }
 
-    public static readonly StyledProperty<bool> CleanLostFocusProperty = AvaloniaProperty.Register<TagInput, bool>(
+    public static readonly StyledProperty<LostFocusBehavior> LostFocusBehaviorProperty = AvaloniaProperty.Register<TagInput, LostFocusBehavior>(
-        nameof(CleanLostFocus), defaultValue: false);
+        nameof(LostFocusBehavior));
 
-    public bool CleanLostFocus
+    public LostFocusBehavior LostFocusBehavior
     {
-        get => GetValue(CleanLostFocusProperty);
+        get => GetValue(LostFocusBehaviorProperty);
-        set => SetValue(CleanLostFocusProperty, value);
+        set => SetValue(LostFocusBehaviorProperty, value);
     }
 
 
@@ -222,8 +227,26 @@ public class TagInput : TemplatedControl
     {
         if (args.Key == Key.Enter)
         {
-            if (_textBox.Text?.Length > 0)
+            AddTags();
+        }
+        else if (args.Key == Key.Delete || args.Key == Key.Back)
         { 
+            if (string.IsNullOrEmpty(_textBox.Text)||_textBox.Text?.Length == 0)
+            {
+                if (Tags.Count == 0)
+                {
+                    return;
+                }
+                int index = Items.Count - 2;
+                // Items.RemoveAt(index);
+                Tags.RemoveAt(index);
+            }
+        }
+    }
+    
+    private void AddTags()
+    {
+        if (!(_textBox.Text?.Length > 0)) return;
         string[] values;
         if (!string.IsNullOrEmpty(Separator))
         {
@@ -247,21 +270,6 @@ public class TagInput : TemplatedControl
 
         _textBox.Text = "";
     }
-        }
-        else if (args.Key == Key.Delete || args.Key == Key.Back)
-        { 
-            if (string.IsNullOrEmpty(_textBox.Text)||_textBox.Text?.Length == 0)
-            {
-                if (Tags.Count == 0)
-                {
-                    return;
-                }
-                int index = Items.Count - 2;
-                // Items.RemoveAt(index);
-                Tags.RemoveAt(index);
-            }
-        }
-    }
 
     public void Close(object o)
     {