From ff65f4f44197ecbd4dc1e38a88a2c05903c69268 Mon Sep 17 00:00:00 2001
From: rabbitism <dongbin@irihi.tech>
Date: Sun, 13 Jul 2025 15:32:33 +0800
Subject: [PATCH] feat: add new readonly property: LineCount. add a demo of
 consuming this property. demo will be reverted.

---
 demo/Ursa.Demo/Pages/ElasticWrapPanelDemo.axaml | 10 +++++++++-
 src/Ursa/Controls/ElasticWrapPanel.cs           | 16 ++++++++++------
 2 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/demo/Ursa.Demo/Pages/ElasticWrapPanelDemo.axaml b/demo/Ursa.Demo/Pages/ElasticWrapPanelDemo.axaml
index 10040d3..c8f9057 100644
--- a/demo/Ursa.Demo/Pages/ElasticWrapPanelDemo.axaml
+++ b/demo/Ursa.Demo/Pages/ElasticWrapPanelDemo.axaml
@@ -104,11 +104,19 @@
             <TabItem Header="Flat">
                 <TabControl>
                     <TabItem Header="Common">
-                        <u:ElasticWrapPanel IsFillHorizontal="{Binding IsFillHorizontal}"
+                        <u:ElasticWrapPanel
                                             IsFillVertical="{Binding IsFillVertical}"
                                             ItemHeight="{Binding ItemHeight}"
                                             ItemWidth="{Binding ItemWidth}"
                                             Orientation="{Binding SelectedOrientation}">
+                            <u:ElasticWrapPanel.Styles>
+                                <Style Selector="u|ElasticWrapPanel">
+                                    <Setter Property="IsFillHorizontal" Value="True" />
+                                </Style>
+                                <Style Selector="u|ElasticWrapPanel[LineCount=1]">
+                                    <Setter Property="IsFillHorizontal" Value="False" />
+                                </Style>
+                            </u:ElasticWrapPanel.Styles>
                             <Border Background="{DynamicResource SemiRed5Color}" />
                             <Border Background="{DynamicResource SemiPink5Color}" />
                             <Border Background="{DynamicResource SemiPurple5Color}" />
diff --git a/src/Ursa/Controls/ElasticWrapPanel.cs b/src/Ursa/Controls/ElasticWrapPanel.cs
index b971709..6fb71b6 100644
--- a/src/Ursa/Controls/ElasticWrapPanel.cs
+++ b/src/Ursa/Controls/ElasticWrapPanel.cs
@@ -11,10 +11,8 @@ public class ElasticWrapPanel : WrapPanel
 {
     static ElasticWrapPanel()
     {
-        IsFillHorizontalProperty.Changed.AddClassHandler<Control>(OnIsFillPropertyChanged);
-        IsFillVerticalProperty.Changed.AddClassHandler<Control>(OnIsFillPropertyChanged);
-
         AffectsMeasure<ElasticWrapPanel>(IsFillHorizontalProperty, IsFillVerticalProperty);
+        AffectsArrange<ElasticWrapPanel>(IsFillHorizontalProperty, IsFillVerticalProperty);
     }
 
     #region AttachedProperty
@@ -60,9 +58,15 @@ public class ElasticWrapPanel : WrapPanel
     public static readonly StyledProperty<bool> IsFillVerticalProperty =
         AvaloniaProperty.Register<ElasticWrapPanel, bool>(nameof(IsFillVertical));
 
-    private static void OnIsFillPropertyChanged(AvaloniaObject d, AvaloniaPropertyChangedEventArgs e)
+    private int _lineCount;
+
+    public static readonly DirectProperty<ElasticWrapPanel, int> LineCountProperty = AvaloniaProperty.RegisterDirect<ElasticWrapPanel, int>(
+        nameof(LineCount), o => o.LineCount);
+
+    public int LineCount
     {
-        (d as ElasticWrapPanel)?.InvalidateMeasure();
+        get => _lineCount;
+        private set => SetAndRaise(LineCountProperty, ref _lineCount, value);
     }
 
     #endregion
@@ -376,7 +380,7 @@ public class ElasticWrapPanel : WrapPanel
                 lineUIEles.Clear();
             }
         }
-
+        LineCount = lineUVCollection.Count;
         lineUVCollection.ForEach(col => col.Dispose());
         lineUVCollection.Clear();
         return finalSize;