From 5b015d54dc09c4ae1cee7d7f41fbbc14a5fe96ba Mon Sep 17 00:00:00 2001
From: Zhang Dian <54255897+zdpcdt@users.noreply.github.com>
Date: Thu, 19 Mar 2026 17:27:50 +0800
Subject: [PATCH] Update Placeholder properties to use TextBox as owner in
 NumericUpDown & ComboBox (#20929)

* feat: update PlaceholderText and PlaceholderForeground properties to use TextBox as owner in NumericUpDown and ComboBox.

* chore: disable warning.
---
 src/Avalonia.Controls/ComboBox.cs                    | 4 ++--
 src/Avalonia.Controls/NumericUpDown/NumericUpDown.cs | 4 +++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/Avalonia.Controls/ComboBox.cs b/src/Avalonia.Controls/ComboBox.cs
index c977ca0a38..eb1eab5856 100644
--- a/src/Avalonia.Controls/ComboBox.cs
+++ b/src/Avalonia.Controls/ComboBox.cs
@@ -62,13 +62,13 @@ namespace Avalonia.Controls
         /// Defines the <see cref="PlaceholderText"/> property.
         /// </summary>
         public static readonly StyledProperty<string?> PlaceholderTextProperty =
-            AvaloniaProperty.Register<ComboBox, string?>(nameof(PlaceholderText));
+            TextBox.PlaceholderTextProperty.AddOwner<ComboBox>();
 
         /// <summary>
         /// Defines the <see cref="PlaceholderForeground"/> property.
         /// </summary>
         public static readonly StyledProperty<IBrush?> PlaceholderForegroundProperty =
-            AvaloniaProperty.Register<ComboBox, IBrush?>(nameof(PlaceholderForeground));
+            TextBox.PlaceholderForegroundProperty.AddOwner<ComboBox>();
 
         /// <summary>
         /// Defines the <see cref="HorizontalContentAlignment"/> property.
diff --git a/src/Avalonia.Controls/NumericUpDown/NumericUpDown.cs b/src/Avalonia.Controls/NumericUpDown/NumericUpDown.cs
index ddaa57f2f2..2f901860ba 100644
--- a/src/Avalonia.Controls/NumericUpDown/NumericUpDown.cs
+++ b/src/Avalonia.Controls/NumericUpDown/NumericUpDown.cs
@@ -112,7 +112,9 @@ namespace Avalonia.Controls
         /// Defines the <see cref="PlaceholderText"/> property.
         /// </summary>
         public static readonly StyledProperty<string?> PlaceholderTextProperty =
-            AvaloniaProperty.Register<NumericUpDown, string?>(nameof(PlaceholderText));
+#pragma warning disable AVP1013
+            TextBox.PlaceholderTextProperty.AddOwner<NumericUpDown>();
+#pragma warning restore AVP1013
 
         /// <summary>
         /// Defines the <see cref="Watermark"/> property.