init

src/Avalonia.Controls/TextBox.cs

@@ -14,6 +14,7 @@ using Avalonia.Interactivity;
 using Avalonia.Media;
 using Avalonia.Metadata;
 using Avalonia.Data;
+using Avalonia.Layout;
 using Avalonia.Utilities;
 
 namespace Avalonia.Controls
@@ -72,6 +73,18 @@ namespace Avalonia.Controls
         public static readonly StyledProperty<TextAlignment> TextAlignmentProperty =
             TextBlock.TextAlignmentProperty.AddOwner<TextBox>();
 
+        /// <summary>
+        /// Defines the <see cref="HorizontalAlignment"/> property.
+        /// </summary>
+        public static readonly StyledProperty<HorizontalAlignment> HorizontalContentAlignmentProperty =
+            AvaloniaProperty.Register<TextBox, HorizontalAlignment>(nameof(HorizontalContentAlignment));
+
+        /// <summary>
+        /// Defines the <see cref="VerticalAlignment"/> property.
+        /// </summary>
+        public static readonly StyledProperty<VerticalAlignment> VerticalContentAlignmentProperty =
+            AvaloniaProperty.Register<TextBox, VerticalAlignment>(nameof(VerticalContentAlignment));
+
         public static readonly StyledProperty<TextWrapping> TextWrappingProperty =
             TextBlock.TextWrappingProperty.AddOwner<TextBox>();
 
@@ -262,6 +275,17 @@ namespace Avalonia.Controls
             }
         }
 
+        public HorizontalAlignment HorizontalContentAlignment
+        {
+            get { return GetValue(HorizontalContentAlignmentProperty); }
+            set { SetValue(HorizontalContentAlignmentProperty, value); }
+        }
+        public VerticalAlignment VerticalContentAlignment
+        {
+            get { return GetValue(VerticalContentAlignmentProperty); }
+            set { SetValue(VerticalContentAlignmentProperty, value); }
+        }
+
         public TextAlignment TextAlignment
         {
             get { return GetValue(TextAlignmentProperty); }

src/Avalonia.Themes.Default/TextBox.xaml

@@ -15,6 +15,7 @@
           <DockPanel Margin="{TemplateBinding Padding}">
 
             <TextBlock Name="floatingWatermark"
+                       HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                        Foreground="{DynamicResource ThemeAccentBrush}"
                        FontSize="{DynamicResource FontSizeSmall}"
                        Text="{TemplateBinding Watermark}"
@@ -37,9 +38,13 @@
                 <Panel>
                   <TextBlock Name="watermark"
                              Opacity="0.5"
+                             HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
+                             VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                              Text="{TemplateBinding Watermark}"
                              IsVisible="{TemplateBinding Text, Converter={x:Static StringConverters.IsNullOrEmpty}}"/>
                   <TextPresenter Name="PART_TextPresenter"
+                                 HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
+                                 VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                                  Text="{TemplateBinding Text, Mode=TwoWay}"
                                  CaretIndex="{TemplateBinding CaretIndex}"
                                  SelectionStart="{TemplateBinding SelectionStart}"