Fix TextBox horizontal scrollbar position when VerticalContentAlignment is set to Top

Author: database64128

src/MainDemo.Wpf/Fields.xaml

@@ -340,12 +340,14 @@
 
           <TextBox Height="100"
                    VerticalAlignment="Top"
+                   VerticalContentAlignment="Top"
                    materialDesign:HintAssist.Hint="This is a text area"
                    AcceptsReturn="True"
                    IsEnabled="{Binding Path=IsChecked, ElementName=MaterialDesignOutlinedTextBoxEnabledComboBox}"
                    Style="{StaticResource MaterialDesignOutlinedTextBox}"
-                   TextWrapping="Wrap"
-                   VerticalScrollBarVisibility="Auto" />
+                   TextWrapping="NoWrap"
+                   VerticalScrollBarVisibility="Auto"
+                   HorizontalScrollBarVisibility="Auto" />
         </StackPanel>
       </smtx:XamlDisplay>
 

src/MaterialDesignThemes.Wpf/Themes/MaterialDesignTheme.TextBox.xaml

@@ -133,7 +133,7 @@
 
                 <Grid x:Name="ContentGrid"
                       MinHeight="16"
-                      VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
+                      VerticalAlignment="Stretch">
                   <Grid.ColumnDefinitions>
                     <ColumnDefinition Width="Auto" />
                     <ColumnDefinition Width="Auto" />
@@ -156,7 +156,7 @@
                   <ScrollViewer x:Name="PART_ContentHost"
                                 Grid.Column="2"
                                 HorizontalAlignment="Stretch"
-                                VerticalAlignment="Center"
+                                VerticalAlignment="Stretch"
                                 HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                                 VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                                 Panel.ZIndex="1"
@@ -171,7 +171,7 @@
                   <wpf:SmartHint x:Name="Hint"
                                  Grid.Column="1"
                                  Grid.ColumnSpan="3"
-                                 VerticalAlignment="Center"
+                                 VerticalAlignment="Stretch"
                                  HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
                                  VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
                                  FloatingOffset="{TemplateBinding wpf:HintAssist.FloatingOffset}"