add "PasswordBox" support "ButtonsAlignment"

add "MetroButtonPasswordBox" support "TextBoxHelper.ButtonsAlignment"

Author: waleswood

src/MahApps.Metro/MahApps.Metro/Styles/Controls.PasswordBox.xaml

@@ -369,7 +369,7 @@
                                 SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
                         <Grid x:Name="PART_InnerGrid" Margin="2">
                             <Grid.ColumnDefinitions>
-                                <ColumnDefinition Width="*" />
+                                <ColumnDefinition Width="Auto" />
                                 <ColumnDefinition Width="Auto" />
                                 <ColumnDefinition x:Name="ButtonColumn" Width="Auto" />
                             </Grid.ColumnDefinitions>
@@ -450,6 +450,13 @@
                                 Visibility="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(Controls:ControlsHelper.DisabledVisualElementVisibility), Mode=OneWay}" />
                     </Grid>
                     <ControlTemplate.Triggers>
+                        <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Path=(Controls:TextBoxHelper.ButtonsAlignment)}" Value="Left">
+                            <Setter TargetName="ButtonColumn" Property="Width" Value="*" />
+                            <Setter TargetName="PART_ClearText" Property="Grid.Column" Value="0" />
+                            <Setter TargetName="PART_ContentHost" Property="Grid.Column" Value="1" />
+                            <Setter TargetName="PART_Message" Property="Grid.Column" Value="1" />
+                        </DataTrigger>
+
                         <DataTrigger Binding="{Binding RelativeSource={RelativeSource Self}, Path=Password, Mode=OneWay}" Value="">
                             <Setter TargetName="PART_Message" Property="Visibility" Value="Visible" />
                         </DataTrigger>
@@ -468,6 +475,15 @@
                             </MultiDataTrigger.ExitActions>
                         </MultiDataTrigger>
 
+                        <MultiDataTrigger>
+                            <MultiDataTrigger.Conditions>
+                                <Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=(Controls:TextBoxHelper.ButtonsAlignment)}" Value="Right" />
+                                <Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=(Controls:TextBoxHelper.TextButton)}" Value="False" />
+                            </MultiDataTrigger.Conditions>
+                            <Setter TargetName="PART_ContentHost" Property="Grid.ColumnSpan" Value="2" />
+                            <Setter TargetName="PART_Message" Property="Grid.ColumnSpan" Value="2" />
+                        </MultiDataTrigger>
+
                         <Trigger Property="IsMouseOver" Value="True">
                             <Setter TargetName="Base" Property="BorderBrush" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(Controls:ControlsHelper.MouseOverBorderBrush)}" />
                         </Trigger>