Develop Reference

WPF: Binding to "HorizontalAlignment" Property of Grid

I am writing a chatclient and my messages get displayed in a listbox. In the xaml my listbox is set up like this:
<ListBox x:Name="list_chat" Background="{x:Null}" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch" Margin="256,0,0,64" BorderThickness="0" BorderBrush="{x:Null}" Foreground="White" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ScrollViewer.VerticalScrollBarVisibility="Visible" ScrollViewer.CanContentScroll="False" Focusable="False" Grid.ColumnSpan="2">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid Background="#bd93f9" Margin="64,0,8,0" HorizontalAlignment="Right">
<TextBlock Text="{Binding}" TextWrapping="Wrap" LineStackingStrategy="MaxHeight" Foreground="White" HorizontalAlignment="Right" VerticalAlignment="Stretch" Margin="16,8,32,0" LineHeight="Auto" TextTrimming="None" TextAlignment="Right" Width="Auto" Padding="0" UseLayoutRounding="True">
</TextBlock>
<Button HorizontalAlignment="Right" VerticalAlignment="Center" Width="32" Height="32" Background="{x:Null}" BorderBrush="{x:Null}" Foreground="White" Margin="0">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border
x:Name="border"
Background="{x:Null}"
BorderBrush="{x:Null}"
BorderThickness="0"
CornerRadius="90"
TextBlock.Foreground="White">
<Grid>
<Image
x:Name="buttonImage"
Source="C:\Users\janke\source\repos\Unichat\Unichat\bin\Debug\pictures\icons\reply-line.png" Width="16" Height="16"
/>
<ContentPresenter
Margin="{TemplateBinding Padding}"
HorizontalAlignment="Center"
VerticalAlignment="Center" />
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter TargetName="border" Property="Background" Value="{x:Null}" />
<Setter TargetName="border" Property="BorderBrush" Value="{x:Null}" />
<Setter TargetName="buttonImage" Property="Source" Value="C:\Users\janke\source\repos\Unichat\Unichat\bin\Debug\pictures\icons\reply-fill.png" />
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter TargetName="border" Property="Background" Value="{x:Null}" />
<Setter TargetName="border" Property="BorderBrush" Value="{x:Null}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Button.Style>
</Button>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I want to control the "HorizontalAlignment" of my grid property with a binding so the message either gets aligned right or left, depending on if the message is sent or recieved. I didn't find a way to do that on the internet, even though I know its possible. I just don't understand bindings just yet.
My C# code looks like this:
list_chat.Items.Add(textRange.Text);
Thanks in advance!

The HorizontalAlignment property takes a type of System.Windows.HorizontalAlignment. You want to bind to a property of that type.
public HorizontalAlignment HorizontalAlignmentValue
{
get
{
if (--whatever--)
return HorizontalAlignment.Left;
else if (--whatever--)
return HorizontalAlignment.Right;
}
}
Then you would just set up the binding like usual. If you will need to update this value then be sure to implement INotifyPropertyChanged.
For the binding (in it simplest form):
<Grid HorizontalAlignment="{Binding HorizontalAlignmentValue}" />
Alt:
If you don't want the 'HorizontalAlignmentValue' property to handle its own logic, then you could set up the property with INotifyPropertyChanged and set it elsewhere presumably where the value can be determined, then control updating the UI on change.

Why isnt my button changing colors on MouseOver?

So this is my XAML and for some reason it's not changing colors on mouseover, I added the triggers for it and I thought that would do it, when I hover over the button its not doing anything at all, why is that?
<Button Click="ButtonBase_OnClick" Margin="10,0,0,0" Style="{DynamicResource RoundedButtonStyle}" Width="100" Height="30" HorizontalAlignment="Left">
<Grid>
<Image IsHitTestVisible="False" Height="15" Width="15" VerticalAlignment="Center" HorizontalAlignment="Left" Source="Resources/addButton.png" />
<TextBlock IsHitTestVisible="False" Margin="20,0,0,1" VerticalAlignment="Center" Foreground="#9e9e9e">Add Product</TextBlock>
</Grid>
</Button>
<Window.Resources>
<Style x:Key="RoundedButtonStyle" TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border CornerRadius="5" Background="#2d2d30" BorderThickness="1" Padding="2">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Red"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>

Its not changing because you modified the control template of Button to:
<Border CornerRadius="5" Background="#2d2d30" BorderThickness="1" Padding="2"
Note the hard-coded background color. No matter what you do to the button's Background property it won't take effect since its not used. If you want to use that property in your template you need a TemplateBinding:
Background="{TemplateBinding Background}"
Then in the style set the default to your original value.
<Setter Property="Background" Value="#2d2d30"/>

Button with round edge grid and set disable button color to green

I want to have a button with round edge grid and set disable button color to gray, green otherwise. Attached snippet of code. I don't know how to change the default. If I disable my button, I get the output as the image on the left, however, I want it to look like the image on the right!
<Button x:Name="button" Height="30" Width="100" Margin="825,0,0,0" Background="Transparent"
BorderThickness="0" BorderBrush="Transparent">
<Button.Content>
<Border CornerRadius="12.5" Height="25" Width="95" Margin="0" BorderBrush="Gray"
BorderThickness="4,4,4,4" Background="Gray">
<TextBlock Text="Back" HorizontalAlignment="Center" VerticalAlignment="Top"
Margin="12,0,13,0" Foreground="White"/>
</Border>
</Button.Content>
</Button>

Content is only one part of Button. The rest is determined by Template.
If multiple buttons should have custom apperance, the Template should be set in buttons Style. For one button it can be done inplace:
<Button x:Name="button" Content="Back" Height="30" Width="100" Margin="825,0,0,0" Background="Transparent"
BorderThickness="0" BorderBrush="Transparent">
<Button.Template>
<ControlTemplate TargetType="Button">
<Border CornerRadius="12.5" Height="25" Width="95" Margin="0" BorderBrush="Gray"
BorderThickness="4,4,4,4" Background="Gray">
<TextBlock Text="{TemplateBinding Content}"
HorizontalAlignment="Center" VerticalAlignment="Top"
Margin="12,0,13,0" Foreground="White"/>
</Border>
</ControlTemplate>
</Button.Template>
</Button>
if you are going to reuse the template, declare it as Resource
<Window.Resources>
<ControlTemplate TargetType="Button" x:Key="RoundBtn">
<Border Name="roundBorder" CornerRadius="12.5" Height="25" Width="95" Margin="0" BorderBrush="Gray"
BorderThickness="4,4,4,4" Background="Gray">
<TextBlock Text="{TemplateBinding Content}"
HorizontalAlignment="Center" VerticalAlignment="Top"
Margin="12,0,13,0" Foreground="White"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter TargetName="roundBorder" Property="Background" Value="Green"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Window.Resources>
and set button Template using resource:
<Button x:Name="button" Content="Back" Height="30" Width="100"
Template="{StaticResource RoundBtn}"
Margin="825,0,0,0" Background="Transparent"
BorderThickness="0" BorderBrush="Transparent"/>

This should work for you. I've used an outer grid with a blue background so that I could be sure it was all working, but just remove that and move the style to whichever resources you need to. Explanation as comments within the xaml:
<Grid Background="Blue">
<Grid.Resources>
<!-- Override the default button style, otherwise you get a grey
rectangle behind the ellipse when disabled -->
<Style TargetType="Button" x:Key="MyButtonStyle">
<Setter Property="OverridesDefaultStyle" Value="True" />
<Setter Property="Background" Value="Transparent" />
<Setter Property="Foreground" Value="Transparent" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Grid Background="{TemplateBinding Background}">
<ContentPresenter x:Name="MyContentPresenter"
Content="{TemplateBinding Content}"
HorizontalAlignment="Center"
VerticalAlignment="Center" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Grid.Resources>
<Button x:Name="button" Height="30" Width="100"
BorderThickness="0" BorderBrush="Transparent" IsEnabled="false"
Style="{StaticResource MyButtonStyle}">
<Button.Content>
<Border CornerRadius="12.5" Height="25" Width="95">
<Border.Style>
<Style TargetType="Border">
<!-- Button is gray by default, i.e. when enabled -->
<Setter Property="Background" Value="Gray"/>
<Style.Triggers>
<!-- If the button becomes disabled then it becomes green -->
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Background" Value="Green" />
</Trigger>
</Style.Triggers>
</Style>
</Border.Style>
<TextBlock Text="Back" HorizontalAlignment="Center" VerticalAlignment="Center"
Foreground="White"/>
</Border>
</Button.Content>
</Button>
</Grid>

Making a WPF combobox with rounded corners

In my application, I need to make the combobox that I am using have rounded corners. I started with the XAML posted in the answer to this question and have made some modifications. I decided I didn't like the way that one looked as much, so I tried to style it and make it look a bit more like the default combobox. Now my combobox looks like this: ,
and when dropped down:
The issue is that when the user places their mouse over the combobox, it looks like this: . If I use Snoop, I can see this info:
It says
that the value of that border background is being set to "#FFBEE6FD", which is the color that shows when the mouse is over the combobox. The value source is "ParentTemplateTrigger". My issue is that I don't know where this border is coming from or why it's getting that value. I have tried to add template triggers with setters to set the background to white, but I don't know where to set the value for this mysterious border.
Here is the XAML for my ComboBox:
<ComboBox x:Name="ScanSizesComboBox"
Style="{StaticResource roundedCornersComboBox}"
Grid.ZIndex="4"
ItemsSource="{Binding ScanSizes}"
SelectedItem="{Binding SelectedScanSize, Mode=TwoWay}"
ToolTip="{Binding (Validation.Errors)[0].ErrorContent}"
Margin="0,10,89,0"
HorizontalAlignment="Right"
Width="61"
Height="26"
VerticalAlignment="Top"
Grid.Row="4">
</ComboBox>
And here is the style:
<Style x:Key="ComboBoxTextBoxStyle" TargetType="{x:Type TextBox}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<Grid>
<Border Name="ComboBoxTextBoxStyleBorder" CornerRadius="2"
BorderThickness="0,1,0,1"
Margin="0,0,1,1"
Background="{TemplateBinding Background}">
<Border.Style>
<Style TargetType="Border">
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Background" Value="White"/>
</Trigger>
</Style.Triggers>
</Style>
</Border.Style>
<ScrollViewer x:Name="PART_ContentHost"/>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
<Setter Property="IsReadOnly" Value="True"/>
</Style>
<!--Rounded corners combo box-->
<Style TargetType="{x:Type ComboBox}" x:Key="roundedCornersComboBox">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ComboBox}">
<Border Name="roundedCornerComboBoxBorder" BorderBrush="#CCCCCC" BorderThickness="1" CornerRadius="3" ClipToBounds="True" Background="White">
<Border.Style>
<Style TargetType="Border">
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Background" Value="White"/>
</Trigger>
</Style.Triggers>
</Style>
</Border.Style>
<Canvas>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBox Name="PART_EditableTextBox"
Panel.ZIndex="0"
Style="{StaticResource ComboBoxTextBoxStyle}"
Padding="0,0,0,0"
IsHitTestVisible="False"
Height="{TemplateBinding Height}">
</TextBox>
<ToggleButton Grid.Column="1" Margin="0, 0, 0, 0"
Panel.ZIndex="1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
BorderBrush="Transparent"
Background="Transparent"
Height="{TemplateBinding Height}"
Width="60"
IsChecked="{Binding Path=IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
HorizontalContentAlignment="Right"
ClickMode="Press">
<ToggleButton.Style>
<Style TargetType="ToggleButton">
<Style.Triggers>
<Trigger Property="IsMouseOver"
Value="true">
<Setter Property="Background"
Value="White" />
</Trigger>
</Style.Triggers>
</Style>
</ToggleButton.Style>
<Path Grid.Column="1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Data="M 0 0 L 4 4 L 8 0 Z"
Fill="DodgerBlue" />
</ToggleButton>
<ContentPresenter Name="ContentSite"
Cursor="Arrow"
Content="{TemplateBinding SelectionBoxItem}"
ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="3,0,0,0">
</ContentPresenter>
<Popup Name="Popup"
Placement="Bottom"
IsOpen="{TemplateBinding IsDropDownOpen}"
AllowsTransparency="True"
Focusable="False"
PopupAnimation="Slide">
<Grid Name="DropDown"
SnapsToDevicePixels="True"
MinWidth="{TemplateBinding ActualWidth}"
MaxHeight="{TemplateBinding MaxDropDownHeight}">
<Border
x:Name="DropDownBorder"
BorderThickness="1"
CornerRadius="5"
Background="White"
BorderBrush="Black"/>
<ScrollViewer Margin="4,6,4,6" SnapsToDevicePixels="True">
<StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" />
</ScrollViewer>
</Grid>
</Popup>
</Grid>
</Canvas>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Ultimately, I would like for the user to be able to place his/her mouse over the combobox, and have it just look the same as it does when it is not highlighted. Any help is appreciated. Thanks.

Continuing from our comments conversation (which generally SO tries to avoid so much noise) this may get on you track.
So if I grab just all the template stuff to a bare bones basic default ComboBox and ComboBoxItem from a fresh WPF app, this is the output. Granted you won't need all of it, but it should ensure to an extent all expected functionality and DOM parts are here for reference so you have all the stuff like Triggers, Template Binding pieces etc, all available.
Notice the various Border and Rectangle elements in the various parts that would need to be altered in order to achieve the rounding of everything. I can't however provide any insight into how it would effect anything with MahApps as my experience with that is pretty limited since I've always just made my own stuff to accomplish what it essentially does.
Hope it helps. It's too long for SO's submission requirements though so here's the PasteBin link.

<Style x:Key="ComboBoxTextBoxStyle" TargetType="{x:Type TextBox}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<Grid>
<Border CornerRadius="5,0,0,5"
BorderThickness="1"
Background="{TemplateBinding Background}"
BorderBrush="Black">
<ScrollViewer x:Name="PART_ContentHost"/>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style TargetType="{x:Type ComboBox}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ComboBox}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition MaxWidth="18"/>
</Grid.ColumnDefinitions>
<TextBox Name="PART_EditableTextBox"
Style="{StaticResource ComboBoxTextBoxStyle}"
Padding="5,0,0,0"
Height="{TemplateBinding Height}"/>
<ToggleButton Grid.Column="1" Margin="0"
Height="{TemplateBinding Height}"
Style="{StaticResource ComboBoxButtonStyle}"
Focusable="False"
IsChecked="{Binding Path=IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
ClickMode="Press">
<Path Grid.Column="1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Data="M 0 0 L 4 4 L 8 0 Z"
Fill="DodgerBlue" />
</ToggleButton>
<ContentPresenter Name="ContentSite"
Content="{TemplateBinding SelectionBoxItem}"
ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
VerticalAlignment="Center"
HorizontalAlignment="Left"
Margin="5,0,0,0"/>
<Popup Name="Popup"
Placement="Bottom"
IsOpen="{TemplateBinding IsDropDownOpen}"
AllowsTransparency="True"
Focusable="False"
PopupAnimation="Slide">
<Grid Name="DropDown"
SnapsToDevicePixels="True"
MinWidth="{TemplateBinding ActualWidth}"
MaxHeight="{TemplateBinding MaxDropDownHeight}">
<Border
x:Name="DropDownBorder"
BorderThickness="1"
CornerRadius="5"
Background="Azure"
BorderBrush="Black"/>
<ScrollViewer Margin="4,6,4,6" SnapsToDevicePixels="True">
<StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" />
</ScrollViewer>
</Grid>
</Popup>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

How can I stretch a Border inside a Button?

I am writing a form for a WPF app, and I'd like to use the visual states that Button offers. So my XAML is like this right now:
<Button
Grid.Column="0"
Name="GenderMaleButton"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
BorderThickness="0"
Padding="0">
<Border
Background="White"
BorderThickness="2"
CornerRadius="5"
Padding="5"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch">
<TextBlock/>
</Border>
</Button>
But my Border is not filling my Button. How can I make the Border fill the Button? Or how can I use the visual states of the Button to affect the Border in another way than wrapping the Border inside the Button?
Or can I apply visual states to my Border? If so, how?
EDIT: the result I want is like this:
So a selected state (white border, blue bg), and a default state (blue border, white bg).

From a hard guess , I think you need to fill the border inside the button.Try the code below.Use ControlTemplate
<Button Grid.Column="0"
Name="GenderMaleButton"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
BorderThickness="0"
Padding="0">
<Button.Template>
<ControlTemplate>
<Border Background="#6A6B9A"
BorderThickness="2"
CornerRadius="5"
Padding="5"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch">
<TextBlock TextAlignment="Center" VerticalAlignment="Center" HorizontalAlignment="Center" FontWeight="Bold" Foreground="White" Text="Male"></TextBlock>
</Border>
</ControlTemplate>
</Button.Template>
</Button>

You should have set HorizontalContentAlignment and VerticalContentAlignment to Stretch.
<Button
Grid.Column="0"
Name="GenderMaleButton"
HorizontalContentAlignment="Stretch"
VerticalContentAlignment="Stretch"
BorderThickness="0"
Padding="0">
<Border
Background="White"
BorderThickness="2"
CornerRadius="5"
Padding="5"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch">
<TextBlock/>
</Border>
</Button>

Try this:
<StackPanel Height="40" Orientation="Horizontal">
<StackPanel.Resources>
<Style x:Key="GenderButtonStyle" TargetType="{x:Type Button}">
<Setter Property="MinWidth" Value="100" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border x:Name="InternalBorder"
CornerRadius="5"
Padding="5">
<TextBlock x:Name="InternalText"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Text="{TemplateBinding Content}" />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="Tag" Value="Male">
<Setter TargetName="InternalBorder" Property="Background" Value="RoyalBlue" />
<Setter TargetName="InternalText" Property="Foreground" Value="White" />
</Trigger>
<Trigger Property="Tag" Value="Female">
<Setter TargetName="InternalBorder" Property="Background" Value="White" />
<Setter TargetName="InternalBorder" Property="BorderBrush" Value="RoyalBlue" />
<Setter TargetName="InternalBorder" Property="BorderThickness" Value="1,1,1,1" />
<Setter TargetName="InternalText" Property="Foreground" Value="RoyalBlue" />
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<!-- Whatever you want -->
</Trigger>
<Trigger Property="IsPressed" Value="True">
<!-- Whatever you want -->
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</StackPanel.Resources>
<Button x:Name="MaleButton"
Content="Male"
Style="{StaticResource GenderButtonStyle}"
Tag="Male" />
<Button x:Name="FemaleButton"
Margin="5,0,0,0"
Content="Female"
Style="{StaticResource GenderButtonStyle}"
Tag="Female" />
</StackPanel>
To explain what I've done; I placed two buttons inside a horizontal <StackPanel/> and in its resources subtag I've made a Button Style that can then be assigned to any button you want.
Inside that style I've cracked open the Template and built my own small one that does what you described.
Generally, if a control isn't looking quite the way you want as-is, the best thing to do is open up the template it's made of and make your own.
Like this, you can now define what it should look like when you mouse-over or focus it or press it.