Binding not working for error validation - c#

I have style for validation error of a control .I show the error in tooltip also I want to show it in a Textblock next to control.The binding in tooltip works fine but its doesnt work with textblock.I tried hardcoding some text in textblock it works ,but binding is not working.
<Style TargetType="{x:Type Control}" x:Key="S_ErrorTemplate">
<Setter Property="Validation.ErrorTemplate">
<Setter.Value>
<ControlTemplate>
<DockPanel LastChildFill="True">
<TextBlock DockPanel.Dock="Right" Foreground="Red"
FontSize="12pt"
Text="{Binding Path=(Validation.Errors)[0].ErrorContent,
RelativeSource={RelativeSource TemplatedParent}}" />
<Border BorderBrush="Green" BorderThickness="1" >
<AdornedElementPlaceholder Name="myControl"/>
</Border>
</DockPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="true">
<Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
<Setter Property="Background" Value="Maroon"/>
</Trigger>
</Style.Triggers>
</Style>

Related

WPF override custom template using trigger XAML tag on validation

So I have a style for my TextBox as shown
<Style TargetType="TextBox">
<Setter Property="FontSize" Value="20">
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="TextBox">
<StackPanel>
<!-- ScrollViewer to restore the default textbox template that is gone because of
us now overriding it -->
<Border CornerRadius="2" Padding="2" Background="White" BorderBrush="Black" BorderThickness="1">
<ScrollViewer Margin="0" x:Name="PART_ContentHost" Background="Gray" />
</Border>
<ItemsControl FontSize="10" ItemsSource="{TemplateBinding Validation.Errors}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Foreground="Red" Text="{Binding Path=ErrorContent}"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter Property="Background" Value="Red"/>
<Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</Style.Triggers>
</Style>
When there is an error, I'd like the text box to show a red background, with the error messages appearing underneath it. I've set up a trigger to change the TextBox's background when there's an error, but it seems that since I override the TextBox's normal template so that I can show the error messages, the background of the textbox itself doesn't change (it stays gray). I realize that this is because I used a ScrollViewer to restore the textbox appearance, but now how can I somehow refer to this ScrollViewer from my trigger?
It's more for learning purposes.
You need to better use ControlTemplate.
Possible example:
<Style TargetType="TextBox">
<Setter Property="FontSize" Value="20"/>
<Setter Property="Background" Value="Gray"/>
<Setter Property="BorderBrush" Value="Black"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="TextBox">
<StackPanel>
<!-- ScrollViewer to restore the default textbox template that is gone because of
us now overriding it -->
<Border x:Name="PART_Border" CornerRadius="2"
Padding="{TemplateBinding Padding}"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<ScrollViewer Margin="0" x:Name="PART_ContentHost"/>
</Border>
<ItemsControl FontSize="10" ItemsSource="{TemplateBinding Validation.Errors}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Foreground="Red" Text="{Binding Path=ErrorContent}"/>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
<ControlTemplate.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter TargetName="PART_Border" Property="Background" Value="Red"/>
<Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self},
Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
but now how can I somehow refer to this ScrollViewer from my trigger?
Move the trigger from the Style to the ControlTemplate and use the TargetName property of the Setter to refer to the ScrollViewer or the parent Border element inside the template, e.g.:
<ControlTemplate TargetType="TextBox">
<StackPanel>
<Border ...>
<ScrollViewer Margin="0" x:Name="PART_ContentHost" Background="Gray" />
</Border>
<ItemsControl ... />
</StackPanel>
<ControlTemplate.Triggers>
<Trigger Property="Validation.HasError" Value="True">
<Setter TargetName="PART_ContentHost" Property="Background" Value="Red"/>
...
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>

How to trigger parent element using child?

What I am trying to do is when my mouse got over a button inside a border that border background color must change.
<Border Name="HistoryBorder"
Grid.Column="0"
Height="30"
VerticalAlignment="Top"
Margin="0,0,326.8,0"
Background="#FF323030"
CornerRadius="0,0,15,0"
MouseDown="draging_bar">
<Button HorizontalAlignment="Center"
VerticalAlignment="Center"
Width="75"
Name="HistoryButton"
Height="30"
Margin="0"
FontFamily="/Fonts/#Minecraft"
Foreground="#FFB6B002" >
<Button.Content>
History
</Button.Content>
<Button.Style>
<Style TargetType="Button">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=HistoryButton, Path=IsMouseOver}" Value="True">
<DataTrigger.Setters>
<Setter Property="Background" Value="Green" />
</DataTrigger.Setters>
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
</Border>
As you can see border is parent and button is a child in it. When I try to use targetname it is not working. Is something like that even possible ?
As far as I understand, setting Style for Border to be bind with it's child's IsMouseOver can be one of the ways.
<Border Name="HistoryBorder"
Grid.Column="0"
Height="30"
VerticalAlignment="Top"
Margin="0,0,326.8,0"
CornerRadius="0,0,15,0"
>
<!-- You have to put Background color to Style. Or priority makes it cannot be overrided from the Setter of Style -->
<Border.Style>
<Style TargetType="{x:Type Border}">
<Setter Property="Background" Value="#FF323030"/>
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=HistoryButton, Path=IsMouseOver}" Value="True">
<DataTrigger.Setters>
<Setter Property="Background" Value="Black"/>
</DataTrigger.Setters>
</DataTrigger>
</Style.Triggers>
</Style>
</Border.Style>
...

WPF Rounded border button responsive to click color change

I have a button on my WPF application (MVVM Pattern) which is responsive to a click event. Basically if you click on this button its background becomes LightGreen (the default color is LightGray). I already achieved the desired behavior using the following code:
<Button Grid.Column="2" Grid.Row="6" Grid.ColumnSpan="3" Grid.RowSpan="2" Content="{Binding FirstSchedule.Message}" Command="{Binding FirstScheduleButtonClick}">
<Button.Style>
<Style TargetType="Button">
<Setter Property="Background" Value="LightGray"></Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding FirstScheduleButtonSelected}" Value="True">
<Setter Property="Background" Value="LightGreen"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
In which FirstScheduleButtonSelected is a ViewModel property defined by:
private bool _firstScheduleButtonSelected;
public bool FirstScheduleButtonSelected
{
get { return _firstScheduleButtonSelected; }
set { _firstScheduleButtonSelected = value; NotifyPropertyChanged("FirstScheduleButtonSelected"); NotifyPropertyChanged("Background"); }
}
Now I need to make this button's borders rounded. I already tried this solution How to create/make rounded corner buttons in WPF?, and I ended up with:
<Button Grid.Column="2" Grid.Row="6" Grid.ColumnSpan="3" Grid.RowSpan="2" Content="{Binding FirstSchedule.Message}" Command="{Binding FirstScheduleButtonClick}">
<Button.Style>
<Style TargetType="Button">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border CornerRadius="15" Background="LightGray" BorderThickness="1" Padding="2">
<ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Setter Property="Background" Value="LightGray"></Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding FirstScheduleButtonSelected}" Value="True">
<Setter Property="Background" Value="LightGreen"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
Now my borders are, in fact, rounded but when I click the button it does not becomes green.
Q: How can I modify this button in order to make its borders rounded and keep my already functioning behavior of changing its color on click?
Here's what I'd do:
<Window.Resources>
<!-- ... -->
<Style x:Key="GreenToggleButtonStyle" TargetType="ToggleButton">
<Setter Property="Background" Value="LightGray" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Border
CornerRadius="15"
Background="{TemplateBinding Background}"
BorderThickness="1"
Padding="2"
>
<ContentPresenter
HorizontalAlignment="Center"
VerticalAlignment="Center"
/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter
Property="Background"
Value="LightGreen"
/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<!-- ... -->
</Window.Resources>
...
<ToggleButton
Grid.Column="2"
Grid.Row="6"
Grid.ColumnSpan="3"
Grid.RowSpan="2"
Content="{Binding FirstSchedule.Message}"
IsChecked="{Binding FirstScheduleButtonSelected}"
Style="{StaticResource GreenToggleButtonStyle}"
/>

MouseOver effect for button in DataTemplate

I use a DataTemplate to show some buttons with a customized view (with an image, text, etc). Here is a simplified example:
<DataTemplate DataType="{x:Type viewModel:ActionItem}">
<Button Background="SlateGray" Command="{Binding Command}">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="Background" Value="Green"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="DarkGoldenrod"/>
</Trigger>
</Style.Triggers>
</Style>
</Button.Style>
<TextBlock Text="{Binding Name}" />
</Button>
</DataTemplate>
Why is the mouse over effect not working at all?
Because Background="SlateGray" overrides anything you can trigger in a Style. Remove that bit and it should work.
Please set the trigger at at the template level like
<DataTemplate DataType="{x:Type viewModel:ActionItem}">
<Button Background="SlateGray" Command="{Binding Command}">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Setter Property="Background" Value="Green"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Border Background="{TemplateBinding Background}">
<ContentPresenter />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="DarkGoldenrod"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Button.Style>
<TextBlock Text="{Binding Name}" />
</Button>
</DataTemplate>

Changing the background of a button in a DataGrid if the row is selected - WPF

I have a datagrid which contains a template column which holds a few buttons.
I need the color of these buttons to change from black to white when the row is selected.
Although I am not sure how can I reach "DataGridRow.IsSelected" from the buttons setters.
Here is what I tried and didn't work:
<DataGridTemplateColumn>
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Button CommandParameter="{Binding RelativeSource={RelativeSource Mode=Self}, Path=DataContext}"
Command="{Binding ViewModel.OnRemoveDirectoryClick, ElementName=Root}">
<Button.Style>
<Style>
<Setter Property="Button.Background">
<Setter.Value>
<ImageBrush ImageSource="../../Images/menu_delete.png"/>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="DataGridRow.IsSelected" Value="True">
<Setter Property="Button.Background">
<Setter.Value>
<ImageBrush ImageSource="../../Images/menu_delete_white.png"/>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>
</StackPanel>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
Thanks ahead,
Yotam
Eventually I found that I needed to use DatatTrigger with a relative source to DataGridRow
<Button.Style>
<Style>
<Setter Property="Button.Background">
<Setter.Value>
<ImageBrush ImageSource="../../Images/menu_delete.png"/>
</Setter.Value>
</Setter>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=IsSelected, RelativeSource={RelativeSource AncestorType={x:Type DataGridRow}}}" Value="True">
<Setter Property="Button.Background">
<Setter.Value>
<ImageBrush ImageSource="../../Images/menu_delete_white.png"/>
</Setter.Value>
</Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
An additional and perhaps more elegant way I found to tackle this problem was using a template which contains rectangle with white filling which takes the button's background as the opacity mask.
<ControlTemplate x:Key="DataGridButtonTemplate" TargetType="{x:Type Button}">
<Grid Style="{x:Null}">
<Rectangle x:Name="Mask" Width="{TemplateBinding Width}" Height="{TemplateBinding Height}" Opacity="{StaticResource NormalOpacity}" Style="{x:Null}"
OpacityMask="{TemplateBinding Background}" Fill="White" Visibility="{Binding Path=IsSelected, RelativeSource={RelativeSource AncestorType={x:Type DataGridRow}}, Converter={StaticResource BoolToVisibilityConverter}}"/>
</Grid>
</ControlTemplate>
Try putting this style as Resource
<Style TargetType="{x:Type DataGridCell}">
<Style.Triggers>
<Trigger Property="DataGridCell.IsSelected"
Value="True">
<Setter Property="Foreground" TargetName="YourButtonName"
Value="YourColor" />
</Trigger>
</Style.Triggers>
</Style>

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