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How to change background of the template item, on selecting DataGridCell

I need to change the background color of a Textbox that is inside DataGridTemplateColumn cell based on whether or not if the data cell is selected.
Currently what I managed to do is, changing the background color of the template cell, which became useless because of error management.
Thus, I want to change the background of the Textbox, and revert it back on selection changed.
<DataGrid.Resources>
<Style TargetType="{x:Type DataGridRow}">
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="Background" Value="DarkBlue"/>
<Setter Property="Foreground" Value="Black"/>
</Trigger>
</Style.Triggers>
</Style>
</DataGrid.Resources>
<DataGrid.Columns>
<DataGridTemplateColumn IsReadOnly="True" MinWidth="150" Width="*">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBox Text="{Binding Path=TwoDLineName, Mode=TwoWay,UpdateSourceTrigger=LostFocus, ValidatesOnDataErrors=True, NotifyOnValidationError=True}"
HorizontalAlignment="Stretch" Style="{StaticResource TextBoxValidated}"/>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

You could use a Style with a DataTrigger that binds to the IsSelected property of the parent row:
<DataGridTemplateColumn IsReadOnly="True" MinWidth="150" Width="*">
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<TextBox Text="{Binding Path=TwoDLineName, Mode=TwoWay,UpdateSourceTrigger=LostFocus, ValidatesOnDataErrors=True, NotifyOnValidationError=True}">
<TextBox.Style>
<Style TargetType="TextBox" BasedOn="{StaticResource TextBoxValidated}">
<Style.Triggers>
<DataTrigger Binding="{Binding IsSelected,
RelativeSource={RelativeSource AncestorType=DataGridRow}}"
Value="True">
<Setter Property="Background" Value="Red" />
</DataTrigger>
</Style.Triggers>
</Style>
</TextBox.Style>
</TextBox>
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>

DataTrigger with Property = ItemControl.ItemTemplate

I Am having some trouble getting this binding to work. I have several objects within SettingCollection that all have an enum property. I want to generate a control based on what the value of this is. But when I check this value with a data trigger it does not work.
Can anyone provide some insight into how i can accomplish this?
<Window.Resources>
<DataTemplate x:Key="CheckboxNode">
<CheckBox IsChecked="{Binding Status}" Margin="0,5,0,0">
<ContentPresenter Content="{Binding DisplayName}"/>
</CheckBox>
</DataTemplate>
<DataTemplate x:Key="TextboxNode">
<TextBox Text="Badgers"></TextBox>
</DataTemplate>
</Window.Resources>
<ItemsControl ItemsSource="{Binding SettingCollection}">
<ItemsControl.Style>
<Style TargetType="ItemsControl">
<Style.Triggers>
<DataTrigger Binding="{Binding Type}" Value="checkbox">
<Setter Property="ItemsControl.ItemTemplate" Value="{StaticResource CheckboxNode}" />
</DataTrigger>
<DataTrigger Binding="{Binding Type}" Value="textbox">
<Setter Property="ItemsControl.ItemTemplate" Value="{StaticResource TextboxNode}" />
</DataTrigger>
</Style.Triggers>
</Style>
</ItemsControl.Style>
</ItemsControl>

If Type property is in SettingNode class, and SettingCollection is a collection of SettingNode objects, then your binding in the Datatriggers is incorrect. DataTriggers will look for Type property in ItemsControl DataContext (class with SettingCollection). Try to use DataTemplateSelector https://msdn.microsoft.com/en-us/library/system.windows.controls.datatemplateselector(v=vs.110).aspx

DataTemplate Based on Value of Bound Property in ItemsSource of TabControl

Ok. So I have a TabControl object in my xaml that has an ItemsSource value of ItemsSource={Binding OpenTabs} where OpenTabs is an ObservableCollection of type ClosableTab (public ObservableCollection<ClosableTab> OpenTabs { get; set; }) which extends TabItem. I found ClosableTab from here and then have adapted it's view for my own needs.
Primarily I have added a property (and sorry for the confusion in names here) isProperty. This is for a real estate program. Then in my xaml I have the following lines:
<DataTemplate x:Key="PropertyTemplate">
<Grid>
<TextBlock Text="{Binding address}"/>
</Grid>
</DataTemplate>
<DataTemplate x:Key="TennantTemplate">
<Grid>
<TextBlock Text="{Binding name}"/>
</Grid>
</DataTemplate>
//... That's in <Windows.Resources>
<TabControl ItemsSource="{Binding OpenTabs}" Grid.Column="1" x:Name="Tabs">
<TabControl.Resources>
<DataTemplate x:Key="DefaultTab">
<ContentControl>
<ContentControl.Triggers>
<DataTrigger Binding="{Binding isProperty}" Value="True">
<Setter Property="ContentTemplate" Value="{StaticResource PropertyTemplate}" />
</DataTrigger>
<DataTrigger Binding="{Binding isProperty}" Value="False">
<Setter Property="ContentTemplate" Value="{StaticResource TennantTemplate}" />
</DataTrigger>
</ContentControl.Triggers>
</ContentControl>
</DataTemplate>
</TabControl.Resources>
</TabControl>
I've done some research and found that this is what I need to do if I want to have a certain DataTemplate dependant on the property in ClosableTab called isProperty.
It's not giving me what I want. Can someone please explain to me what I'm doing wrong here? And tell me what I should do? And/or possibly give me an alternative method? I can't think of what I need to change to get the functionality that I need. Thanks in advance.

You need to set DataType on DataTemplate to get it applied automatically to underlying data objects in case you are defining DataTemplate under Resources section.
<DataTemplate DataType="local:ClosableTab">
<ContentControl>
<ContentControl.Triggers>
<DataTrigger Binding="{Binding isProperty}" Value="True">
<Setter Property="ContentTemplate"
Value="{StaticResource PropertyTemplate}" />
</DataTrigger>
<DataTrigger Binding="{Binding isProperty}" Value="False">
<Setter Property="ContentTemplate"
Value="{StaticResource TennantTemplate}" />
</DataTrigger>
</ContentControl.Triggers>
</ContentControl>
</DataTemplate>
Make sure to declare local namespace at root level to the one where ClosableTab is declared.
OR
Instead of adding DataTemplate in resources, set it explicitly as ItemTemplate of TabControl.
<TabControl>
<TabControl.ItemTemplate>
<DataTemplate x:Key="DefaultTab">
.....
</DataTemplate>
</TabControl.ItemTemplate>
</TabControl>
UPDATE
Ideal case would be to have single DataTemplate and apply dataTrigger on TextBlock instead.
<TabControl ItemsSource="{Binding OpenTabs}">
<TabControl.ItemTemplate>
<DataTemplate>
<TextBlock>
<TextBlock.Style>
<Style TargetType="TextBlock">
<Setter Property="Text" Value="{Binding address}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding isProperty}"
Value="False">
<Setter Property="Text" Value="{Binding name}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>
</DataTemplate>
</TabControl.ItemTemplate>
</TabControl>

How can I know if item is selected inside the ItemTemplate?

I have a ListBox that use my custom ItemTemplate. I want to set Visibility property in my TextBlock (inside my template) depending on selected item. I think of doing it using triggers. But how can I know inside my template if current item is selected or not?
<DataTemplate x:Key="myTemplate">
<StackPanel Orientation="Horizontal">
<Image Tag="{Binding priority}" Loaded="SetIconPriority"/>
<Image Tag="{Binding alarm}" Loaded="SetIconAlarm"/>
<!-- I want this TextBlock to be visible only when item is selected -->
<TextBlock Text="{Binding description}"/>
</StackPanel>
</DataTemplate>
edit:
It works, thanks! Code:
<TextBlock Grid.Column="2" Grid.Row="1" Text="{Binding opis}">
<TextBlock.Style>
<Style TargetType="TextBlock">
<Style.Triggers>
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource AncestorType=ListBoxItem}}" Value="False">
<Setter Property="Visibility" Value="Collapsed"/>
</DataTrigger>
</Style.Triggers>
</Style>
</TextBlock.Style>
</TextBlock>

Using a RelativeSource binding with AncestorType being ListBoxItem.
<DataTrigger Binding="{Binding IsSelected,
RelativeSource={RelativeSource AncestorType=ListBoxItem}}"
Value="True">
(May want to reverse the logic and Collapse on False instead, avoids the default value Setter)

WPF: Change background on some combobox items

I'm trying to change the background of certain items in a combobox that meet a condition
<ComboBox ItemsSource="{Binding Path=Model.Names, Mode=OneWay}" SelectedValue="{Binding Path=SelectedCompanyName}" DisplayMemberPath="Alias" />
The thing is that "Alias" is saved in two different places (in company and in order) and if they dont match we want to highlight this.
I want to do something like this:
<Style>...
<DataTrigger Binding="{Binding Path=isMismatch}" Value="True>
<Setter Property="Background" Value="Red" />...
Any help is appreciated.

You need to create custom data template like this:
<ComboBox Width="300" Height="30" ItemsSource="{Binding Path=Model.Names, Mode=OneWay}">
<ComboBox.ItemTemplate>
<DataTemplate>
<Grid x:Name="templateGrid">
<TextBox Text="{Binding Name}" />
</Grid>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding isMismatch}" Value="True">
<Setter TargetName="templateGrid"
Property="Background" Value="Red" />
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>

If you want to highlight the selection based on the values of two properties, I think you could use a MultiValueConverter, together with a MultiBinding.