Develop Reference

How to control Visibility of ComboBox based on radio button is checked

I have a quick WPF question in regards to the visibility of my ComboBox with respects to whether or not a button is checked or not. The goal is that when the user checks the radio button: 'btnCurrent', the ComboBox: cboHistorySequence will be hidden, and when the button 'btnHistory' is checked, it will appear.
VIEW: Here we have the radio button 'btnCurrent' and 'btnHistory', as well as combobox cboHistorySequence.
<RadioButton x:Name="btnCurrent" IsChecked="{Binding IsCurrentSelected, UpdateSourceTrigger=PropertyChanged}" Content="Current" Grid.Column="0" Grid.Row="0"/>
<RadioButton x:Name="btnHistory" IsChecked="{Binding IsHistorySelected, UpdateSourceTrigger=PropertyChanged}" Content="History" Grid.Row="0" Grid.Column="1"/>
<StackPanel Orientation="Horizontal" Grid.Row="3" Grid.Column="0" Grid.ColumnSpan="2" Margin="5,0" IsEnabled="{Binding IsHistorySelected, Converter={StaticResource EnabledConverter} }">
<TextBlock HorizontalAlignment="Left" Width="80">History Seq:</TextBlock>
<ComboBox x:Name="cboHistorySequence" Margin="16,0,0,0" Text="{Binding Path=HistorySequence, UpdateSourceTrigger=PropertyChanged}" Width="80" HorizontalAlignment="Left">
<ComboBoxItem>First</ComboBoxItem>
<ComboBoxItem>Last</ComboBoxItem>
</ComboBox>
</StackPanel>
What I have tried
My initial thought was to use something along the lines of this and bind it over to the view-model, but I have not been successful. What are yall's recommendations?
Visibility="{Binding IsShowComboBox, Converter={StaticResource VisibilityConverter}

Because you want to bind to the property of another element in your application you should use Binding.ElementName Property and Path, something like this:
<ComboBoxItem>Last</ComboBoxItem>
<ComboBox.Style>
<Style TargetType="{x:Type ComboBox}">
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=btnCurrent, Path=IsChecked}" Value="True">
<Setter Property="Visibility" Value="Hidden" />
</DataTrigger>
</Style.Triggers>
</Style>
</ComboBox.Style>

ComboBox with fixed Header

I need to show a default text in my ComboBox, this text must not changed also when the user select an item of the Combobox, actually for do this I've created this structure:
<ComboBox ItemsSource="{Binding AvailableNations}" Width="160" Height="55" Margin="0, 0, 0, 15"
Text="Select Countries" IsEditable="True">
<ComboBox.ItemTemplate>
<DataTemplate>
<CheckBox IsChecked="{Binding IsChecked}" Content="{Binding Item.Name}" />
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
this display as default text Select Countries but if I select an item the default text will disappear and the item selected will be displayed, how can I fix this?

You could use a Combined Template (ref post)
<Window.Resources>
<ResourceDictionary>
<DataTemplate x:Key="NormalItemTemplate" >
<CheckBox IsChecked="{Binding IsChecked}" Content="{Binding Item.Name}" />
</DataTemplate>
<DataTemplate x:Key="SelectionBoxTemplate" >
<TextBlock>Select Countries</TextBlock>
</DataTemplate>
<DataTemplate x:Key="CombinedTemplate">
<ContentPresenter x:Name="Presenter"
Content="{Binding}"
ContentTemplate="{StaticResource NormalItemTemplate}" />
<DataTemplate.Triggers>
<DataTrigger
Binding="{Binding RelativeSource={RelativeSource FindAncestor,ComboBoxItem,1}}"
Value="{x:Null}">
<Setter TargetName="Presenter" Property="ContentTemplate"
Value="{StaticResource SelectionBoxTemplate}" />
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</ResourceDictionary>
</Window.Resources>
<Grid>
<ComboBox ItemsSource="{Binding AvailableNations}"
SelectedItem="{Binding SelectedNation}"
ItemTemplate="{StaticResource CombinedTemplate}"
Width="160" Height="55" Margin="0, 0, 0, 15" >
</ComboBox>
</Grid>
The way it works is described in the original answer. Note that the suggested solution will only work when IsEditable is set to false, I assume that won't be a problem in your case. Second, to get the text displayed at start up I bound SelectedItem (e.g. to the first item in the collection).

From the comments, it sounds like you just want the Select Countries text to display at all times, even when an item is selected.
Personally I would just go the simple route and place a TextBox on top of the ComboBox, and hide the Display Text of the ComboBox by using a Transparent Foreground color.
Here's a quick example demonstrating it :
<Grid>
<ComboBox SelectedIndex="1" Foreground="Transparent">
<ComboBox.Resources>
<Style TargetType="{x:Type ComboBoxItem}">
<!-- Make sure ComboBoxItems don't have transparent text -->
<Setter Property="Foreground" Value="{StaticResource {x:Static SystemColors.ControlTextBrushKey}}" />
</Style>
</ComboBox.Resources>
<ComboBoxItem>Test 1</ComboBoxItem>
<ComboBoxItem>Test 2</ComboBoxItem>
<ComboBoxItem>Test 3</ComboBoxItem>
</ComboBox>
<TextBlock Text="Select Countries" Margin="4,3" IsHitTestVisible="False" />
</Grid>
And the results (note that SelectedIndex = 1)
I'm sure there's other ways too, such as overwriting the way it paints the display text, or changing the control template, but this seemed like the easiest to me.

Conditional Context Menu Triggers

I currently have two buttons. One button is to Showappointments(), the other is ShowTask(). When either is clicked the FontWeight of that button goes to bold. Only one can be bolded at a time. I use that as the indicator to show which is being displayed.
The values are then displaye in a ListBox. I'm trying to have a condition such that when ShowTask fontweight is Bold it'll display the corresponding contextMneu for the Task, and it'll display a different set of contextmenus for Appointments.
<ListBox ItemsSource="{Binding FilteredEventsCollection}"
<Style TargetType="{x:Type ListBox}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=AppointmentBold}" Value="Bold">
<Setter Property="ContextMenu" Value="{StaticResource Menu1}"></Setter>
</DataTrigger>
</Style.Triggers>
</Style>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel cal:Message.Attach="[Event MouseDoubleClick] = [Action Open()]">
<TextBlock Text="{Binding Date, StringFormat=g}" Foreground="Black" FontWeight="Bold" FontFamily="Segoe UI"/>
<TextBlock Text="{Binding Title}" />
<TextBlock Text="{Binding Company}" Foreground="Black"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
User Control Resources
<ContextMenu x:Key="TaskMenu">
<MenuItem>Open This Task</MenuItem>
</ContextMenu>
<ContextMenu x:Key="AppointmentMenu">
<MenuItem>Open This Appointment</MenuItem>
</ContextMenu>
This piece of code crashes right away, I'm wondering if I'm approaching correct and if I can get some guidance

WPF ListBox select word with mouse

Is it possible to select single words with the mouse in a WPF ListBox control? When yes, how can I do that?
All hints are welcome :)

If you define an ItemTemplate for your ListBox, you can use a TextBox to display each item (assuming that your items are plain strings):
<ListBox ItemsSource="{Binding YourCollection}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox Text="{Binding}" IsReadOnly="True" />
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
UPDATE >>>
I just tested it and had to make one change to set the Binding.Mode property to OneWay and it worked just fine. However, I noticed that the TextBox would stop each item from being selected, so added a Style to take care of that and styled the items a little bit too:
<ListBox ItemsSource="{Binding YourCollection}" Name="ListBox" HorizontalContentAlignment="Stretch">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBox Text="{Binding ., Mode=OneWay}" IsReadOnly="True">
<TextBox.Style>
<Style>
<Setter Property="TextBox.BorderThickness" Value="0" />
</Style>
</TextBox.Style>
</TextBox>
</DataTemplate>
</ListBox.ItemTemplate>
<ListBox.ItemContainerStyle>
<Style>
<Style.Triggers>
<Trigger Property="ListBox.IsKeyboardFocusWithin" Value="True">
<Setter Property="ListBoxItem.IsSelected" Value="True" />
</Trigger>
</Style.Triggers>
</Style>
</ListBox.ItemContainerStyle>
</ListBox>

Textblock selected foreground color in datagrid WPF

I have created a datagrid in WPF...
I have defined several custom Columns..
<my:DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding HeadC}" />
<TextBlock Text="{Binding HeadCPercent}" Foreground="#FFF05D1D" />
</StackPanel>
</DataTemplate>
</my:DataGridTemplateColumn.CellTemplate>
The problem is that when a row is slected the seconds textblock color doesnt change and it is hardly visible...
Any solution to this problem ?

Add DataTrigger to the DataTemplate triggers collection that would change foreground based on selected state of the row. Like in the following example:
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding HeadC}" />
<TextBlock x:Name="tbPercent" Text="{Binding HeadCPercent}" Foreground="#FFF05D1D"/>
</StackPanel>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type dg:DataGridRow}}}" Value="True">
<Setter Property="Foreground" TargetName="tbPercent" Value="Blue" />
</DataTrigger>
</DataTemlate.Triggers>
</DataTemplate>
I took this answer as a basis and adjusted it to your question. I could made a typo in the code but you should get the idea :). Hope it helps.