WPF ControlTemplate TargetType match - wpf

Question

I have a component that is derived from a ComboBox. In it, I created a dependency property "myDependencyProp" as the following code. However, in XAML, when I refer to this property, VS says the type is not available in ComboBox and don't run the application. When I set the ControlTemplate TargetType to my:myComboBox, it works correctly, however, VS displays a warning: "myComboBox ControlTemplate TargetType does not match templated type ComboBox". The application runs correctly, but I don't like this warning. How can I fix it? Thanks! (Obs: my: is just a ficticious alias to myNameSpaces).
C#:
namespace myNameSpace
{
public partial class myComboBox : ComboBox
{
public static readonly DependencyProperty myDependencyPropProperty =
DependencyProperty.Register("myDependencyProp", typeof(bool),
typeof(myComboBox), new UIPropertyMetadata(false));
public myComboBox()
{
InitializeComponent();
}
public bool IsFirstItemTip
{
get { return (bool)GetValue(myDependencyPropProperty); }
set { SetValue(myDependencyPropProperty, value); }
}
}
}
XAML:
<ComboBox.Resources>
<Style x:Key="myComboBox" TargetType="{x:Type ComboBox}">
<Setter Property="SnapsToDevicePixels" Value="true"/>
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type my:myComboBox}">
<Grid>
<ToggleButton
...
</ToggleButton>
<ContentPresenter
...
</ContentPresenter>
<Popup
...
</Popup>
</Grid>
<ControlTemplate.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="SelectedIndex" Value="0"/>
<Condition Property="myDependencyProp" Value="True"/>
</MultiTrigger.Conditions>
<MultiTrigger.Setters>
<Setter ... />
</MultiTrigger.Setters>
</MultiTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ComboBox.Resources>

Answer 1

change this line
<Style x:Key="myComboBox" TargetType="{x:Type ComboBox}"> to <Style x:Key="myComboBox" TargetType="{x:Type my:myComboBox}"> to get rid of the warning. The warning is telling you that your style will implicitly get applied to all ComboBoxes but the control template is intended for those types which are derived from myComboBox

Answer 2

Thanks for the answers, but I solved the problem by doing the following:
First, I returned all TargetTypes to {x: Type ComboBox}, then all warnings are gone.
After, instead of using the MultiTrigger as previously presented, I used MultiDataTrigger, as the code below:
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=SelectedIndex, RelativeSource={RelativeSource Self}}" Value="0"/>
<Condition Binding="{Binding Path=myDependencyProp, RelativeSource={RelativeSource Self}}" Value="True"/>
</MultiDataTrigger.Conditions>
<MultiDataTrigger.Setters>
<Setter .../>
</MultiDataTrigger.Setters>
</MultiDataTrigger>
That is it!