objects added to an IDictionary must have a Key attribute [modified]

[Lutoslaw]

Hello again! It is another time I encounter this error: "objects added to an IDictionary must have a Key attribute or some other type of key associated with them.". I searched google to find out what is going on, but in every case the reason was that somebdy didn't set either Key or TargetType. I my case, I set the TargetType, but it doesn't work. In my previous post the problem was that I was using a UserControl. Now I try to set a template of a ToggleButton which is not a UserControl. WTH is going on? :confused:

(...)

The error started to appear since I changed something. I had tried to revert my recent changes but I couln't work out what is wrong :doh:
EDIT: I've tried to set x:Key and reference Template={StRes key} and got exception:

{"'Set property 'System.Windows.DataTrigger.Binding' threw an exception.' Line number '59' and line position '18'."}

Inner:

{"Unable to cast object of type 'System.Windows.TemplateBindingExpression' to type 'System.Windows.Data.BindingBase'."}

Inner:null
Edit2: IsChecked IS a dep property
Any ideas?

Greetings - Jacek

modified on Monday, May 16, 2011 5:46 AM

[Lutoslaw]

This works:

    <Style TargetType="ToggleButton">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="ToggleButton">
                    <Image MouseDown="Image\_MouseDown" Source="{StaticResource CheckedImage}" Height="16" />
                </ControlTemplate>
            </Setter.Value>                
        </Setter>
        <Style.Triggers>
            <DataTrigger Binding="{Binding Path=IsChecked, RelativeSource={RelativeSource Mode=TemplatedParent}}" Value="True">
                <Setter Property="Opacity" Value="1" />
            </DataTrigger>
            <DataTrigger Binding="{Binding Path=IsMoueseOver, RelativeSource={RelativeSource Mode=TemplatedParent}}" Value="True">
                <Setter Property="Opacity" Value="0.7" />
            </DataTrigger>
        </Style.Triggers>
    </Style>

private void Image_MouseDown(object sender, MouseButtonEventArgs e)
{
var img = (Image)sender;
var toggle = (ToggleButton)img.TemplatedParent;
toggle.IsChecked = true;
}

BUT the triggers doesn't work. I mouseover and opacity doesn't change. I click opacity doesn't change :confused: Oh WPF makes me head not working. I is confusing.

Greetings - Jacek

[Venkatesh Mookkan]

When you write ControlTemplate you can use normal Triggers and EventTriggers. DataTriggers are meant to use along with DataTemplate. And also Key is a must for <ControlTemplete> whereas Style doesn't require one.

Venkatesh Mookkan (My Recent Article: WPF Custom Control - FilterControl for ListBox/ListView)

[markovl]

Yes, that's true. This worked for me:

<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Opacity" Value="1" />
</Trigger>
</ControlTemplate.Triggers>

You may need to supply TargetName for the Setter.

[Venkatesh Mookkan]

TargetName is not required in his case. :)

Venkatesh Mookkan (My Recent Article: WPF Custom Control - FilterControl for ListBox/ListView)

[Lutoslaw]

Whoa! Thanks. :thumbsup:

Greetings - Jacek