Why cant I code like this
<Border Width="130" Height="70">
<Border.Triggers>
<DataTrigger Binding="{Binding Path=CurrentStatus}" Value="0">
<Setter Property="Style" Value="{StaticResource ResourceKey=ListBoxItemBorder}"/>
</DataTrigger>
<DataTrigger Binding="{Binding Path=CurrentStatus}" Value="200">
<Setter Property="Style" Value="{StaticResource ResourceKey=ListBoxItemBorderInactive}"/>
</DataTrigger>
</Border.Triggers>
</Border>
I get this error
Failed object initialization (ISupportInitialize.En开发者_高级运维dInit).
Triggers collection members must be of type EventTrigger.
Error at object '4_T' in markup file
What am I doing wrong plz help.
Abe is correct and explains the limitations well. One thing you might want to consider is:
Instead of having two border styles, and trying to pick between them based on a trigger...
Use a single style on your border, this style's setters represent your 'normal' look. This style also contains your DataTrigger, and your DataTrigger has a collection of setters which essentially represents your second style (which have higher priority than the standard setters when this trigger evaluates to true!
Edit:
Something like this -
<Style TargetType="Border" x:Key="BorderStyle">
<!-- These setters are the same as your normal style when none of your triggers are true -->
<Setter Property="BorderBrush" Value="Black" />
<Style.Triggers>
<DataTrigger Binding="{Binding Path=CurrentStatus}" Value="0">
<!-- These setters are the same as your ListBoxItemBorder style -->
<Setter Property="BorderBrush" Value="Green" />
</DataTrigger>
<DataTrigger Binding="{Binding Path=CurrentStatus}" Value="200">
<!-- These setters are the same as your ListBoxItemBorderInactive style -->
<Setter Property="BorderBrush" Value="Gray" />
</DataTrigger>
</Style.Triggers>
</Style>
Unfortunately, only EventTriggers
can be applied directly to elements. If you want to use a Trigger
or DataTrigger
, they have to be in a Style
, ControlTemplate
, or DataTemplate
.
From the resource names, it looks like this is a Border
inside a ListBoxItem
ControlTemplate
. You could easily move the triggers into the template's triggers collection.
Here is a way for no limitations triggers.
Example:
<Border Width="130" Height="100" Grid.Row="1">
<ListBox x:Name="lstItems" ItemsSource="{Binding TestItems}">
</ListBox>
<tg:TriggerExtensions.Triggers>
<tg:TriggerCollections>
<tg:DataTriggerInfo Binding="{Binding CurrentStatus}" Value="0">
<tg:DataTriggerInfo.Setters>
<tg:SetterInfo ElementName="lstItems" Property="Style" Value="{StaticResource ListBoxRed}"/>
</tg:DataTriggerInfo.Setters>
</tg:DataTriggerInfo>
<tg:DataTriggerInfo Binding="{Binding CurrentStatus}" Value="0" IsInvert="True">
<tg:DataTriggerInfo.Setters>
<tg:SetterInfo ElementName="lstItems" Property="Style" Value="{StaticResource ListBoxBlue}"/>
</tg:DataTriggerInfo.Setters>
</tg:DataTriggerInfo>
</tg:TriggerCollections>
</tg:TriggerExtensions.Triggers>
</Border>
Link Sample
Link Component Github
精彩评论