xaml : Retrigger opacity animation on multiple conditions
- by Sdry
I have a problem figuring out how datatriggers and multidatatriggers work. I am trying to display a message, and depending on the type of message keep it displayed( + having a background), or having it fade out by a double animation on the opacity property (+ having a transparent background).
My xaml view has a game object as datacontext, which has a dependency property of type GameMessage, of which the constructor looks like this:
public GameMessage(bool containsMessage, string message, bool canFadeAway)
{
ContainsMessage = containsMessage;
Message = message;
CanFadeAway = canFadeAway;
}
pretty straight forward, I want to display the message when ContainsMessage =equals true, and trigger a fade out animation if canFadeAway equals true. But also set the background based on canFadeAway.
<Canvas Name="messageCanvas"
Width="300"
Height="100"
Style="{StaticResource fadeInOut}">
<TextBlock Name="txtMessage"
Text="{Binding Path=GameMessage.Message}"
Canvas.Top="25" Canvas.Left="0"
Foreground="{StaticResource MessageForegroundBrush}">
</TextBlock>
</Canvas>
Now, the Style and triggers is where I get into trouble:
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=GameMessage.ContainsMessage}"
Value="True"/>
<Condition Binding="{Binding Path=GameMessage.CanFadeAway}"
Value="False"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background"
Value="{StaticResource MessageBackgroundBrush}" />
<Setter Property="Opacity"
Value="8" />
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=GameMessage.ContainsMessage}"
Value="True"/>
<Condition Binding="{Binding Path=GameMessage.CanFadeAway}"
Value="True"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background"
Value="Transparent" />
<Setter Property="Opacity"
Value="8" />
</MultiDataTrigger>
<DataTrigger Binding="{Binding Path=GameMessage.CanFadeAway}"
Value="True">
<DataTrigger.EnterActions>
<BeginStoryboard >
<Storyboard BeginTime="0:0:0" >
<DoubleAnimation Storyboard.TargetProperty="Opacity"
From="8" To="0"
Duration="0:0:1" BeginTime="0:0:0" />
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
<DataTrigger.ExitActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="Opacity"
To="8" Duration="0:0:0.1" />
</Storyboard>
</BeginStoryboard>
</DataTrigger.ExitActions>
</DataTrigger>
</Style.Triggers>
</Style>
The problem is in resetting the opacity when the GameMessage Property ( of type GameMessage) is of type true,msg",true, and gets replaced by a GameMessage object of the same kind. The opcacity remains 0, and messages only get restored again when I have a message of kind true,"msg,false.
After the animation, the opacity is 0, and where I would expect the second multidatatrigger to set it back to 8, and then have the animation performed by the Datatrigger, it doesnt.
What would be the best way to get this working ?
