Consider following DataTemplate in any List Control:
<DataTemplate>
<TextBlock Text="{Binding}" />
</DataTemplate>
and following animations:
<Window.Resources>
<Storyboard x:Key="animExpand">
<DoubleAnimation Storyboard.TargetProperty="Width" To="400" Duration="0:0:1" />
<DoubleAnimation Storyboard.TargetProperty="Height" To="400" Duration="0:0:1" />
</Storyboard>
<Storyboard x:Key="animCollapse">
<DoubleAnimation Storyboard.TargetProperty="Width" To="0" Duration="0:0:1" />
<DoubleAnimation Storyboard.TargetProperty="Height" To="0" Duration="0:0:1" />
</Storyboard>
</Window.Resources>
Now we want: when any of TextBlocks get clicked, "animExpand" apply to it and all other TextBlock have a "animCollapse".
First part is straightforward (a Trigger would do it) but the question is how to make other elements take part in this scenario?
I think I would put an boolean property (IsExpanded or something) in my model and then create a datatrigger to do the animations based on that value. When a mousedown occurs on a particular item, you'd have to write the logic to updates that boolean in the other objects in the list.
Related
I have a textblock which should only show 2 lines of the text, while it is unselected. As soon as it gets selected, I want it to expand smoothly.
I started with something like:
<BeginStoryboard>
<Storyboard>
<DoubleAnimation
Storyboard.TargetName="Second"
Storyboard.TargetProperty="(TextBlock.MaxHeight)"
To="50.0" Duration="0:0:0.5" />
</Storyboard>
</BeginStoryboard>
But the issue here is, that I don't know how big the text is.
You should be able to use From='0' instead, which would start the animation with a value of 0 and end with whatever the value of MaxHeight is. However, that raises a different problem, as MaxHeight defaults to infinity, which would make the animation far too fast. Adding an ObjectAnimationUsingKeyframes at the start that sets MaxHeight to ActualHeight might work to resolve this. Something like this:
<BeginStoryboard>
<Storyboard>
<ObjectAnimationUsingKeyframes
Storyboard.TargetName='Second'
Storyboard.TargetProperty='(TextBlock.MaxHeight)'>
<DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{Binding TargetName=Second, Path=ActualHeight}" />
</ObjectAnimationUsingKeyframes>
<DoubleAnimation
Storyboard.TargetName="Second"
Storyboard.TargetProperty="(TextBlock.MaxHeight)"
From="0" Duration="0:0:0.5" />
</Storyboard>
</BeginStoryboard>
You can use DoubleAnimation to implement this. I have implemented this in a sample application.
<Window.Resources>
<Storyboard x:Key="OnGotFocus">
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="textBox" Storyboard.TargetProperty="(FrameworkElement.Height)">
<EasingDoubleKeyFrame KeyTime="0:0:2">
<EasingDoubleKeyFrame.Value>
<System:Double>NaN</System:Double>
</EasingDoubleKeyFrame.Value>
</EasingDoubleKeyFrame>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
<Storyboard x:Key="OnLostFocus">
<DoubleAnimationUsingKeyFrames Storyboard.TargetName="textBox" Storyboard.TargetProperty="(FrameworkElement.Height)">
<EasingDoubleKeyFrame KeyTime="0">
<EasingDoubleKeyFrame.Value>
<System:Double>NaN</System:Double>
</EasingDoubleKeyFrame.Value>
</EasingDoubleKeyFrame>
<EasingDoubleKeyFrame KeyTime="0:0:2" Value="30" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</Window.Resources>
<Window.Triggers>
<EventTrigger RoutedEvent="UIElement.GotFocus" SourceName="textBox">
<BeginStoryboard Storyboard="{StaticResource OnGotFocus}" />
</EventTrigger>
<EventTrigger RoutedEvent="UIElement.LostFocus" SourceName="textBox">
<BeginStoryboard x:Name="OnLostFocus_BeginStoryboard" Storyboard="{StaticResource OnLostFocus}" />
</EventTrigger>
</Window.Triggers>
Your code for textbox should be :
<TextBox x:Name="textBox"
Height="30"
HorizontalAlignment="Right"
Text="Hello World" />
This will animate the textbox to a specified height as soon as it gets focussed. I have added an animation to collapse it as well when it loses focus.
Hope this helps you.
I'm looking for a way to set a Property after it was animated, in pure xaml.
Msdn has an example of how to do that in xaml + codebehind :
XAML:
<Button
Content="Animate and Then Set Example 1">
<Button.Background>
<SolidColorBrush x:Name="Button1BackgroundBrush"
Color="Red" />
</Button.Background>
<Button.Triggers>
<EventTrigger RoutedEvent="Button.Click">
<BeginStoryboard>
<Storyboard>
<ColorAnimation
Storyboard.TargetName="Button1BackgroundBrush"
Storyboard.TargetProperty="Color"
From="Red" To="Yellow" Duration="0:0:5"
FillBehavior="HoldEnd"
Completed="setButton1BackgroundBrushColor" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Button.Triggers>
</Button>
C#:
private void setButton1BackgroundBrushColor(object sender, EventArgs e)
{
Button1BackgroundBrush.Color = Colors.Blue;
}
In this particular case you could add another ColorAnimation and delay it appropriately via its BeginTime property, like so:
<Storyboard>
<ColorAnimation
Storyboard.TargetName="Button1BackgroundBrush"
Storyboard.TargetProperty="Color"
From="Red" To="Yellow" Duration="0:0:5" />
<ColorAnimation
Storyboard.TargetName="Button1BackgroundBrush"
Storyboard.TargetProperty="Color"
To="Blue" Duration="0"
BeginTime="0:0:5" />
</Storyboard>
In more general case, depending on the property type, you could use appropriate animation, if one exists, in analogous way.
I have a textblock which should react for changing its text (it must display text for few seconds, and then dissapear).
<TextBlock Text="{Binding Path=OperationMessage, NotifyOnValidationError=True}" x:Name="label_OperationMessage" Visibility="Collapsed" HorizontalAlignment="Right" Margin="3,3,3,3" >
<TextBlock.Triggers>
<EventTrigger RoutedEvent="Binding.TargetUpdated">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="Opacity" Duration="0:0:0" To="1.0" />
<DoubleAnimation Storyboard.TargetProperty="Opacity" Duration="0:0:2" From="1.0" To="0.0" BeginTime="0:0:5" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</TextBlock.Triggers>
</TextBlock>
When I launch my app I get error :
Failed to assign to property 'System.Windows.EventTrigger.RoutedEvent'.
on the line
<EventTrigger RoutedEvent="Binding.TargetUpdated">
What is wrong with this code?
The only event supported by Silverlight for use in the Triggers property is the Loaded event. Anything else will result in this exception.
To acheive this sort of Xaml event logic you can download the Blend SDK which contains all manner of useful features like this. In your case you are looking for the PropertyChangedTrigger.
I'm triying to hide/show a stackpanel when I click in a button. This is what I made so far:
<Button.Triggers>
<EventTrigger RoutedEvent="Mouse.PreviewMouseDown">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="Height"
Storyboard.TargetName="PanelDeCampos"
From="{Binding ElementName=PanelDeCampos,Path=ActualHeight}"
To="0"
Duration="0:0:0.25" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Button.Triggers>
This animation works well, and it hides the panel when I click on it. But now I need to find a way to launch the reverse animation when the button is clicked again. Could I store the current state and decide what animation launch or something like this?
Thanks.
You can change your button to a ToggleButton and use the Checked and Unchecked routed events to set up your 2 storyboards:
<ToggleButton>
<ToggleButton.Triggers>
<EventTrigger RoutedEvent="Checked">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="Height"
Storyboard.TargetName="PanelDeCampos"
From="{Binding ElementName=PanelDeCampos,Path=ActualHeight}"
To="0"
Duration="0:0:0.25" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<EventTrigger RoutedEvent="Unchecked">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="Height"
Storyboard.TargetName="PanelDeCampos"
From="0"
Duration="0:0:0.25"
To="1000" /> <!-- or whatever height you want-->
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</ToggleButton.Triggers>
</ToggleButton>
What about a little trick:
Together with the storyboard you have in place now, you are hidding the current button and setting another button (which looks the same) visible.
The other button has the reverse storyboard, and reverse button visibility settings.
With that you don't have to worry about a state, and you can do it only in XAML.
Other Idea would be to handle the click in the code behind, maintain a flag there, and trigger the storyboard from the code. As this is a view-only functionality I don't see a conflict with MVVM.
I have a WPF usercontrol set up in XAML with the following Triggers:
<UserControl.Triggers>
<EventTrigger RoutedEvent="GotFocus">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="1.5" Storyboard.TargetName="ImageContent" Storyboard.TargetProperty="RenderTransform.Children[1].ScaleX" Duration="0:0:0.8" />
<DoubleAnimation To="1.5" Storyboard.TargetName="ImageContent" Storyboard.TargetProperty="RenderTransform.Children[1].ScaleY" Duration="0:0:0.8" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<EventTrigger RoutedEvent="LostFocus">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="1" Storyboard.TargetName="ImageContent" Storyboard.TargetProperty="RenderTransform.Children[1].ScaleX" Duration="0:0:0.8" />
<DoubleAnimation To="1" Storyboard.TargetName="ImageContent" Storyboard.TargetProperty="RenderTransform.Children[1].ScaleY" Duration="0:0:0.8" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</UserControl.Triggers>
The Animation is working fine but unfortunately the Triggers arent working as expected. The GotFocus trigger only fires if i Right-Click my Control or if i Click a Button that is contained within the UserControl.
I have created an EventHandler for the GotFocus event in code and that seems to fire in the right places.
Edit: If I change it to Fire on MouseEnter / Leave it also works as expected
Edit2: I foudn out that this behaviour is surfacing because the Control gets focus, but loses the focus again right away. I fixed it by adding some code, that checks if the source of the Event is the UserControl or something else.
Any hints on why this is happening would be appreciated.
Try settings Focusable="True" on the UserControl.