WPF Animation To dynamic value - wpf

I want show up a UserControl occasionally.
When the visibility of the UserControl is changed to visible, it should ease in in a moderate speed.
I figured out how to to this basically:
<UserControl.Resources>
<Style TargetType="{x:Type UserControl}" x:Key="MyStyleName">
<Style.Triggers>
<Trigger Property="Visibility" Value="Visible">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="Height" From="0.0" To="200.0" Duration="0:0:1" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
</UserControl.Resources>
This works fine.
In the real world application, I don't know the exact value of the Height property, because the UserControl is "hosted" in a Grid and the row height is set to "Auto".
I've tried to do a Binding to the TemplatedParent, doesn't work. A Binding to a RelativeSource doesn't work either.
Can anyone help me, please?
Thanks!

As an alternative, animate a ScaleTransform in the control's RenderTransform:
<Style TargetType="UserControl">
<Setter Property="RenderTransformOrigin" Value="0.5,0.5"/>
<Setter Property="RenderTransform">
<Setter.Value>
<ScaleTransform ScaleY="0"/>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Visibility" Value="Visible">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="1" Duration="0:0:1"
Storyboard.TargetProperty="RenderTransform.ScaleY"/>
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>

Related

Change background of all the textblocks in a Page to Transparent by clicking on a textblock and change the background of clicked textblock to Blue

I have my problem half solved.
Look at the below code:
<Style TargetType="TextBlock">
<Style.Triggers>
<EventTrigger RoutedEvent="MouseDown">
<EventTrigger.Actions>
<BeginStoryboard>
<Storyboard>
<ColorAnimation Storyboard.TargetProperty="Background.Color" To="Blue" Duration="0:0:0.100" />
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Style.Triggers>
</Style>
As you can see in the above style, I can change the background of a clicked textblock to Blue. But I also want to change the background of other textblocks to Transparent.
It seems u want to change style of only selected textblock . You can use listbox for your requirement as listbox item is having style for selected and unselected item.
Maybe I am wrong..but try this.this is might be helpful.
I have used different color in style ..You can use own colors as per your requirement
<Style x:Key="listbox_Item" TargetType="{x:Type ListBoxItem}">
<Setter Property="SnapsToDevicePixels" Value="True"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<Grid>
<Border Margin="10" x:Name="BorderStyle" Background="Transparent" BorderBrush="Red" BorderThickness="1"/>
<ContentPresenter></ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="false">
<Trigger.EnterActions>
<BeginStoryboard x:Name="unselectedAnimation">
<Storyboard >
<ColorAnimation Storyboard.TargetName="BorderStyle" Storyboard.TargetProperty="BorderBrush.Color" From="Transparent" To="Green" Duration="0:0:0.1"></ColorAnimation>
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="unselectedAnimation" />
</Trigger.ExitActions>
</Trigger>
<Trigger Property="IsSelected" Value="true">
<Trigger.EnterActions>
<BeginStoryboard x:Name="selectedAnimation">
<Storyboard>
<Storyboard >
<ColorAnimation Storyboard.TargetName="BorderStyle" Storyboard.TargetProperty="BorderBrush.Color" From="Transparent" To="Red" Duration="0:0:0.1"></ColorAnimation>
</Storyboard>
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<StopStoryboard BeginStoryboardName="selectedAnimation"/>
</Trigger.ExitActions>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground"
Value="Red"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
and behind code u need to create a class and itemsouce for listbox
InitializeComponent();
List<tileproperty> abc = new List<tileproperty>();
abc.Add(new tileproperty("ssss", "dssds"));
abc.Add(new tileproperty("ssss", "dssds"));
lst.ItemsSource = abc;
}
public class tileproperty
{
public string next { get; set; }
public string path { get; set; }
public tileproperty(string next, string path)
{
this.next = next;
this.path = path;
}
}

ListBoxItem in WPF - scale animation when selected

I have a ListBox with customized item's style. I want the item to grow a bit when selected, and go back to its original size when deselected. I've tried several solutions but none seemed to work. I think the problem lies in the proper setting of Storyboard.TargetProperty.
My current XAML looks like this:
...
<ListBox.Resources>
<Style TargetType="{x:Type ListBoxItem}">
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="LayoutTransform.(ScaleTransform.ScaleX)" To="1.2" Duration="0:0:.3" AutoReverse="True"/>
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
</ListBox.Resources>
...
My final code (with answers applied):
...
<ListBox.Resources>
<Style TargetType="{x:Type ListBoxItem}">
<Setter Property="RenderTransformOrigin" Value="0.5,0.5" />
<Setter Property="RenderTransform">
<Setter.Value>
<ScaleTransform />
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="RenderTransform.ScaleX" To="1.1" Duration="0:0:.1" />
<DoubleAnimation Storyboard.TargetProperty="RenderTransform.ScaleY" To="1.1" Duration="0:0:.1" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
<Trigger.ExitActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="RenderTransform.ScaleX" To="1.0" Duration="0:0:.1" />
<DoubleAnimation Storyboard.TargetProperty="RenderTransform.ScaleY" To="1.0" Duration="0:0:.1" />
</Storyboard>
</BeginStoryboard>
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
</ListBox.Resources>
...
Try using following code:
...
<ListBox.Resources>
<Style TargetType="{x:Type ListBoxItem}">
<Setter Property="LayoutTransform">
<Setter.Value>
<ScaleTransform x:Name="scaleTransform" />
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="LayoutTransform.ScaleX" To="1.2" Duration="0:0:.3" AutoReverse="True"/>
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
</ListBox.Resources>
...

How to change multiple properties on mouseover

I've just started with WPF (I'm sorry if the question is too obvious), and I managed to put together this mouseover style. The background color animates to a darker color. I now want to also animate the text to white, so it's easier to read.
This is how I tried to add it, but it gives me the error "Cannot resolve all property references in the property path 'TextBlock.Foreground'. Verify that applicable objects support the properties" when I mouseover it.
<Border Background="#e6ebf3" CornerRadius="0,10,0,10" >
<Border.Style>
<Style TargetType="Border">
<Setter Property="Background" Value="#e6ebf3" />
<Setter Property="TextBlock.Foreground" Value="Black"/>
<Style.Triggers>
<EventTrigger RoutedEvent="UIElement.MouseEnter">
<BeginStoryboard>
<Storyboard>
<ColorAnimation Duration="0:0:0.1" Storyboard.TargetProperty="Background.Color" To="#6d809b" />
<ColorAnimation Duration="0:0:0.1" Storyboard.TargetProperty="TextBlock.Foreground" To="white" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<EventTrigger RoutedEvent="UIElement.MouseLeave">
<BeginStoryboard>
<Storyboard>
<ColorAnimation Duration="0:0:0.1" Storyboard.TargetProperty="Background.Color" To="#e6ebf3" />
<ColorAnimation Duration="0:0:0.1" Storyboard.TargetProperty="TextBlock.Foreground" To="Black" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Style.Triggers>
</Style>
</Border.Style>........
I found an alternative way without using storyboard or animations, so I'll post it just in case. Still wondering about the original one, though.
<Border CornerRadius="0,10,0,10" >
<Border.Style>
<Style TargetType="Border">
<Setter Property="Background" Value="#e6ebf3" />
<Setter Property="TextBlock.Foreground" Value="Black"/>
<Style.Triggers>
<Trigger Property ="IsMouseOver" Value="True">
<Setter Property= "Background" Value="#6d809b"/>
<Setter Property= "TextBlock.Foreground" Value="White"/>
</Trigger>
</Style.Triggers>
</Style>
</Border.Style>
...
Indirect property targeting, that being TextBlock.Foreground is described here http://msdn.microsoft.com/en-us/library/ms742451.aspx. It's basically saying, "hey I couldn't find a property called TextBlock on type button." It works with Background.Color because the Background Property does exist on Button and it's of type ColorBrush which itself has a property of type Color.

How to animate ScaleY when Element becomes visible

I'd like to make a WPF UI Element appear to expand vertically when its Visibility property transitions to "Visible". I don't want to hard-code the Height in the animation since I'd like to apply this animation to any UI Element as a Style. So, I'm trying to use ScaleY but am not having any luck. Here is the XAML for the style and the listbox:
<Style x:Key="VerticalGrow" TargetType="ListBox">
<Style.Triggers>
<Trigger Property="Visibility" Value="Visible">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Storyboard.TargetProperty="TransformGroup.ScaleTransform.ScaleY" BeginTime="0:0:0.5" From="0" To="1" Duration="0:0:0.5" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
<ListBox Grid.Row="2" MaxHeight="60" MinHeight="60" Visibility="{Binding MyViewModel.ListBoxVisibility}" IsSynchronizedWithCurrentItem="False" ItemsSource="{Binding MyViewModel.ListBoxItems}" Style="{DynamicResource VerticalGrow}" IsTabStop="True">
</ListBox>
I get an runtime exception complaining that:
"Cannot convert the value in attribute 'Style' to object of type 'System.Windows.Style'. Cannot resolve all property references in the property path 'TransformGroup.RenderTransform.ScaleTransform.ScaleY'. Verify that applicable objects support the properties. Error at object 'System.Windows.Controls.ListBox' in markup file 'MyApp;component/mainwindow.xaml' Line 69 Position 399."}
ListBox doesn't have a property TransformGroup. I think you want to set RenderTransform or LayoutTransform to a ScaleTransform, and then animate that.
<Style x:Key="VerticalGrow" TargetType="ListBox">
<Setter Property="RenderTransform">
<Setter.Value>
<ScaleTransform/>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Visibility" Value="Visible">
<Trigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation
Storyboard.TargetProperty="RenderTransform.ScaleY"
BeginTime="0:0:0.5" From="0" To="1" Duration="0:0:0.5" />
</Storyboard>
</BeginStoryboard>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>

WPF - Best way of responding to changes in a ViewModel at Page/Window level

I'm developing an XBAP and i have a simple requirement.
The DataContext of the whole main page is set to an instance of my UserViewModel. The UserViewModel has a DependencyProperty called AuthenticationState which is an enum with values like 'Authenticated','NotAutheticated' and 'AuthenticationFailed'.
Now, i need to respond to any change in this value by hiding/displaying various elements on the page.
What (and where) is the best way of doing that?
As you mentioned you can't use a DataTrigger directly on a control. A work around would be to use a style on each Control that needs to be hidden.
<Grid>
<Rectangle Fill="Red" />
<Grid.Style>
<Style TargetType="Grid">
<Style.Triggers>
<DataTrigger Binding="{Binding Test}" Value="true">
<Setter Property="Visibility" Value="Collapsed" />
</DataTrigger>
</Style.Triggers>
</Style>
</Grid.Style>
</Grid>
A preferable method would be to use a Converter called "AuthenticationStateToVisibilityConverter" that is used in binding the control's Visibility property to the data context's AuthenticationState property.
The best way would be to use a DataTrigger. So something like this:
<Window.Triggers>
<DataTrigger Binding="{Binding AuthenticationState}" Value="NotAuthenticated">
<Setter TargetName="nameOfControl" Property="Visibility" Value="Collapsed" />
</DataTrigger>
...
<TextBox x:Name="nameOfControl" />
</Window.Triggers>
As long as you UserViewModel object is in the DataContext of the Window then this should work!
Managed to sort it using styles. It's a pain but it works!
The full source is below.
<Grid x:Name="contentGrid" Grid.Row="1">
<!--login-->
<controls:LoginControl>
<controls:LoginControl.Style>
<Style>
<Setter Property="Control.Opacity" Value="0"/>
<Setter Property="Control.IsHitTestVisible" Value="False"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Source={StaticResource UserViewModel},Path=UserAuthenticationState}"
Value="{x:Static model:AuthenticationState.NotAuthenticated}">
<Setter Property="Control.IsHitTestVisible" Value="True"/>
<DataTrigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="1" Duration="0:0:2"
Storyboard.TargetProperty="Opacity"></DoubleAnimation>
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
<DataTrigger.ExitActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="0" Duration="0:0:2"
Storyboard.TargetProperty="Opacity"></DoubleAnimation>
</Storyboard>
</BeginStoryboard>
</DataTrigger.ExitActions>
</DataTrigger>
</Style.Triggers>
</Style>
</controls:LoginControl.Style>
</controls:LoginControl>
<!--slider-->
<slider:PageSlider>
<Button>1</Button>
<Button>2</Button>
<Button>3</Button>
<slider:PageSlider.Style>
<Style>
<Setter Property="Control.Opacity" Value="0"/>
<Setter Property="Control.IsHitTestVisible" Value="False"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Source={StaticResource UserViewModel},Path=UserAuthenticationState}"
Value="{x:Static model:AuthenticationState.Authenticated}">
<Setter Property="Control.IsHitTestVisible" Value="True"/>
<DataTrigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="1" Duration="0:0:2"
Storyboard.TargetProperty="Opacity"></DoubleAnimation>
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
<DataTrigger.ExitActions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation To="0" Duration="0:0:2"
Storyboard.TargetProperty="Opacity"></DoubleAnimation>
</Storyboard>
</BeginStoryboard>
</DataTrigger.ExitActions>
</DataTrigger>
</Style.Triggers>
</Style>
</slider:PageSlider.Style>
</slider:PageSlider>
</Grid>
Actually, the best way to do this is to expose the appropriate properties from your view model. This makes your logic more centralized and easier to test. Also, it performs better than converters. It is, after all, a view model. Therefore, it should model the view. If the view needs a property to tell it when to hide / show a panel, add such a property to your view model.

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