How to 'Freeze' the UI (main window) when mouse is hovering over - wpf

What I want to achieve is that when the mouse is hovering over the main window, all the UI elements should freeze, which I think can be done by setting Window.IsEnabled to false, and after the mouse leaves the main window, everything should be back to normal.
I've tried to define a property trigger in a style targetting Window, but it doesn't work. The code is as lollow,
<Style.Triggers>
<Trigger Property="Window.IsMouseOver" Value="True">
<Setter Property="Window.IsEnabled" Value="false"/>
</Trigger>
</Style.Triggers>
In fact this kind of property trigger wouldn't work on Grid either. Can anyone make some explanations?
I also tried to explicitly use the MouseEnter and MouseLeave events on Window, and set the disable/enable logic in the handlers. This works. I wonder if it's possible to do this in XAML?

Well to be honest I don't know why your code doesn't work, I think it goes in some kind of conflict but I don't know why
Anyway you can do it in XAML using eventsetter, It's not so elegant but it works
<Window.Triggers>
<EventTrigger RoutedEvent="Window.MouseEnter">
<BeginStoryboard>
<Storyboard Name="sb">
<BooleanAnimationUsingKeyFrames Storyboard.TargetProperty="IsEnabled" >
<BooleanKeyFrameCollection>
<DiscreteBooleanKeyFrame Value="False" KeyTime="0:0:0:1"></DiscreteBooleanKeyFrame>
</BooleanKeyFrameCollection>
</BooleanAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Window.Triggers>

Related

Blink animation style for period of time

So i have StackPanel that i want to show with blink Style for several seconds and after that i want it to disappear.
I do not want it to be Automatically but control it from code behind:
So currently this is what i have so far:
<Style x:Key="FaderStyle" TargetType="{x:Type StackPanel}">
<Style.Resources>
<Storyboard x:Key="FadeStoryboard">
<DoubleAnimation Storyboard.TargetProperty="(StackPanel.Opacity)"
From="0"
To="1" Duration="0:0:0.7"
RepeatBehavior="0:0:5"
AutoReverse="True"/>
</Storyboard>
</Style.Resources>
<Style.Triggers>
<Trigger Property="Visibility" Value="Visible">
<Trigger.EnterActions>
<BeginStoryboard Storyboard="{StaticResource FadeStoryboard}"/>
</Trigger.EnterActions>
</Trigger>
</Style.Triggers>
</Style>
Code behind:
StackPanel sp;
Storyboard storyboard = Resources["FaderStyle"] as Storyboard;
if (storyboard != null)
storyboard.Begin(sp);
So currently my StackPanel Visibility is Collapsed and after i start the Animation i still cannot see it.
Your code is fine. But your approach to starting the animation is wrong. The trigger starts the animation when Visibility changes to Visible. Not the other way around (which your last piece of code indicates) starting the animation does not change visibility because you didn't write the logic to do that
So with your given code, you need to change the visibility in order to start the animation:
StackPanel sp;
sp.Visibility = Visibility.Visible;
Note that the animation only starts when it enters Visible state. Which means you need to make it collapsed or hidden first.

Time Delay on Trigger

I wish to attach a time delay to a mouseover event on a WPF expander I have on my form (xaml supported by VB.NET code behind). This mouseover event essentially triggers the expansion as oppose to clicking - but I'd like a short wait before the content is expanded. So far I have not managed to find anything to solve this via the wider internet.
The current xaml code to enable the trigger is:
<Style x:Key="HoverExpander" TargetType="{x:Type Expander}">
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="IsExpanded" Value="True" />
</Trigger>
</Style.Triggers>
</Style>
This style is then applied to:
<Expander Style="{StaticResource HoverExpander}"
HorizontalAlignment="Right"
ExpandDirection="Left"
Height="Auto"
Width="Auto">
<!-- Content here -->
</Expander>
Note that I've stripped out other aesthetics (such as borders, gridrefs etc for readability).
I think there should be some way to set a delay on the MouseOver Trigger but haven't had much luck finding it. This could either be set in xaml or perhaps as an event in the code behind.
I'm working on this currently, so when I find a solution I shall post it here. Grateful for any ideas meantime. Thanks!
Use an EventTrigger on the MouseOver event and a Storyboard with a BooleanAnimationUsingKeyFrames instead. In the Timeline of the Storyboard, you could have KeyFrames, so that the animation waits for some time before it affects the properties you want to change.
This was the code I settled on - based on the ideas already given:
<Style x:Key="HoverExpander" TargetType="{x:Type Expander}">
<Style.Setters>
<Setter Property="IsExpanded" Value="False"/><!-- Initially collapsed -->
</Style.Setters>
<Style.Triggers>
<!-- Impose a short delay (500ms) before expanding control -->
<EventTrigger RoutedEvent="Expander.MouseEnter">
<BeginStoryboard>
<Storyboard>
<BooleanAnimationUsingKeyFrames
Storyboard.TargetProperty="IsExpanded"
Duration="0:0:0.5">
<DiscreteBooleanKeyFrame Value="True" KeyTime="100%"/><!-- I.E. after 500ms -->
</BooleanAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<!-- Collapse when mouse leaves control-->
<EventTrigger RoutedEvent="Expander.MouseLeave">
<BeginStoryboard>
<Storyboard>
<BooleanAnimationUsingKeyFrames
Storyboard.TargetProperty="IsExpanded"
Duration="0:0:0.1">
<DiscreteBooleanKeyFrame Value="False" KeyTime="0%"/><!-- I.E. Immediately -->
</BooleanAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Style.Triggers>
</Style>
Then apply as before. This was tested and works in .NET 4.0. Other neat tricks could be applied if you do so wish, I found the following to be quite helpful in getting ideas:
Animation Overview (MSDN)
Storyboards Overview (MSDN)

DataTrigger don't seems to fire

I want to create a datatrigger that makes my page blink (from transparent to red). So I created a DataTrigger that listens to a boolean flag within my viewmodel. This flag shall indicate whenever the user needs to be reminded. In that case, my page shall blink from transparent to red.
I was pretty sure that I have implemented the data trigger in a correct manner, but my app does nothing - no error, no blinking... So I must have something missed.
<Style x:Key="ReminderPage" TargetType="{x:Type ViewTemplates:TpApplicationBarView}" BasedOn="{StaticResource TpApplicationBarViewStyle}">
<Style.Triggers>
<!-- Reminder animation, when the time comes to remind the user -->
<DataTrigger Binding="{Binding IndicateReminderAnimation}" Value="True">
<DataTrigger.EnterActions>
<BeginStoryboard>
<Storyboard x:Name="Blink">
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
AutoReverse="True"
From="Transparent"
To="Red"
Duration="0:0:1"
RepeatBehavior="Forever">
</ColorAnimation >
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
</DataTrigger>
<DataTrigger Binding="{Binding IndicateReminderAnimation}" Value="False">
<DataTrigger.EnterActions>
<BeginStoryboard>
<Storyboard>
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
AutoReverse="False"
To="Transparent"
Duration="0:0:1">
</ColorAnimation >
</Storyboard>
</BeginStoryboard>
</DataTrigger.EnterActions>
</DataTrigger>
</Style.Triggers>
</Style>
So, what do I have done wrong?
Update: I can see the following message in the output window:
System.Windows.Media.Animation Warning: 6 : Unable to perform action because
the specified Storyboard was never applied to this object for interactive control.;
Action='Stop'; Storyboard='System.Windows.Media.Animation.Storyboard';
Storyboard.HashCode='61356140'; Storyboard.Type='System.Windows.Media.Animation.Storyboard';
TargetElement='System.Windows.Media.Animation.Storyboard'; TargetElement.HashCode='61356140';
TargetElement.Type='System.Windows.Media.Animation.Storyboard'
Update2: After googling arround I found out, that it is a problem with the UI Thread. So I made a dispatcher call whenever I set the bound property. But even with this trick, there's no color animation. But the error in the output window seems to be vanished. So, I'm searching for further ideas on how to fix the animation.
Update3: It seems to be a general problem setting the background color of the page. But it's really strange. The Page is placed in a NavigationFrame. Setting the background color of the navigation frame will change the color of the application, but setting the background color of the page (even without any animation) won't change anything.
I think you will have to set the animations Target, something like this -
Storyboard.TargetName="yourWindowName"
You may have already checked this, but make sure that correct object is set as your TpApplicationBarView's DataContext(having IndicateReminderAnimation property).
I found the bug - or better the two bugs.
1.) It seems not be possible to change the background color of a page that is placed within a Navigation Frame.
So first was to move the binding and event to the MainWindow itself (wpf window class)
2.) The Style that contains the data trigger did not work. After googling around I found a working solution for what I'm searching for.
<Storyboard x:Key="RemindUser" >
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
AutoReverse="True"
From="Transparent"
To="{StaticResource WinAccentBackgroundColor}"
Duration="0:0:1"
RepeatBehavior="Forever">
</ColorAnimation >
</Storyboard>
<Storyboard x:Key="StopRemindUser">
<ColorAnimation Storyboard.TargetProperty="(Background).(SolidColorBrush.Color)"
AutoReverse="True"
To="Transparent"
Duration="0:0:1">
</ColorAnimation >
</Storyboard>
<Style x:Key="ReminderWindow" TargetType="{x:Type Metro:SnappedTransparentWindow}" BasedOn="{StaticResource TransparentWindow}">
<Style.Triggers>
<!-- Reminder animation, when the time comes to remind the user -->
<DataTrigger Binding="{Binding IndicateReminderAnimation}" Value="True">
<DataTrigger.EnterActions>
<BeginStoryboard Storyboard="{StaticResource RemindUser}"/>
</DataTrigger.EnterActions>
<DataTrigger.ExitActions>
<BeginStoryboard Storyboard="{StaticResource StopRemindUser}"/>
</DataTrigger.ExitActions>
</DataTrigger>
</Style.Triggers>
</Style>
The key was to split the binding and storyboard into different parts.

Synchronize WPF ColorAnimation across several controls

I have several toggle-like buttons that I want to pulsate in unison when in the pressed state.
I have defined a style with a trigger that kicks-off the glow animation and this works just fine, apart from the fact that each button pulsates asynchronously from the others.
How can I have each button synchronize its pulse to the others?
Here's the style:
<Storyboard x:Key="pulseStory">
<ColorAnimation
Storyboard.TargetProperty="(Control.Background).(SolidColorBrush.Color)"
From="Red"
To="Transparent"
Duration="0:0:1" />
</Storyboard>
<Style x:Key="pulseButton" TargetType="Button">
<Style.Triggers>
<DataTrigger Binding="{Binding Tag,RelativeSource={RelativeSource Self}}" Value="True">
<DataTrigger.EnterActions>
<BeginStoryboard Storyboard="{StaticResource pulseStory}"/>
</DataTrigger.EnterActions>
</DataTrigger>
</Style.Triggers>
</Style>
Cheers!
OK ... I'll take a stab at this one ...
The WPF framework doesn't have any facility for synchronizing animations that are running concurrently, so you are going to have to come up with a different method. One idea springs to mind ...
Animate some Color property of a hidden UI element within your storyboard, then use UI binding (i.e. ElementName bindings) to connect to the Color of each of your buttons to this hidden UI element.
Actually you should be doing this via a resource, at least using a hidden control is a bit too much of a hack for me personally.
What needs to be met for it to work:
The property you bind to needs to be a DependencyProperty, hence your enveloping object needs to be a DependencyObject.
You have to reference the object as a static resource (as opposed to a dynamic resource) like this:
<DoubleAnimation
Storyboard.Target="{StaticResource AnimationValue}"
Storyboard.TargetProperty="(local:WrappedValue.Value)"
To="0" Duration="0:0:1"/>
Well, admittedly it's a bit hacky as well to have a Wrapper-class for this but it's cleaner than a full control (if you want to use controls you can utilize some unused Tag-property, e.g. of the container that hosts all your controls)

Begin Storyboard on more than one target

I have a subclassed ListBox with a SelectedItemChanging dependency property that is set to a Storyboard. When the selected item is changed, I want to run this Storyboard on each item in the ListBox.
How is this possible with a single instance of Storyboard?
Storyboards can be keyed and run from multiple triggers, and it works great as long as it's set up properly. If I am understanding you correctly, you're hoping to apply the storyboard to each individual ListBoxItem. In which case, why not make a style, and on that style's triggers, fire the storyboard.
Excuse my pseudocode.
<Storyboard x:Key="MyEnterStoryboard">
<!-- Do Enter Work -->
</Storyboard>
<Storyboard x:Key="MyExitStoryboard">
<!-- Do Exit Work -->
</Storyboard>
<Style TargetType="{x:Type ListBoxItem}">
<Style.Triggers>
<Trigger Property="SelectedItemChanging" Value="True">
<Trigger.EnterActions>
<BeginStoryboard Storyboard="{StaticResource MyEnterStoryboard}"/>
</Trigger.EnterActions>
<Trigger.ExitActions>
<BeginStoryboard Storyboard="{StaticResource MyExitStoryboard}"/>
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
WPF Storyboards have a Clone method. Silverlight doesn't have this but thought I'd post it just in case someone stumbles across this post looking for a WPF solution.

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