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MVVM How bind MouseLeftButtonDown and MouseLeftButtonUp in Canvas

Im trying to add new child(circle) to my Canvas after user click on it. And i want to change position of circles while draging them.
I want to do it with MVVM but dont know how catch these events in ViewModel.
I need a MouseLeftButtonUp/Down
I've tried wih System.Windows.Interactivity but it didnt helped.
My only idea is to add invisible button and do easy binding Command="{Binding Method}", but it still wont solve my problem, and certainly its not a best option
This in my XAML code (part of it)
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
<Canvas x:Name="DrawableCanvas" HorizontalAlignment="Left" Height="{Binding ElementName=GridContainer, Path=ActualHeight}" VerticalAlignment="Top" Width="{Binding ElementName=GridContainer, Path=ActualWidth}" Background="{DynamicResource {x:Static SystemColors.ControlBrushKey}}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseLeftButtonDown">
<i:InvokeCommandAction Command="{Binding CanvasActionCommand}" x:Name="interactifityFix2">
</i:InvokeCommandAction>
</i:EventTrigger>
</i:Interaction.Triggers>
</Canvas>

Add this namespace in your XAML:
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
then you can add an interaction trigger wich will merge the event with an icommand in your viemodel like so:
<Ellipse>
<i:Interaction.Triggers>
<i:EventTrigger EventName="PreviewMouseDown">
<i:InvokeCommandAction Command="{Binding MouseDownCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Ellipse>

Triggering a command with a command target

*I'm using Material Design though this shouldn't be relative to the question
<ScrollViewer>
<ListView>
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseDoubleClick">
<i:InvokeCommandAction Command="{x:Static materialDesign:DialogHost.OpenDialogCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</ListView>
</ScrollViewer>
Sofar I've gotten it to trigger the command on double click, although I want to also set a command target property like:
CommandTarget="{Binding ElementName=addhost}"

Button inside the GridSplitter not working WPF MVVM

I put the button inside the gridsplitter. my intention is to make clickable gridsplitter as well as slideable. my problem is after putting button inside the grid splitter, totally cannot drag by mouse. how can i configure the grid splitter to clickable and slideable.
<GridSplitter BorderThickness="1" HorizontalAlignment="Stretch" Grid.Column="1" >
<GridSplitter.Template>
<ControlTemplate TargetType="{x:Type GridSplitter}">
<Grid>
<Button Name="btnSplit" Content="⁞" >
<i:Interaction.Triggers>
<i:EventTrigger EventName="Click">
<i:InvokeCommandAction Command="{Binding SplitterClickCommand}" CommandParameter="{Binding ElementName=btnSplit}" ></i:InvokeCommandAction>
</i:EventTrigger>
</i:Interaction.Triggers>
</Button>
</Grid>
</ControlTemplate>
</GridSplitter.Template>
</GridSplitter>
Best Rgds
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Try to subscribe MouseDoubleClick event on GridSplitter:
<GridSplitter BorderThickness="1" HorizontalAlignment="Stretch" Grid.Column="1" >
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseDoubleClick">
<i:InvokeCommandAction Command="{Binding SplitterClickCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</GridSplitter>
If MouseDoubleClick event is not suitable for you, you can try to subscribe to MouseDown or MouseLeftButtonDown.

eventtocommand ManipulationCompleted

I'm having a go at writing a small media player for my Windows Phone (more for learning purposes if anything), and am using mvvm-light.
When a video is playing, I have a timer that periodically updates the slider position (and ensures that it's in sync). When I slide the slider around, I pause the timer, so it doesn't skip about.
I use the ManipulationStarted event to pause the timer, and ManipulationComplete to resume it.
I've tried using EventToCommand, but only the ManipulationStarted event fires. When I lift my finger off the phone, ManipulationComplete doesn't fire.
This is my xaml :
<Slider x:Name="PlaybackSlider" HorizontalAlignment="Stretch" Margin="20,0" VerticalAlignment="Bottom" Maximum="{Binding MaxSteps}" Value="{Binding Offset, Mode=TwoWay}" Style="{StaticResource SliderStyle1}" >
<i:Interaction.Triggers>
<i:EventTrigger EventName="ManipulationStarted">
<Command:EventToCommand Command="{Binding PlayOffsetBegin}"/>
</i:EventTrigger>
<i:EventTrigger EventName="ManipulationCompleted">
<Command:EventToCommand Command="{Binding PlayOffsetEnd}"/>
</i:EventTrigger>
<i:EventTrigger EventName="MouseMove">
<Command:EventToCommand Command="{Binding PlayOffsetUpdate}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</Slider>
The bindings are relay commands.
If I implement it like this, it all works fine :
<Slider x:Name="PlaybackSlider"
ManipulationStarted="PlaybackSlider_ManipulationStarted"
ManipulationCompleted="PlaybackSlider_ManipulationCompleted"
HorizontalAlignment="Stretch" Margin="20,0" VerticalAlignment="Bottom"
Maximum="{Binding MaxSteps}" Value="{Binding Offset, Mode=TwoWay}"/>

Binding toggle button to two commands

I have a toggle button in my silverlight application as follows:
<ToggleButton Content="ToggleButton" Margin="0,30,0,0" Style="{StaticResource ChkToggleButton}" />
The toggle currently is changing visual states on toggle and nothing more.
However, I need to bind each of the toggle with a different command. For eg: On button press1, run command1 and on button press again, run command2.
How can this be done?

Use Triggers for such purposes:
<ToggleButton Content="ToggleButton" Margin="0,30,0,0" Style="{StaticResource ChkToggleButton}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Checked">
<i:InvokeCommandAction Command="{Binding FirstCommand}"
CommandParameter="{Binding SomeParameter}" />
</i:EventTrigger>
<i:EventTrigger EventName="Unchecked">
<i:InvokeCommandAction Command="{Binding SecondCommand}"
CommandParameter="{Binding AnotherParameter}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</ToggleButton>
If you don't have Interactivity you can get it by installing Expression Blend SDK or as a NuGet package.

use a single command and also keep track of the toggle state.
Have a viewmodel (preferably, or some codebehind) and let it use these two inputs to decide what actually needs to be done.