Binding commands to ToggleButton Checked and Unchecked events - wpf

Question

I have a ToggleButton in my C# WPF application where I would like to bind one Command to the Checked event and one Command to the Unchecked event.
What I have currently is the following:
<ToggleButton Name="btnOpenPort" Style="{StaticResource myOnOffBtnStyle}" Content="Open Port"
Checked="btnOpenPort_Checked" Unchecked="btnOpenPort_Unchecked"
IsChecked="{Binding Path=PortViewModel.PortIsOpen, Mode=OneWay}"
Canvas.Left="75" Canvas.Top="80" Height="25" Width="100"/>
But this is not what I aim to do. Because in this case, I would have to set properties in the code behind for the Checked and Unchecked event.
Instead, I would like to call a Command (ICommand) in my ViewModel once the Checked or Unchecked event gets fired so that I don't need any code-behind for my toggle button.
Is there a way to bind a command directly for these two events in XAML?
Similar to the command property of the "standard" button control in WPF?
EDIT
This is how it works with regards to #har07 hint:
1: Added references if you dont have it yet:
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:ei="clr-namespace:Microsoft.Expression.Interactivity.Core;assembly=Microsoft.Expression.Interactions"
2: Implemented Interaction.Triggers for Checked and Unchecked events:
<ToggleButton
Name="btnOpenPort" Style="{StaticResource myOnOffBtnStyle}" Content="Open Port"
IsChecked="{Binding Path=PortViewModel.PortIsOpen, Mode=OneWay}"
Canvas.Left="75" Canvas.Top="80" Height="25" Width="100">
<i:Interaction.Triggers>
<i:EventTrigger EventName="Checked">
<i:InvokeCommandAction Command="{Binding Path=PortViewModel.OpenPort}"/>
</i:EventTrigger>
<i:EventTrigger EventName="Unchecked">
<i:InvokeCommandAction Command="{Binding Path=PortViewModel.ClosePort}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</ToggleButton>
With this solution, I don't have to change a single line of code in my ViewModel or my code behind.
I can just call my ICommand as I would do it with a standard button following MVVM pattern.

Answer 1

you may not be able to bind two commands for each checked and unchecked directly however you can still bind a command, which will be invoked for both. you also have option for attached behaviors if you need different command for both events.
<ToggleButton Command="{Binding MyCommand}"/>
in the vm
public ICommand MyCommand { get; private set; }
you will need to initialize it accordingly
and to determine the current state you may have a condition on the bonded property PortIsOpen
void Execute(object state)
{
if(PortIsOpen)
{
//checked
}
else
{
//unchecked
}
}
or perhaps you may pass it as a parameter too
eg
<ToggleButton Command="{Binding MyCommand}"
CommandParameter="{Binding IsChecked,RelativeSource={RelativeSource Self}}"/>
and use it as
void Execute(object state)
{
if((bool)state)
{
//checked
}
else
{
//unchecked
}
}

Answer 2

Maybe we can use EventTriggers
<ToggleButton>
<i:Interaction.Triggers>
<i:EventTrigger EventName="Checked">
<i:InvokeCommandAction Command="{Binding Path=CheckedCommand}"/>
</i:EventTrigger>
<i:EventTrigger EventName="Unchecked">
<i:InvokeCommandAction Command="{Binding Path=UncheckedCommand}"/>
</i:EventTrigger>
</i:Interaction.Triggers>
</ToggleButton>
to use Triggers we have to reference System.Windows.Interactivity
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"

Answer 3

You can put the logic to handle checked/unchecked event in the setter of PortIsOpen property :
private bool _portIsOpen;
public bool PortIsOpen
{
get { return _portIsOpen; }
set
{
if(value) HandleCheckedEvent();
else HandleUnCheckedEvent();
....
}
}
Or you can use Ineraction.Triggers extension to bind event to commmand :
WPF Binding UI events to commands in ViewModel

Answer 4

<ToggleButton Name="btnOpenPort" Style="{StaticResource myOnOffBtnStyle}" Content="Open Port"
Checked="{Binding ICommand}" Unchecked="{Binding ICommand}"
IsChecked="{Binding Path=PortViewModel.PortIsOpen, Mode=OneWay}"
Canvas.Left="75" Canvas.Top="80" Height="25" Width="100"/>
Replace ICommand with your ICommand property name.