Why mouse event is not fired when inside listview? - wpf

Question

I am using System.Windows.Interactivity and i have to display a Message on mouse enter event.
The problem is the same event is called when done outside the ListView, But it gets not called when inside the ListView.
I tried doing so using mvvm approach:
<Grid>
<StackPanel Grid.Row="1" Grid.Column="1" Name="events1">
//This Event works outside the ListView but not inside ListView
<Rectangle Fill="Yellow" Stroke="Black" Width="100" Height="30">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseEnter">
<i:InvokeCommandAction Command="{Binding SomeCommand}" />
</i:EventTrigger>
</i:Interaction.Triggers>
</Rectangle>
<ListView BorderBrush="#FF1D93E4" BorderThickness="4" Behaviour:GridViewColumnResize.Enabled="True" ScrollViewer.VerticalScrollBarVisibility="Auto" SelectedItem="{Binding SelectedItem ,Mode=TwoWay}" ItemsSource="{Binding Ur1r2_Obj}" HorizontalContentAlignment="Stretch">
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
</Style>
</ListView.ItemContainerStyle>
<ListView.View>
<GridView>
<GridViewColumn Header="State" Behaviour:GridViewColumnResize.Width="*">
<GridViewColumn.CellTemplate>
<DataTemplate>
<Grid Background="{Binding Converter={StaticResource colorToBrushConverter}}">
//The event do not work here
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseEnter">
<i:InvokeCommandAction Command="{Binding SomeCommand}" />
</i:EventTrigger>
</i:Interaction.Triggers>
<Button Margin="35,0,0,0" HorizontalAlignment="Center" Content="{Binding Path=Etat, Mode=OneWay}" Background="{Binding Converter={StaticResource colorToBrushConverter}}" />
</Grid>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
</StackPanel>
</Grid>
In view Model
private ICommand someCommand;
public ICommand SomeCommand
{
get
{
//return plotButton;
return someCommand ?? (someCommand = new CommandHandler(() => MyAction2(), _canExecute));
}
set
{
someCommand = value;
OnPropertyChanged("SomeCommand");
}
}
private void MyAction2() //Messsage is popuped on Moseenter event when i try to hover mouse over rectangle outside the listview , But not get called when inside the Listview
{
MessageBox.Show("Yeah Called");
}
Why it event is not called from inside the ListView. How to make it call ?

Answer 1

If you are trying to invoke the same command (SomeCommand) you should specify a RelativeSource of the Binding:
<Grid Background="{Binding Converter={StaticResource colorToBrushConverter}}">
<i:Interaction.Triggers>
<i:EventTrigger EventName="MouseEnter">
<i:InvokeCommandAction Command="{Binding DataContext.SomeCommand,
RelativeSource={RelativeSource AncestorType=ListView}}" />
</i:EventTrigger>
</i:Interaction.Triggers>
<Button Margin="35,0,0,0" HorizontalAlignment="Center" Content="{Binding Path=Etat, Mode=OneWay}" Background="{Binding Converter={StaticResource colorToBrushConverter}}" />
</Grid>
The DataContext of an item in the ListView is an object in your "Ur1r2_Obj" ItemsSource whereas the DataContext of the Rectangle is your view model. That's why the binding fails in your CellTemplate.