Xamarin reuse viewmodel on user control - xamarin

Question

In my MainPage.xaml, which is a ContentPage, I have two user controls.
Both of which are ContentView and are loaded like this:
<local:MyView2 HorizontalOptions="Start"
VerticalOptions="Fill">
<local:MyView2.BindingContext>
<viewmodels:NavbarViewModel />
</local:MyView2.BindingContext>
<local:MyView2.Triggers>
<DataTrigger TargetType="{x:Type local:MyView2}" Binding="{Binding IsPresented}" Value="True">
<DataTrigger.EnterActions>
<local:MenuTrigger IsPresented="True"/>
</DataTrigger.EnterActions>
<DataTrigger.ExitActions>
<local:MenuTrigger IsPresented="False" />
</DataTrigger.ExitActions>
</DataTrigger>
</local:MyView2.Triggers>
</local:MyView2>
// omitted myview1, they are basically the same
My MainPage has a different viewmodel than MyView1 and 2 which are the contentviews.
But the bindingcontext I have said is not accessible from inside the contentview:
<ContentView xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="Universal_ONE.MyView1"
x:Name="MyView1Name">
<Frame BackgroundColor="#385C6C"
Padding="0,0,0,0">
<ImageButton Source="outline_menu_white_24.png"
Command="{Binding Source={x:Reference MyView1Name}, Path=PresentMenu}}"
WidthRequest="24"
HeightRequest="24"
Margin="15,0,0,0"
BackgroundColor="Transparent"
HorizontalOptions="StartAndExpand" />
</Frame>
</ContentView>
I also tried it like this:
<ContentView xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="Universal_ONE.MyView1">
<Frame BackgroundColor="#385C6C"
Padding="0,0,0,0">
<ImageButton Source="outline_menu_white_24.png"
Command="{Binding PresentMenu}"
WidthRequest="24"
HeightRequest="24"
Margin="15,0,0,0"
BackgroundColor="Transparent"
HorizontalOptions="StartAndExpand" />
</Frame>
</ContentView>
The error I get on the PresentMenu: No DataContext found for binding PresentMenu
How do I access the bindingcontext inside my contentview?
If it was not clear already, the contentviews are in a seperate file.
EDIT:
NavbarViewModel:
public class NavbarViewModel : INotifyPropertyChanged
{
public NavbarViewModel()
{
isPresented = false;
PresentMenu = new Command(() => IsPresented = !IsPresented);
}
bool isPresented;
public bool IsPresented
{
get => isPresented;
set
{
isPresented = value;
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(IsPresented)));
}
}
public event PropertyChangedEventHandler PropertyChanged;
public ICommand PresentMenu { private set; get; }
}
EDIT 2:
I have added:
x:DataType="viewmodels:NavbarViewModel
To both contentviews, this removes the error that it has no DataContext. However, the binding still does not work.
Working solution:
I have now added the viewmodel as a staticresource in app.xaml and just reuse that everywhere including in the user controls. I hope to look at this again at some point in the future.