MVVM Model doubts

Question

I'm a mvvm beginner, I'm trying to port an old app from winform. basically it have 3 docked usercontrol where a log is displayed in as a 3d chart in one control, as 2d chart pie in the second and as a list of points in the last. When the user start the app an openfiledialog appear to load the binary log file, that are loaded into an array.
Now moving in mvvm, I managed to use a dock control and work fine;
1- I'm struggle to understand how to load the file trough the openfiledialog from the shell, and made it available for the 3 viewmodels (of the usercontrols).
2-I need also to save some user setting like background color, etc. In winform I used mysetting, and worked fine. Now using WPF .NET 5.0, seem to be deprecated right? Is there a simple alternative, easy to implement without mess up the mvvm that I'm slowly building?
I'm targeting .NET 5.0, and using Sylet MVVM Framework(it's similar to CaliburnMicro).
Any advice?

Answer 1

Hi Ajeje,
try following demo with 2 UserControls and 3 ViewModels; ViewModel0 - main ViewModel, ViewModel1 - for UserControl1, ViewModel2 - for UserControl2.

XAML Main Window:

<UserControl x:Class="Window096UC2"  
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"  
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"   
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"   
             xmlns:local="clr-namespace:WpfControlLibrary1.WpfApp096"  
             mc:Ignorable="d"   
             d:DesignHeight="450" d:DesignWidth="800">  
  <UserControl.Resources>  
    <local:ViewModel2 x:Key="vm2"/>  
  </UserControl.Resources>  
  <Border BorderBrush="Green" BorderThickness="2">  
    <StackPanel>  
      <Label Content="UserControl 2"/>  
      <TextBox Text="{Binding Text0, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
      <TextBox Text="{Binding Text2, Source={StaticResource vm2}, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
      <TextBox Text="{Binding Text2, Source={StaticResource vm2}, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
    </StackPanel>  
  </Border>  
</UserControl>  

XAML UserControl1:

<UserControl x:Class="Window096UC1"  
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"  
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"   
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"   
             xmlns:local="clr-namespace:WpfControlLibrary1.WpfApp096"  
             mc:Ignorable="d"   
             d:DesignHeight="450" d:DesignWidth="800">  
  <UserControl.Resources>  
    <local:ViewModel1 x:Key="vm1"/>  
  </UserControl.Resources>  
  <Border BorderBrush="Red" BorderThickness="2">  
    <StackPanel>  
      <Label Content="UserControl 1"/>  
      <TextBox Text="{Binding Text0, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
      <TextBox Text="{Binding Text1, Source={StaticResource vm1}, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
      <TextBox Text="{Binding Text1, Source={StaticResource vm1}, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
    </StackPanel>  
  </Border>  
</UserControl>  

XAML UserControl2:

<UserControl x:Class="Window096UC2"  
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"  
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"   
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"   
             xmlns:local="clr-namespace:WpfControlLibrary1.WpfApp096"  
             mc:Ignorable="d"   
             d:DesignHeight="450" d:DesignWidth="800">  
  <UserControl.Resources>  
    <local:ViewModel2 x:Key="vm2"/>  
  </UserControl.Resources>  
  <Border BorderBrush="Green" BorderThickness="2">  
    <StackPanel>  
      <Label Content="UserControl 2"/>  
      <TextBox Text="{Binding Text0, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
      <TextBox Text="{Binding Text2, Source={StaticResource vm2}, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
      <TextBox Text="{Binding Text2, Source={StaticResource vm2}, UpdateSourceTrigger=PropertyChanged}"  
               Margin="5"/>  
    </StackPanel>  
  </Border>  
</UserControl>  

ViewModels:

Imports System.ComponentModel  
Imports System.Runtime.CompilerServices  
  
Namespace WpfApp096  
  
  Public Class ViewModel0  
    Inherits ViewModelBase  
    Private _text0 As String  
    Public Property Text0 As String  
      Get  
        Return Me._text0  
      End Get  
      Set(value As String)  
        Me._text0 = value  
        OnPropertyChanged()  
      End Set  
    End Property  
  End Class  
  
  Public Class ViewModel1  
    Inherits ViewModelBase  
    Private _text1 As String  
    Public Property Text1 As String  
      Get  
        Return Me._text1  
      End Get  
      Set(value As String)  
        Me._text1 = value  
        OnPropertyChanged()  
      End Set  
    End Property  
  End Class  
  
  Public Class ViewModel2  
    Inherits ViewModelBase  
    Private _text2 As String  
    Public Property Text2 As String  
      Get  
        Return Me._text2  
      End Get  
      Set(value As String)  
        Me._text2 = value  
        OnPropertyChanged()  
      End Set  
    End Property  
  End Class  
  
  Public Class ViewModelBase  
      Implements INotifyPropertyChanged  
      Public Event PropertyChanged As PropertyChangedEventHandler Implements INotifyPropertyChanged.PropertyChanged  
    Protected Sub OnPropertyChanged(<CallerMemberName> Optional propName As String = "")  
      RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(propName))  
    End Sub  
  End Class  
  
End Namespace  

Result:

Answer 2

Hi Ajeje,

1- I'm struggle to understand how to load the file trough the openfiledialog from the shell, and made it available for the 3 viewmodels (of the usercontrols).

You can use the same ViewModel instance in each UserControl.

2-I need also to save some user setting like background color, etc. In winform I used mysetting, and worked fine. Now using WPF .NET 5.0, seem to be deprecated right?

You write your own Setting class. For properties in this setting class you can use static members. To save settings you can use serializing.