error dialog when no token

Turbulence.Core/ViewModels/MainWindowViewModel.cs

@@ -25,6 +25,8 @@ public partial class MainWindowViewModel : ViewModelBase,
 
     private readonly IPlatformClient _client = Ioc.Default.GetService<IPlatformClient>()!;
 
+    public event EventHandler<string>? ErrorEvent;
+
     [ObservableProperty]
     private bool _searchOpen = false;
 
@@ -51,7 +53,14 @@ public void Connect()
             return;
 
         // Get token
-        var token = new ConfigurationManager().AddUserSecrets<MainWindowViewModel>().Build()["token"]! ?? throw new Exception("No token set"); // TODO: use other storage
+        var token = new ConfigurationManager().AddUserSecrets<MainWindowViewModel>().Build()["token"]; //TODO: use other storage
+        if (token == null)
+        {
+            ErrorEvent?.Invoke(this, "No Token set.");
+            Messenger.Send(new SetStatusMsg("Error"));
+            return;
+        }
+
         Task.Run(() => _client.Start(token));
         Messenger.Send(new SetStatusMsg("Connecting..."));
     }

Turbulence.Desktop/Dialogs/OkWindow.axaml

@@ -0,0 +1,23 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:dialogs="clr-namespace:Turbulence.Desktop.Dialogs"
+        mc:Ignorable="d" d:DesignWidth="250" d:DesignHeight="150"
+        MaxWidth="250" MaxHeight="150"
+        WindowStartupLocation="CenterOwner"
+        x:Class="Turbulence.Desktop.Dialogs.OkWindow"
+        x:DataType="dialogs:OkWindow"
+        Title="Info">
+    <Grid Background="#313338">
+        <Grid.RowDefinitions>
+            <RowDefinition Height="30" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="30" />
+            <RowDefinition Height="Auto" />
+            <RowDefinition Height="15" />
+        </Grid.RowDefinitions>
+        <TextBlock Grid.Row="1" HorizontalAlignment="Center" Text="{Binding Prompt}" TextWrapping="Wrap">Prompt</TextBlock>
+        <Button Grid.Row="3" Name="abort" HorizontalAlignment="Center" VerticalAlignment="Center" Width="100" Click="OnClick">OK</Button>
+    </Grid>
+</Window>

Turbulence.Desktop/Dialogs/OkWindow.axaml.cs

@@ -0,0 +1,45 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using Avalonia.Markup.Xaml;
+using System;
+using System.ComponentModel;
+using System.Runtime.CompilerServices;
+
+namespace Turbulence.Desktop.Dialogs;
+
+public partial class OkWindow : Window, INotifyPropertyChanged
+{
+    // Needed to notify the view that a property has changed
+    public event PropertyChangedEventHandler? PropertyChanged;
+
+    // The prompt shown at the top
+    private string? prompt;
+
+    public string Prompt
+    {
+        get => prompt ?? "";
+
+        set
+        {
+            if (value != prompt)
+            {
+                prompt = value;
+                NotifyPropertyChanged();
+            }
+        }
+    }
+
+    private void NotifyPropertyChanged([CallerMemberName] string propertyName = "")
+    {
+        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+    }
+
+    public OkWindow()
+    {
+        InitializeComponent();
+        DataContext = this;
+    }
+
+    private void OnClick(object sender, RoutedEventArgs e) => Close();
+}

Turbulence.Desktop/MainWindow.axaml.cs

@@ -4,6 +4,7 @@
 using Avalonia.Input;
 using Avalonia.Interactivity;
 using Turbulence.Core.ViewModels;
+using Turbulence.Desktop.Dialogs;
 
 namespace Turbulence.Desktop;
 
@@ -16,6 +17,17 @@ public MainWindow()
     {
         InitializeComponent();
         _vm = (MainWindowViewModel)DataContext!;
+        _vm.ErrorEvent += OnErrorEvent;
+    }
+
+    private async void OnErrorEvent(object? sender, string e)
+    {
+        OkWindow errorDialog = new()
+        {
+            Title = "Error",
+            Prompt = e
+        };
+        await errorDialog.ShowDialog(this);
     }
 
     // Menu Item Handlers //TODO: move them into the menu bar view + use it??