Here's the code

<Window x:Class="WpfTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        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:local="clr-namespace:BobuxNotifierWpfTest"
        mc:Ignorable="d"
        Title="test app" Height="450" Width="800"
        Background="#fff0f6">
    <Grid Width="390" HorizontalAlignment="Left" Margin="10,10,0,10" Background="#ffe8f2">
        <Grid.RowDefinitions>
            <RowDefinition Height="400*"/>
            <RowDefinition Height="30*"/>
        </Grid.RowDefinitions>
        <Label FontSize="35" FontWeight="DemiBold" FontFamily="Fonts\Halyard Text Regular" Margin="10,0,10,10">
            heading
        </Label>
        <TextBlock FontSize="18" FontFamily="Fonts\Halyard Text Regular" FontWeight="DemiBold" Foreground="#633247" Margin="15,65,0,0" TextWrapping="WrapWithOverflow">
            <Label>first body line</Label>
            <Label>second body line</Label>
            <Label FontSize="12" Margin="0,20,0,0">footer</Label>
        </TextBlock>
    </Grid>
</Window>

this code didn't give me any errors but when I run it all I got was

========== Build: 1 succeeded, 0 failed, 0 up-to-date, 0 skipped ==========

I also didn't do anything to the Main() class or the xaml.cs file

any help lol

CodePudding user response：

Application is usually one of the most important classes in your WPF project, not useless.

Encapsulates a Windows Presentation Foundation application. [...]

You can implement an Application using markup, markup and code-behind, or code. If Applicationis implemented with markup, whether markup or markup and code-behind, the markup file must be configured as an Microsoft build engine (MSBuild) ApplicationDefinition item.

You have to tell WPF which window should be shown on startup using StartupUri.

<Application x:Class="WpfTest.MainWindow"
             ...
             StartupUri="MainWindow.xaml">

Another way is adding a Startup event handler and creating your window there.

<Application WpfTest.MainWindow""
             ...
             Startup="OnStartup">

public partial class App : Application
{
   private void OnStartup(object sender, StartupEventArgs e)
   {
      new MainWindow().Show();
   }
}

That being said, it is possible to run a WPF standalone application without an Application instance.

A standalone application does not require an Application object; it is possible to implement a custom static entry point method (Main) that opens a window without creating an instance of Application.

However, it is in all likelihood not what you want to do since the application object provides services like an application-wide resource dictionary to name just one with a big impact.

Application implements the singleton pattern to provide shared access to its window, property, and resource scope services. [...]

• Application Lifetime: Activated, Current, Deactivated, DispatcherUnhandledException, Exit, Run, SessionEnding, Shutdown, ShutdownMode, Startup.

• Application-Scope Window, Property, and Resource Management: FindResource, GetContentStream, GetResourceStream, LoadComponent, MainWindow, Properties, Resources, StartupUri, Windows.

• Command-Line Parameter and Exit Code Processing: Application.Startup, Application.Exit, Application.Shutdown.

• Navigation: FragmentNavigation, LoadCompleted, Navigated, Navigating, NavigationProgress, NavigationStopped, NavigationFailed, SetCookie, GetCookie.