Answer by Liyun Zhang - MSFT for MAUI landscape mode grid issues

I copied your code and just add Grid.RowSpan="3" for the grid. And then I get the effect you want without LayoutChanged and Appearing.

The full xaml:

<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"             x:Class="MauiApp7.MainPage" Shell.NavBarIsVisible="False"><Grid BackgroundColor="Pink"><Grid.ColumnDefinitions><ColumnDefinition Width="80" /><ColumnDefinition Width="80"/><ColumnDefinition Width="80"/><ColumnDefinition Width="80"/><ColumnDefinition Width="80"/><ColumnDefinition Width="80"/><ColumnDefinition Width="*"/></Grid.ColumnDefinitions><Grid.RowDefinitions><RowDefinition Height="80"/><RowDefinition Height="80"/><RowDefinition Height="80"/></Grid.RowDefinitions><Grid x:Name="gridLayoutBox"               BackgroundColor="Blue"                IsClippedToBounds="True"               Grid.ColumnSpan="6"               Grid.RowSpan="3" ></Grid></Grid></ContentPage>

And the result image:

In addition, if you want to force landscape, you can all the following code in the Page's OnHandlerChanged method or OnAppearing method.

#if ANDROIDMicrosoft.Maui.ApplicationModel.Platform.CurrentActivity.RequestedOrientation = Android.Content.PM.ScreenOrientation.Landscape;#endif

And in the Portrait mode, the blue grid will be cut off beacause its width is bigger than the screen's width.