Maui -- How to make the background color transparent?

Question

I'm trying to write a program that would be used as an overlay on top of another program. I want the text, buttons, and border to be solid, and the background to be transparent.

<VerticalStackLayout Spacing="25" Padding="30" BackgroundColor="Transparent" IsVisible="True" Opacity="1">

That works for one of the layers, but it appears that there are multiple layers.

Here it mentions changing the ContentPage, which I tried, and it appears not to be working.

<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
         xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
         x:Class="NameSpace.MainPage"
         xmlns:local="clr-namespace:NameSpace"    
         BackgroundColor="Transparent">

I also tried:

<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
         xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
         x:Class="NameSpace.MainPage"
         xmlns:local="clr-namespace:NameSpace.Core.Views.CustomControls"    
         BackgroundColor="Transparent">

I changed the Shell to include a Transparent background color, which didn't help.

<Shell
x:Class="NameSpace.AppShell"
xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:local="clr-namespace:NameSpace"
Shell.FlyoutBehavior="Disabled"
BackgroundColor="Transparent">

It appears that nothing changed when changing either the ContentPage or the Shell.

None of those seem to change the background color behind the VerticalStackLayout. Any ideas?

Answer 1

I know this is old question but maybe can help another you can use hex alpha for colors.

You need to use this alpha codes with color code Alpha + Color, for example #80FFFFFF

• 100% — FF
• 99% — FC
• 98% — FA
• 97% — F7
• 96% — F5
• 95% — F2
• 94% — F0
• 93% — ED
• 92% — EB
• 91% — E8
• 90% — E6
• 89% — E3
• 88% — E0
• 87% — DE
• 86% — DB
• 85% — D9
• 84% — D6
• 83% — D4
• 82% — D1
• 81% — CF
• 80% — CC
• 79% — C9
• 78% — C7
• 77% — C4
• 76% — C2
• 75% — BF
• 74% — BD
• 73% — BA
• 72% — B8
• 71% — B5
• 70% — B3
• 69% — B0
• 68% — AD
• 67% — AB
• 66% — A8
• 65% — A6
• 64% — A3
• 63% — A1
• 62% — 9E
• 61% — 9C
• 60% — 99
• 59% — 96
• 58% — 94
• 57% — 91
• 56% — 8F
• 55% — 8C
• 54% — 8A
• 53% — 87
• 52% — 85
• 51% — 82
• 50% — 80
• 49% — 7D
• 48% — 7A
• 47% — 78
• 46% — 75
• 45% — 73
• 44% — 70
• 43% — 6E
• 42% — 6B
• 41% — 69
• 40% — 66
• 39% — 63
• 38% — 61
• 37% — 5E
• 36% — 5C
• 35% — 59
• 34% — 57
• 33% — 54
• 32% — 52
• 31% — 4F
• 30% — 4D
• 29% — 4A
• 28% — 47
• 27% — 45
• 26% — 42
• 25% — 40
• 24% — 3D
• 23% — 3B
• 22% — 38
• 21% — 36
• 20% — 33
• 19% — 30
• 18% — 2E
• 17% — 2B
• 16% — 29
• 15% — 26
• 14% — 24
• 13% — 21
• 12% — 1F
• 11% — 1C
• 10% — 1A
• 9% — 17
• 8% — 14
• 7% — 12
• 6% — 0F
• 5% — 0D
• 4% — 0A
• 3% — 08
• 2% — 05
• 1% — 03
• 0% — 00

Answer 2

Fully transparent windows aren't currently supported. MAUI runs on WinUI for Windows apps, and WinUI doesn't yet support transparent windows. There are open feature requests for it at:

• Proposal: Borderless transparent window background support in apps using WinUI #1247
• In WinUI 3, is it possible to create a transparent Xaml Island overlay on top of parent hwnd? #2956