WinUI3透明背景 WinUI3 Transparent Background Cpp/WinRT Implementation

Original Readme

WinUI3的窗口背景有两层，一层是Win32窗口的背景，一层是DesktopWindowXamlSource中Visual的背景。

去除Win32窗口背景的方式有很多，这里参考了castorix/WinUI3_Transparent的方案

去除Visual背景的方式，是通过ICompositionSupportsSystemBackdrop接口设置一个透明画刷，此时框架会自动移除黑底。

Name		Name	Last commit message	Last commit date
Latest commit History 3 Commits
Assets		Assets
.gitignore		.gitignore
App.idl		App.idl
App.xaml		App.xaml
App.xaml.cpp		App.xaml.cpp
App.xaml.h		App.xaml.h
MainWindow.idl		MainWindow.idl
MainWindow.xaml		MainWindow.xaml
MainWindow.xaml.cpp		MainWindow.xaml.cpp
MainWindow.xaml.h		MainWindow.xaml.h
Package.appxmanifest		Package.appxmanifest
SystemBackdropHelper.hpp		SystemBackdropHelper.hpp
WinUI3-TransparentBackground-CppWinRT.sln		WinUI3-TransparentBackground-CppWinRT.sln
WinUI3-TransparentBackground-CppWinRT.vcxproj		WinUI3-TransparentBackground-CppWinRT.vcxproj
WinUI3-TransparentBackground-CppWinRT.vcxproj.filters		WinUI3-TransparentBackground-CppWinRT.vcxproj.filters
WinUI3-TransparentBackground-CppWinRT.vcxproj.user		WinUI3-TransparentBackground-CppWinRT.vcxproj.user
app.manifest		app.manifest
packages.config		packages.config
pch.cpp		pch.cpp
pch.h		pch.h
readme.md		readme.md
readme.txt		readme.txt