Official Microsoft Sample

This sample shows how to use the GetContentRects API to take advantage of dual-screen devices and to provide the best experience on multi-display PCs. The sample uses a poly-filled version of the API based on EnumDisplayMonitors so you can test it on existing Desktop PCs before Windows 10X is released.

File/folder	Description
`src`	Sample source code.
`.gitignore`	Define what to ignore at commit time.
`CHANGELOG.md`	List of changes to the sample.
`CONTRIBUTING.md`	Guidelines for contributing to the sample.
`README.md`	This README file.
`LICENSE`	The license for the sample.

Prerequisites

This requires Visual Studio 2019 and a recent version of the Windows 10 Insider SDK. It does not require a Windows 10X device or the Windows 10X emulator, but they can be used as well.

Setup

Clone the sample and then build the DualScreenWin32 project. There is also an MSIX project for deploying the application to other devices (including the Windows 10X emulator). MSIX is the recommended way of packaging applications for Windows 10.

Running the sample

By default the application draws a cyan rectangle with some information about the window's client area.

If you have the Windows 10X emulator (or a dual-screen device), you can snap the app across both screens to see the app reconfigure itself to draw one screen in cyan and the other in yellow.

If you have a Desktop PC with multiple monitors, you can simply move the window between two monitors to get the same effect as a dual-screen device. You might choose to update your existing Win32 apps even if you don't specifically intend to target Windows 10X since you can improve the experience for your existing Desktop users with multiple monitors.

If you have a single-screen Desktop, you can use the Tools -> Toggle modes menu item to emulate different dual-screen configurations. Note that even on a single-screen device, if you move the window partially off-screen, you will see the application responds and ensures the content remains on-screen.

Key concepts

The key concept here is the use of the GetContentRects API to query the OS for the available ares where the application can draw. The app can still render content across the entire client area (spanning the gap on a dual-screen device, or spanning monitors on a Desktop), but being aware of the distinct content regions will enable you to optimize the experience.

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.opensource.microsoft.com.

When you submit a pull request, a CLA bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., status check, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.