What is ApplicationFrameHost?

博麟吴 46

I found that there are actually two parts of a UWP application which is called ApplicationFrameHost.exe and its 'real' exe.

So why UWP apps need a 'host'?
Also, I've found that UWP cannot run without explorer.exe. After I stop the Explorer, I can't start a new app, and those opened app will have some incorrect behaviours when I try to resize or close them.

Nico Zhu (Shanghai Wicresoft Co,.Ltd.) 12,851 Reputation points

2022-06-23T08:33:07.13+00:00

Could you tell why you want to detect ApplicationFrameHost, what's you really want to do? Does ApplicationFrameHost cause the problem in current environment?
博麟吴 46 Reputation points

2022-06-23T08:48:57.403+00:00

I'm just wondering that what the relationship between ApplicationFrameHost and the app being hosted., because I find all UWP apps can't run without ApplicationFrameHost.exe.
BTW, WinUI 3 can host WinRT controls without ApplicationFrameHost, what cause the difference?
Nico Zhu (Shanghai Wicresoft Co,.Ltd.) 12,851 Reputation points

2022-06-23T08:55:32.11+00:00

Actually, WinUI3 project is not UWP, it is desktop app with UWP ui design. I have to say there is no document to explain what's the **ApplicationFrameHost **, but i think it is frame container that use to manage UWP' frame render. I will disscuss with team to get more info about this, If I get any response, I will update below.
博麟吴 46 Reputation points

2022-06-23T09:08:19.427+00:00

Thanks for your reply.
I hope that Microsoft can make UWP developing more clear. Or, just to say that UWP has been the past and our future is WinUI 3, we will give the developers the same experience as UWP did (Desktop/Xbox/Hololens/Mobile (if MSFT wants) and something like CoreWindow where I can just copy my UWP code without any change).
Nico Zhu (Shanghai Wicresoft Co,.Ltd.) 12,851 Reputation points

2022-06-23T09:37:30.273+00:00

WinUI3 is different with UWP, and WinUI3 is more like general desktop app with uwp ui design, you can't copy the code directly, and it has splited two different namesapces, one is Windows the other is Microsoft. We suggest you refer Migrate from UWP to the Windows App SDK document to migrate your code if you want to use WInUI3's specific feature.