Prevent disconnected display from merging windows into the active one - windows

I've got a personal laptop (running Windows 10) which I use at work where I connect it to an external display using extended display mode. I keep all my personal icons and windows on my laptop display and store all the work-related windows on the external display. Whenever I unplug it, all the windows and icons from that display are merged into my laptop screen. I want to programmatically prevent changing anything on my primary screen when the secondary is disconnected. I'm currently writing a utility app for a variety of small productivity improving features and would like to add such feature in it. I can think of two ways to achieve this:
by tricking the system to think that the external display hasn't been
disconnected;
or take all the opened windows and icons on disconnected screen and put them on separate virtual desktop.
I was looking into Windows GDI Device Context Functions but haven't found anything about display connection/disconnection events. How can I detect display disconnection (and get that display's opened windows and icons)? Anything that can be done using C#, C++ or PowerShell scripts would be much appreciated!

Related

Windows Containers - Is it possible to interact with desktop apps running in a container using the Desktop Sharing API?

I understand that desktop/GUI apps are not supported in Windows containers. They do run but there's no built-in way to interact with them. I had the following idea - maybe I could use the Desktop Sharing API (https://learn.microsoft.com/en-us/windows/win32/api/_rdp/) for this purpose, the idea is to run a desktop app, then run a sharing program that uses the Desktop Sharing API, and connect to it using a Desktop Sharing API viewing program from the host.
I had to do some recap about window stations and desktops, and I noticed that when starting the container with cmd in interactive mode, I'm logged with ContainerAdministrator as a service (logon type 5). I tried running some WinAPI functions that deal with desktops and winstation and got some access denied results, so I switched to running cmd as system.
The window station of the cmd process (and other child processes) is not the interactive WinSta0, but instead some other service window station, which makes sense since I'm logged on as a service, and I figured that I can't use this window station, so I used a little program I wrote to run notepad in Winsta0 in the Default desktop. Afterwards I ran another program that enumerates the windows on WinSta0\Default, and the notepad window does get enumerated and I also get it's title, so it's running somewhere.
So now I tried running the desktop sharing API program (also on WinSta0\Default). It runs and I can connect from the host, but I only get a black screen without anything on it. I also tried running a program that takes a screenshot of the windows but I get an empty bitmap.
So I thought maybe the Default desktop is not the active desktop, and by using the OpenInputDesktop function I could confirm it - the current desktop was the Winlogon desktop, so I used the SwitchDesktop function to switch to the Default desktop (I used OpenInputDesktop again to verify that it actually worked).
Unfortunately, this didn't change anything, I still get an empty screen and empty bitmaps.
I know that containers are built for micro services and are not supposed to run GUI apps and so, but still - is there a way to make this work? Or any ideas of what else I can check? Alternatively, if you know that it can't work - I would also be happy to hear a good technical explanation of why it doesn't work.

Windows Forms text grows too big when run on another PC

I've got a VB.Net Windows Form application containing several controls (labels, groupboxes, comboboxes, etc.) This application is deployed to several PCs running Windows 10. There are also Win10 tablets connecting to these PCs via Remote Desktop. The issue is that the text on the form sometimes gets resized and overlaps onto other controls when viewed on the tablet. In other words, the text becomes too big.
I thought this was only happening when using Remote Desktop but today I saw it happen on a PC too. This is the first time this has happened. One difference is that the PC was re-imaged in the field instead of being brought back to the office first. The monitors used between the two locations are different, and I'm suspecting this has something to do with it. I know there are DPI and resolution factors to consider but don't fully understand how to rectify them in this case, or if they're even applicable.
Here's how it looks as designed and running on my dev PC:
And here's how it looks when running on the production PC (sorry for the grainy image):
Of note is that some text doesn't appear to get oversized, for example the "Currently: 6 ft/min". All fonts are Microsoft Sans Serif.
Suggestions?
The answer provided here worked for me by changing the compatibility settings for the executable. Another method is provided here but I haven't had a chance to test it yet.

How to put monitor on standby and not let it wake up

I have 3 monitors, but I don't need them all turned on all the time. I can just shut them down with power button, but I want to use their standby mode, like Windows does when we let PC idle for a while - it shuts down monitors, HDD, etc.
But of course, I wanna keep using PC and let just that monitor on standby. Others must remain on and that one doesn't wake up even with me using PC.
Is it possible to do that? It would be great to have a shortcut like Winkey+1, 2, 3 etc to shut down and wake up each monitor.
An existing app with this feature is not likely to exist, but is there a Windows API function that can control monitor state, for each monitor in a MultiMonitor system?
The display control panel applet calls SetDisplayConfig to start or stop forced projection on a particular target
You can probably use MS Detours or some other API hooking tool to inspect the usage pattern of the API while using the applet to adjust display settings.
You'll want to try Display Fusion. You should be able to do what you're asking for using Monitor configurations.
I know I'm late on this but use DDC to control your display. You can easily create hotkeys that send a command via DDC to the display to turn-off. This would be equivalent to turning off the display using the button. Works like a charm for me. The only trick is that DDC command specs vary across monitor manufacturers but its not hard to find the right codes to send with the help of google.
Ready made tools also exist for this; search for anything that is related to DDC or EDID and you should find.
Be aware though that this does not remove the display from Windows which means that apps may find their way onto displays that are off and you will be looking for them.

How to detect if Windows 8 is showing desktop

In a Windows desktop application written in C# and running on Windows 8 how can I detect if Windows 8 is in desktop mode (i.e. showing the Desktop rather than the modern UI)?
Although it's in C++, the Start Screen Visibility Sample should be a good starting point for you. It uses COM objects to get the state of all monitors on the system that are either displaying Windows Store Apps or the Start Screen, and illustrates how to receive notifications when the state of a monitor changes or when the visibility of the Start screen changes.

Is there an analogue of Windows Phone 'User Idle Detection' in Windows 8?

I've used the following code on Windows Phone 7 and 8 to disable user idle detection when my App is displaying data to the user and they are unlikely to interact with the screen e.g. A recipe App where the screen needs to stay on:
http://msdn.microsoft.com/en-us/library/microsoft.phone.shell.phoneapplicationservice.useridledetectionmode(v=vs.92).aspx
Does anyone know if there is an analogue of this available for Windows 8 applications? My tablet app has the same requirement to disable the screen turning off. I haven't managed to find anything :-(
Many thanks,
Jon
You should use the DisplayRequest class, specifically DisplayRequest.RequestActive for this purpose. You must also remember to call DisplayRequest.RequestRelease once you are done to allow the display to sleep, for example, if you are not viewing a recipe, or you are in a menu screen, etc.

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