Is it possible to detect Windows on screen keyboard? - windows

Context: our desktop application is used predominantly by users with significant access issues and therefore some of them use the Windows on screen keyboard. One bit of feedback we've had is that the software is awkward to use with the OSK as too many important bits of the UI get covered up. If we could detect the presence of the keyboard we could adapt the UI to some extent.
Therefore is it possible in code to detect that the Windows in-built OSK is open? And is it possible in code to detect the location of the keyboard?
The application is in WinForms and usually runs on full desktops/laptops - not smaller touchscreen machines.

Related

What is 'Desktop Presence'? (As used in the Windows UI style guidelines)

A lot of the Windows style guidelines refer to 'Desktop Presence' in various places, e.g. http://msdn.microsoft.com/en-us/library/windows/desktop/dn742496(v=vs.85).aspx', but it's never defined anywhere that I can see.
Is there a definition for what exactly they mean by this?
Is it the presence of a normal window on the screen throughout the execution of the application? Do apps that occasionally appear on screen (with dialogs or notifications), but are predominantly hidden count? What about applications you can interact with on the desktop but only on demand, e.g. the wireless network connection menu?
Found an ok answer in the article I initially linked to, in the end (http://msdn.microsoft.com/en-us/library/windows/desktop/dn742496(v=vs.85).aspx):
"The taskbar is the access point for programs displayed on the desktop, even if the program is minimized. Such programs are said to have desktop presence."

How to replace Windows 8 volume indicator overlay?

New to Windows 8 and 8.1 is a volume overlay that sits above all other windows, and displays for 3-5 seconds every time you press one of the special volume buttons present on many keyboards.
Please note that I am not talking about this:
But rather this:
Which appears in the top left corner of the monitor.
I would like an API or something that will disable the display of this indicator when volume buttons are pressed on the keyboard.
Does something like this exist? Programming language doesn't matter, as I can convert from whatever to whatever, but for reference I will be implementing this in C++
There is not a documented method for disabling the UI, and I'd expect that any technique for doing so would rely on potentially risky/unsupported APIs/techniques.
The UI is now provided by Microsoft to enable a standardized experience for volume control across all devices. Some applications like the Microsoft Music application expect the volume control to be present so that they appear together.
In Win 8.1, all Media handling support was moved to the SystemMediaTransportControls. An app has only a tiny bit of control over display: IsEnabled.
If possible, you might consider relying on the built in support -- as they're not likely to go away, and it's unlikely that you'll be able to control them in the manner you want.

How to reliably give a window focus?

I need to give a Chrome window focus over all other running applications. Javascript's window.focus() only gives focus over other windows of the same browser.
When my Chrome extension executes:
chrome.windows.update(theWindowId, {focused: true});
I experience different behaviors on Mac versus Windows 7:
On a Mac, the intended window gains focus over all other running applications.
In Windows 7, the intended window gains focus only over other Chrome windows, but not over other running applications.
Does anyone know a way to reliably give the intended window focus over all applications on Windows?
Unfortunately, the chrome.windows.update() API is still very unreliable in how it handles window focus cross-platform. I've even noticed inconsistencies at various times in the same platform. A lot of this has to do with the varying security policies that different OSes use for window management, so there really isn't much that you can do about it in terms of how it functions for the end user who may or may not have applied the appropriate registry hack.

Does Windows 7 treat full-screen applications differently?

I have a hidden process that waits for non-standard hardware button messages and runs an application (with CreateProcess). No problem with the user disturbing, it's an action that the user approved himself. Everything is fine when it's usual layout with taskbar shown and multiply captioned and non captioned- windows. But the situation is different in XP and 7, when the current application is full-screen. Full-screen application in this case is window without borders having exactly the same dimension as the screen. Windows hides taskbar for such application even if it's always on.
In Xp, it's ok, the taskbar is being shown in this case and appication (for example calculator) also, the full-screen app is still visible in areas other than the launched app's and taskbar'. But in Windows 7 nothing visual happens, the full-screen app is still on and if I switch to taskbar, the executed application is there. I tried to solve it with SetForegroundWindow, BringWindowToTop, even AllowSetForegroundWindow(GetCurrentProcessId()) call for a window handle found with CreateProcess-WaitForIntputIdle-EnumThreadWindows, no change. So did something change since XP related to full-screen windows that officially documented?
Thanks,
Max
I would imagine that, if you have your own hardware device, that there is some API for generating "real" user input. Clearly the legacy keyboard and mouse, and now USB HID drivers (many of which are usermode I think?) have access to an API to do so.
Synergy+ for example can generate fake keyboard and mouse events on connected PCs, and the consequence of the faked input is windows switching activation normally.
So, my initial idea is for your usermode "Device" application to synthesize actual keyboard messages - SendInput seems a likely candidate for "the API that can "fake" real user input events.
Then, use an API like RegisterHotKey in your "UI" app to respond to the hotkey combination your device app generates.
Now, (assuming that SendInput IS generating user input events at the correct level), you should (from within the WM_HOTKEY handler in your UI app) have permission (because everything was "user initiated") to change the foreground window (to yourself).
Vista introduced the desktop composition feature. In short, all windows are drawing to a memory bitmaps and the Desktop Window Manager is then composing these bitmaps and drawing on a full-screen Direct3D surface. Full-screen windows do not participate in the desktop composition and get to draw directly on the screen (mostly because the majority of full-screen apps are games that need real-time screen updates).
In particular, this means that when a full screen app is up and running, it is covering the DWM composed image and the user needs to switch to a DWM-managed window for the DWM to start drawing on top of the full-screen app.
I don't have a good solution for your problem, unfortunately. One way to solve it would be to add the WS_CAPTION style to your app and then handle WM_NCPAINT/WM_NCCALCSIZE/WM_NCHITTEST yourself. This would allow you to lie to the DWM that you are a regular windowed application, but change visually your NC area to look like you have no title. However, this does require certain amount of additional code and might be a bit more effort you want to invest.
Another way you can try to solve your problem is to explicitly minimize your full-screen application window when launching the new process. However, you will then have to solve the problem of when to maximize it back again.
Btw, you might find the comments on this post from Raymond Chen interesting.
Windows supports multiple desktops and my guess would be that the full screen up is using a different desktop than the default one (where your application will be shown). A desktop object in Windows is "a logical display surface and contains user interface objects such as windows, menus, and hooks". For example, screen savers normally are started on a separate desktop.
You can find out which desktop an application is running on using Process Explorer:
Set Process Explorer to replace Task Manager and to run always on top.
When your full screen up is shown, launch Process Explorer by pressing Ctrl + Shift + Esc
Within Process Explorer, select the full screen process and press Ctrl + H to display the handles of this process
See the value of the Desktop item in the list. Usually this would be set to Default
If you know what desktop this app is running on you can start your process on the same desktop by first calling OpenDesktop to get a handle to this desktop and then pass it into the STARTUPINFO of your CreateProcess call.

Desktop app noob question: best cross-platform library that can listen for window-change events (focus, lose focus, etc)?

I've only ever done server, web, and database programming, never any desktop programming. I now want to learn and have a small project I want to attempt, but am not sure which library/framework to use.
I'd like to create a small cross-platform app that runs in the system tray (and whatever the OSX equivalent is), and listens for changes to windows on the Desktop. Specifically:
Windows XP, Vista, 7, Gnome, KDE, OSX. BSD, Android, and/or iOS would be nice too but not required.
Listens for when any window gains focus, loses focus, is opened or closed, or if the window title changes (for example when switching tabs in a tabbed browser). Any other information it can scrape from the window would be useful as well.
Can store these events, preferably in an embedded database like SQLLite.
The lighter-weight the better.
Includes an options GUI accessible via a right-click menu from the system-tray icon.
Preferably FOSS, but if you know any non-FOSS please list too.
Is there a single library or framework that can do all that across multiple platforms? QT? Python? Java? Something else? TIA.
Almost any GUI framework can easily let you know when your own application gains or loses focus (or the other operations you mention). However, listening for these events for other arbitrary applications is definitely platform-specific and may or may not even be possible.
One framework for doing this on Windows is the CBT callback hook. See the question CBT Hook not working in Windows Vista for information about possible limitations on using this technique.

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