I am trying to determine if User Account Control is currently blacking out the screen/asking for permission.
I have an application which uses SlimDX and when UAC takes over the screen it causes the DirectX device to be lost, I can recreate the device once the UAC window has been closed, if I try this before(even in a try{}catch{} and loop the application crashes)
I have looked over at pinvoke and msdn and I can't seem to find anything about this. Does anyone have an ideas?
As a note: I do not want to interact with these prompts in any way, I only want to check if they are open so I can delay the creation of my DirectX device.
Sorry for making a late answer. But I think it may help.
As far as I see, you are not looking for a way to see if UAC is running, but a way to check whether UAC is blocking the screen.
I've confirmed that UAC is using SwitchDesktop to change to another desktop, so you can just use GetInputDesktop to get the 'active' desktop. Then use GetUserObjectInformation to check its name. The 'normal' desktop should be default, while UAC will be running on the WinLogon desktop.
Wish it will help.
If a UAC prompt is currently on screen then C:\Windows\System32\consent.exe will be running. There are ways to be notified with a event when a program starts or stops, you can use them and have your program perform the action to recreate the DirectX device after the consent.exe program terminates.
Related
I've written a WPF/C#-based "shell" which launches WPF apps or other apps.
What would be the best method for checking if the process is finally fully launched or no longer "busy"? I've noticed that the mouse cursor for the launched process stays at the busy cursor from initial launch until I can finally see the UI for the process. Could I use User32.SetCapture API to set the mouse capture to the external process, then somehow check if the mouse cursor is the busy cursor? Or perhaps there's a mechanism in the System.Diagnostics.Process class that I'm unaware of?
As some of the launched apps are pre-compiled third-party apps, I absolutely cannot implement a mechanism in the external processes to message if it is finally ready, such as: Microsoft PowerPoint 2010 Viewer, Adobe Acrobat, or Adobe Flash Player Standalone.
I can't just check if the process has been created, because then I have a blank, unresponding window and a busy cursor. I hope to hide my WPF app the moment the external process is done launching.
The WaitForInputIdle Win32 APi function will wait until given process enters the message loop (with no input pending).
Quote: "Before trying to communicate with the child process, the parent process can use the WaitForInputIdle function to determine when the child's initialization has been completed."
You can call it via P/Invoke.
Not very cear what do you mean saying "beasy", but hear are several considerations:
There is no known (clear) way, at least that I'm aware of, that can let you do something like that. The thing is that process is perfectly isolated OS kernel citizen. So you can not write something that works for all type processes, especially if they are 3rd part binaries.
What you can try to do, is get the MainWindow of the process (if there is any), get its handle, and filter OS messages untill you get for example WM_ACTIVATED.
But even if this could work in certain situations, in others can measurably fail. For example, process loaded but the program is not active, cause for some reason License window of the application appeared.
Let's see what others suggest, in my opinion, there is no generic and no single solution to cover minority of possible cases.
Good luck
I'm interested in launching a window in a temporary session, like how UAC prompts appear. There's been some interest in this concept from a few people, so I figured I'd ask here. Essentially what we're going for is an elevated window like the UAC "are you sure you want to <...>" prompts, but with an arbitrary window. The end goal is to prevent window event hooks and all sorts of other issues that might occur during password entry.
I've had a quick look at the UAC APIs and a few other places, but there's nothing particularly useful out there. Obviously the UAC prompts get elevated to their own desktop session somehow, so there must be a way to create windows in such a way.
You can create a desktop using CreateDesktop. You can use SwitchDesktop to switch to the new desktop. Then you can call SetThreadDesktop on your main thread and draw your window. To get back get the handle of the default desktop by calling OpenDesktop with "Default" as lpszDesktop and use SwitchDesktop with this handle. You can also run Processes on a certain desktop. In order to do this you have to set lpDesktop member of the STARTUPINFO structure to the name of the desktop the process should be run on. Close the handles to the desktops after using them (CloseDesktop).
You can show your own window on an own desktop in this way.
The secure desktop used by UAC and by the Logon UI is called "Winlogon". In order to access it you need system rights. Luke provided an example in one of his answers.
Brian R. Bondy wrote a blog entry on desktops and window stations which is worth reading.
I'm creating a WP7 app that needs to continue running when the user is not using the phone - ideally the user sets it going, locks the phone and carries on with their life.
Is this possible?
I know it is possible to disable the lock screen, so if the user were to just leave the phone on a table it would be fine and carry on running. The problem is when they put it in their pocket - buttons will get pressed such at the windows/home button, and if this happens then the app is tombstoned straight away.
Any ideas if this is possible? Either somehow locking the phone without tombstoning the app, or implementing a sort of custom lock screen and handling the events for all the hardware buttons including the windows/home button?
Any suggestions will be appreciated.
Just as you figured out:
PhoneApplicationService.Current.ApplicationIdleMode = IdleDetectionMode.Disabled
No need to ask user for permission anymore (since the original 6.3.1 "Configurable Functionality" was dropped). However, there are other Marketplace certification requirements to consider, see section 6.3: http://go.microsoft.com/fwlink/?LinkID=183220
I think I've done it again - asking questions too soon.
I believe the following setting:
PhoneApplicationService.Current.ApplicationIdleMode = IdleDetectionMode.Disabled
will enable the application to run under a lock screen.
I'm writing a software for a call-center. It's somewhat like a ATM program: user can only interactive with it, not with underlying Windows. It takes controls when user logs in to Windows, and when user exits, it logs off Windows.
How can I do that in .NET? A demo will be much appreciated.
Thank you.
Replace the Windows Shell.
By that I mean Explorer.exe, by means of editing the Windows Registry. What this does for you is instead of logging on and the system running Explorer.exe which consists of the Start Menu, Taskbar and other similar features you are familiar with, it only runs your program. There is no desktop, no context menu, no taskbar, or start menu. Thus, making your application "The Shell" or the new "Explorer.exe".
However, by doing this the user still has access to Control+Alt+Delete, so they would still be able to access the Windows Task Manager, which mind you can also be disabled via a simple Registry Key Entry.
This is the most pain free, easiest solution because you don't even have to worry about things such as disabling the WindowsKey or other annoyances.
The registry key to this is as follows:
SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
The name of the value to modify is:
Shell
And you can simply enter the value to be the fully qualified path to your program's executable file. You will only want to do this under HKEY_CURRENT_USER and only for the account that is to run your shell program. So you will need two separate accounts.
Administrator account
This account will just be a normal password protected account that will be used to manage the system
Kiosk account
This account will be the account that is logged on at all times, which runs your custom shell (your application)
Additional Notes
To disable the Task Manager the registry path is as follows:
Software\Microsoft\Windows\CurrentVersion\Policies\System
The name of the value is:
DisableTaskMgr
This is a DWORD value which to enforce the policy must be set to '1'.
What I did was to use DirectX and just use full-screen and exclusive modes, which you can see a small example of here: http://www.directxtutorial.com/tutorial9/b-direct3dbasics/dx9B2.aspx.
This is more work, but it will allow you to do what you want.
Depending on what control you have, there are steps you can do with group policy to limit what people can do on the computer. You can look at how people set up a kiosk application on Windows for some ideas.
What you want to do is run the OS in "kiosk mode".
This entails using the Group Policy Management Console to apply the kiosk mode template - as part of this you register your application as the shell.
As such there is no taskbar, or explorer view to fall back on to. The only way to run the usual shell would be to connect a keyboard to the system - press ctl-alt-delete and run explorer from the taskmanager that pops up.
And you can disable even the standard task manager if users are going to have keyboard access to the console. You will want to implement some kind of launch explorer.exe interface otherwise the system might become a bit difficult to manage :P
You can set your applications window to be always on top and to cover the entire screen. If you exclude buttons that close the window the user must know that ALT+F4 closes the window in order to exit. This has been good enough for me those times I've needed it.
we would like to build a screensaver that shows the desktop and the running applications but prevents user input by showing the login screen. The idea was to build a windows app with no window or a transparent window. However, as soon as the screensaver gets activated the desktop and all applications are hidden from the screen.
Is it possible to start the screensaver without hiding the desktop?
Thx,
bja
Is it possible for you to implement this as something other than a screensaver? I'm assuming that the Windows API does have a method that allows you to tell how long the computer has been idle (otherwise, how does the stuff that manages screensavers do it?), so if you use that you could just set up your application such that it's continuously running as a background process, and will pop up a modal dialog box (or your idea of a transparent window) or something that prompts for the user's login info when the computer has been idle for a certain amount of time.
Why can't you just grab an image of the screen when the SS kicks off. Then use that as the backdrop of your SS.
Vista has a bubbles screen saver that just starts putting bubbles on the screen. Not sure how they do it.
You are better off just creating a full-screen application with a transparent window that starts up on a timer like a screensaver. The screensaver functionality while similar to what you are doing, functions much differently.
As an alternative suggestion, you could always use a service (or background app) to gather the information you want these monitoring tools to display, or even just to grab periodic screenshots of the (hidden) desktop, and then have your screensaver query that app to get the data it needs to display.
That way, you get the benefit (the secure desktop, the usual Windows login sequence, etc.) of a screensaver, but still get to display what you need to.