can anyone tell me how screensaver works while windows is locked. what are the win32 api methods that are used.
The only knobs you have are LockWorkStation() to lock the workstation and SystemParametersInfo(), SPI_SETSCREENSAVEACTIVE to activate the screen saver. Everything else, switching the desktop, looking up the selected screen saver, loading and starting it is buried inside Windows. I'd guess at crss.exe. Your question is too vague to offer help beyond this.
Do you want to implement a screen saver or do you know how the screen saver can run while the machine is locked? On XP there is a separate desktop for this, which gets activated by the GINA (a DLL running in the winlogon process) when the machine is locked.
To implement a screen saver, implement ScreenSaverConfigureDialog and ScreenSaverProc according to the specifications over at MSDN, export those functions under these names (i.e. use a .def file to have the names without decoration) and name the created DLL .scr afterwards.
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I have a small warp server project on Windows that listen to a particular port and do something whenever I send a command to it by REST (for example: POST http://10.10.10.1:5000/print). It's a small client for printing PDF / receipt directly from another computer.
It works. But my problem is when I had to package the whole project, the Rust compiler give me an executable file (.exe). The application displays a terminal window when I run it. I want this terminal to be hidden somehow.
I try to run the program as a windows service (by using NSSM). It doesn't work for me since I had to access the printer. Windows doesn't allow my app to access any devices or any other executable as a windows service. (The reasons are explained here: How can I run an EXE program from a Windows Service using C#?)
So I plan to run my app as a tray-icon application so user can control or close the app. (https://github.com/olback/tray-item-rs)
Unfortunately, I still cannot hide the app's terminal window.
Another solution that I found is hstart (https://www.ntwind.com/software/hstart.html). But I would like to use this as "the last resort" solution since many antivirus/windows defender mark it as a malware.
Do anyone know how to hide or get rid of it ?
After lot of searching, It turns out to be easier than I thought. Just add
#![windows_subsystem = "windows"]
on top of your main.rs file. (for rust > 1.18) and the terminal is gone.
These control the /SUBSYSTEM flag in the linker. For now, only
"console" and "windows" are supported.
When is this useful? In the simplest terms, if you're developing a
graphical application, and do not specify "windows", a console window
would flash up upon your application's start. With this flag, it
won't.
https://doc.rust-lang.org/reference/runtime.html#the-windows_subsystem-attribute
https://blog.rust-lang.org/2017/06/08/Rust-1.18.html
https://learn.microsoft.com/en-us/cpp/build/reference/subsystem-specify-subsystem?view=msvc-170
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!
I've hit a bit of a stump on the road to my goal of creating a screen saver. Before I began this project I did research and everyone urged me to create the screen saver using flash.. in which I did. Now I face the issue of converting it to an SCR (screen saver format for windows) . Now I've done my research and downloaded Instantstorm only to be disappointed by it's lack of 64-bit support and/or Multi-monitor support (Scaled mirroring across screens if resolution of main screen is different from other screens).
Can anyone tell me what is the proper way of creating an animated screen saver from scratch (or from the flash file I created preferably) which is fully compatible with 64-bit and has the ability to display the screen saver on multiple monitors.
Since it's a flash app you may be able to run it through a browser/as a web page. See this post for additional info:
webpage as a screensaver windows 7 and XP?
When I create screensavers, I do it through java, and then use launch4j to convert it to a .exe file. I then rename that .exe file .scr.
If you have issues renaming the file, go to control panel>folder options and uncheck "hide extensions for known file types". You can then rename the file.
P.S. If you are able to create a .exe file with flash, then you can just rename it from .exe to .scr as the extenstion.
I need to starting my app when our USB device connected.
My first attempt at this is a background application that pays attention to when USB devices are plugged in. When it notices our device connected, it calls ShellExecute( ) and starts our application.
This works nicely except in Windows 8. Supposing we're on the "Start" screen in Windows 8. In that situation, the application starts in the background and the start screen remains in front.
I think this is a "focus" problem since what I'm actually hoping to do is "steal focus" from the Start screen.
http://blogs.msdn.com/b/oldnewthing/archive/2009/02/20/9435239.aspx
Since my background application doesn't have focus (the Start screen has focus; besides, my application doesn't have a UI), it can't give focus away to my foreground application.
Let me say that in general, I hate focus stealing. Starting the app the user wants to use is a great help to our users.
How can I fix this problem? Maybe the answer is to programmatically ask the start screen to start my app but I don't see a way to do that:
http://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/9ed23f32-0708-48a8-9ff7-5fce6dbe123f/windows-8-start-screen-api
Maybe I'm approaching this in the wrong way. Suggestions?
You're going about this the wrong way. Although you can write a program to constantly monitor the USB ports to detect when something is connected, there's no need. The OS is already doing that anyway.
Register an Autoplay handler for your device type and class. This is distinct from the old AutoRun feature, which would automatically execute programs found on an inserted file system.
You can begin with an overview of the feature from the November 2001 issue of MSDN Magazine.
Your handler will be a COM DLL. You can register the DLL as a handler, and register the handler with events you want to handle. You can either perform everything in the DLL, or you can put the bulk of the functionality in your application and just use the DLL as a proxy between the OS and your program.
I have a user that is currently running my Winforms app on Win7. My app allows users to select rows from an open Excel spreadsheet and drag-n-drop them onto the app. However, this user cannot do the drag-n-drop. The cursor changes to the "no" cursor (little circle with line through it) and the operation won't complete.
I was researching drag-n-drop and Win7 and everything I found points to UAC and/or UIPI. I was looking for some solutions and am not sure if any of the below would work:
If the user logs in as admin (and as a result runs my app as admin) would that allow drag-n-drop to work?
Does the user need to turn off or change the settings of UAC/UIPI in order to be able to drag-n-drop?
I am not sure what the issue is. My app usually runs from C:/Documents and Settings/... (C:/Users/... on Win7). Does where it is running from matter? Does drag-n-drop not work because the user is not running my app with enough permissions? Are his Excel and my app on different permission levels? If so, what can be done about that? Note that even though my app allows users to just drag the file directly, that doesn't work either.
Also, is there any way I can have the user reproduce this issue with other apps? Are there apps that come with Win7 that he can see the same problem with. For example, can this be reproduced using Notepad?
Thanks.
Explaining this problem away by UIPI is a very long stretch. It doesn't have anything to do with whether or not the user is logged-in as an admin, that doesn't affect UAC and your program will be running with that same account anyway. The only way UIPI could kick in to stop a D+D is when your program is elevated and Excel is not.
To get yourself elevated requires work and doesn't happen by accident. You'd have to include a manifest so that the user gets the UAC prompt, you'd know about that. Or the user would have to change the desktop shortcut and tick the "Run this program as an administrator" option, she's know about that. While UIPI can be bypassed for Windows messages (ChangeWindowMessageFilter), it cannot for Drag and Drop so if any elevation is going on then your stuck. The ultimate test is to simply ask the user to put the UAC slider all the way down.
The much more likely scenario is that your DragEnter event handler simply isn't happy with the data it sees and therefore doesn't assign the e.Effect property. If you can't get a debugger on-site then write a little test program that logs the values of e.Data.GetFormats() plus whatever else you use to check if the drop is acceptable. And don't forget the obvious: the user simply fumbling the drag somehow.