This is related to my other question.
I used the OnStructureChanged event to detect that the 'Help' window popped up in the 3rd party application that my application is writing data to. I need my application to pause while the end user resolves the data issue in the 3rd party application, then I need my application to resume once the end user closes the 'Help' window. (Either I need to detect that the 'Help' window was closed or I need to display a message box and use the DialogResult to trigger my application to resume).
I've never encountered something like this before. I don't know if it's possible to do what I want to do. If it is possible, I don't know where to start.
Advice?
UPDATES:
I have only used Threading once before and I think it was a fairly "easy peasy" usage, I pulled it off without much effort, considering I'd never used Threading before. I'm playing around with Threading for this issue right now. There's a good chance I've implemented it incorrectly, but my app isn't functioning correctly anymore...I don't know if I'm even playing with the correct tool.
I had to just keep moving with the project - deadlines, you know...
I ended up using UI Automation to detect the "Help" window, then I showed a message box giving instructions to the end user. I check the MessageBox's DialogResult and continue processing based on that. It might not be the "best" way to skin the cat, but I'm a noob and I have a deadline, so I did what I needed to do to keep moving.
Related
I am writing an application in c# to lock or freeze all programs untill user enters a value in the app's textbox and clicks ok.
The purpose of the app would be to get people to enter their time.
As far as I know you can set it to top most but they can end the app with task manager so am stuck here..
formName.TopMost = true;
Any help would be appreciated
Yes, that's correct. The Windows operating system allows multiple programs to run at one time. What you're experiencing is entirely by design.
If I remember correctly, the TopMost property applies only to windows in your process, and as you mention, it's all quite irrelevant: the user can still kill your application using the Task Manager.
There's no legitimate way of getting around that. It's not a "limitation", it's a feature. Any app that prevents itself from being closed by the Task Manager is treading dangerously closely on the category of software that we call malware. Nothing good can come out of pursuits like this.
Relevant reading: The arms race between programs and users
Perhaps a good compromise solution is to make your window/form actually top-most and disable the Close button so that the user knows they shouldn't try and close it. This is almost always enough to stop a user that is not determined to end your application by any means necessary, and that's about all you should ever be concerned with.
See the sample code here for how to make your window/form always appear on top of other running applications by setting the WS_EX_TOPMOST flag or toggling HWND_TOPMOST.
I've also already written a detailed answer here about disabling the Close button the correct way by setting the CS_NOCLOSE class style.
I am currently a developer working on a very task specific application; the user(s) are often multitasking so they can often make errors inputting data. The nature of the task makes notifying them of those imputation mistakes important. We currently use a combination of panels and labels and/or a small label at the bottom of the application in order to notify them of something happening. In the near future we will be tasked to update interface for the application.
Recently while looking up an unrelated question I came across the following question:
click here for link the answer caught my eye and setting the owner’s handle to zero (null) did indeed do what the author asked.
Since I have only recently started working with importing and working with unmanaged code in C# I was wondering if there were any “side effects” of using this method. I of course realize that the user could cause the application to open a ton of message box(s). I have in the past attempted to use a thread-safe message box and found the requirement of our application always being on top was an issue (the location of the message box was hidden by the application).
I was able to take to test the code against the requirement, and it appears to have similar issues as the method I found but appears we could work around those issues. I did think of something that could be done, I realy need to figure out how to determine where on the screen the message box will be displayed.
In order to address Jim's concerns one has to understand that the application that is running is processing data continously. So currently anything that locks the main thread, can cause problems processing this data, which is task critical. We get around this problem using labels, but with our future task I am looking for a more streamline approach to present these error messages. The main problem is the solution also must not additional overhead to the application. Some additional tid-bits of information is that the system is used on a closed network.
I suppose the short question would have to be, are there any negatives of using this particular method, to show a non-blocking messagebox in C#?
There's no particular technical problem with displaying modal message boxes by setting the window handle to null. I question its use as a UI error message indication, because it doesn't prevent the user from continuing in the face of error.
Modal message boxes that make the user hit OK and then correct the error make for a terribly clunky user interface. But a popup that might be hidden and lets the user keep going is just as bad. There are much better solutions, some of which are shown in the validation examples for Windows Forms (and, presumably WPF).
Boring background:
I have been working with UltraVNC to control some PC's at work and it does the job great but in order to simplify things I created a program that interfaces with it in C#. Basically I take advantage of the commands the viewer offers to connect, control, watch or transmit to each PC.
Problem is anyone can access the PC's since it has one main account (no domain controller). I need everyone to sign for the PC before they can use it, so to make my job easier I open each PC and block the inputs + blank the screen that way there obligated to sign before use.
Opening each pc and press the block button can be hassle especial when you’re helping someone and a user leaves, others come (btw I work at an electronic library). UltraVNC doesn’t have a command for this; it’s been requested but I don’t think it’s much of a priority for them and the code seems very intimidating for a novice like me so I thought I could try a hack to get what I want.
Problem: I want to “click” a button in a program I use, from an application that I am building in c#. I can currently use the process class to get the handle and identify the specific window I want to use but I have no way to find the button handle which I read is what I need. I found stuff about using findwindow and sendkeys for this but I don’t see how that’ll work unless the button had a keystroke assigned to it which it doesn’t.
So can anyone point me in the right direction?
Why not use something like Eficium Cybercafe SurfShop to achieve what you want? After teh user finished you log the session out, and before someone can log in, they have to sign in.
I want to create an alarm app for myself. On certain conditions (i need to poll websites) i want my app to inform me and make it HARD TO MISS. So i can take appropriate action or ignore it if i need to do something else.
I wrote a test app and using a BalloonTip (ShowBalloonTip with notifyIcon) isnt great. One of my previous apps brings the window in front of you and does a MessageBox however that doesnt always work or work well (if i somehow miss it or accidentally forget to click ok no futher messages will occur).
What are your suggestions?
You could also make it a system tray application and change the icon out if there is something which requires attention, a la a messenger application. That may not be "hard to miss" but I am trained (for better or worse) to look down at the icon tray when I see something blinking.
Where I work, we have a TimeTracker application (built in house) with which developers are supposed to log what we worked on and when. I am notorious for not using it. So, I wrote my own (Windows Forms) version for my own use which, every hour opens up and takes over my screen:
It is a frameless dialog which consumes the entire screen.
TopMost = True.
On resize, it sets WindowsState = Normal and resizes to fill the screen.
While it is open, it polls for taskmgr.exe and procexp.exe and kills them if found.
It disables the start menu to prevent cmd.exe commands from the menu in Windows 7.
The only way to close it is to enter a log, only then is the OK button shown!
So far, it's working out well - no one has been able to break it!
My less drastic suggestion would be to have a notification which pops up momentarily above the system tray. After a second or two, fade it out. Keep showing the notification every 30 seconds or so until it is dismissed.
Always-on-top window in the corner of the screen?
You could always set your window to be a top most window, make it full screen, and activate it. It would be very, very hard to miss...
Granted, it would also be very annoying, and not something I'd do to other users...
My "real" suggestion would be to use sound along with standard notification methods if this is going to be used by other people, as that's an easy way to grab attention without necessarily killing their workflow. A modeless window that appears in a corner of the screen, especially if combined with sound and color, can be very effective to grab attention.
The industry has been adopting these ambient orb devices and variations of it when such a hard-to-miss notification is required. It is used for tracking the stock-market and for broken-daily-builds.
http://www.ambientdevices.com/cat/orb/MAN_Ambient%20Orb_3-23-03.pdf
Regards
I've been teaching myself how to use messages with Window's APIs, and have actually been doing very well learning them. Problem is, I can't figure out how to receive a message from another application to start code within mine.
Essentially, what I want to do is allow others using a commercial application to click the save button (on the commercial application), and have my application stop the save message, prompt the user, and from that either cancel the save to allow them to continue, or allow the save (which I know how to do now through messages).
I just need to know how to catch a message, and stop it. If anyone can point me to an API call, or function, or just documentation that may help, please do.
Check out Detours by Microsoft Research. It's possible, but not simple. Also, look into how client-side game cheats are performed. I will not link any of them here, but they are out there. That's essentially what you want to do.
I think you'll need to attach your own application to the running process the same way a debugger would... Unless the commercial application has a custom method of plugging into their architecture to do this.
The next question is... do you want to proceed down this path.