So I'm making an MFC application that handles a couple of different messages and will display different output based on which message was handled. So right now I have one that handles the WM_KEYDOWN message and displays that message's output. Now I also have one that handles WM_RBUTTONDOWN and what I want it to do is to start up the game of Brick Breaker that I am making. The issue that I'm having is that once I enter the WM_RBUTTONDOWN I want to disable certain keys so that I can control the paddle without calling the WM_KEYDOWN.
TL:DR How do you disable certain keys from the WM_KEYDOWNin MFC.
You can override PreTranslateMessage to see and bypass a message before MFC does its message map translation.
You shouldn't have to disable keys in your application. When another program has the focus, all input should go to that program.
You will want to forward the keys you are interested in to the code that drives your object.
You don't need to disable keys. It is simply up to your code to decide to process or not a key according to the state of the application.
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I am currently developing a user interface DLL that uses the WIN32 API. The DLL must work for numerous platforms, XP, WIN CE, etc. I have managed to incorporate docking, anchoring and so on but appear to have a problem regarding owner-drawn buttons. I can draw the button's correct state, focus, clicked, default. However, I cannot receive key notifications. I specifically want to perform a click operation on a button that currently has focus, should the user press enter.
Note that I am using a windows message loop rather than a dialog message loop. I use windows hooks to hook into the window creation and set the user data to 'point' to my control instance. If I test for WM_KEYDOWN in the main message loop I can get a handle to my button control instance and could forward the message to the relevant control. Unfortunately, I am dealing with a lot of legacy code and this may not be an ideal solution.
So, my question is what is the best way forward. Is subclassing the button control's window procedure a viable option or is there an easier way?
Many thanks in advance.
The comments above are correct. The button with focus should be getting the key messages. But buttons don't (by themselves) respond to Enter--they respond to Space. It sounds like what you're missing is the typical dialog keyboard navigation, like Tab key moving the focus and Enter activating the "default" button.
If you've got a typical Windows message pump, and you want the keyboard behavior normally associated with dialogs, then you need to use the IsDialogMessage API in your message loop. This means your window is essentially a "modeless dialog".
Looks like standard window proc subclassing should do the trick. See http://msdn.microsoft.com/en-us/library/windows/desktop/ms633591(v=vs.85).aspx for details.
Alright, I want to write a program that intercepts mouse and keyboard events before they are reported to the active window/application, whatever that may be. Based on my program logic I want to be able to send custom key events.
For example: When the mouse button is held down, for any key press, send the next alphabetical letter. So if I hold down the right mouse button and hit 'a', the application sees it as a 'b' keypress.
I have briefly researched hooks and methods of intercepting WinAPI messages, and I'm unclear as to whether this is the solution I am looking for or not. According to what I've read, some of these solutions require you to inject a DLL into the desired application; my program needs to work for any running application.
Also, I have noticed that most of these solutions are in C#. As a matter of personal preference I would like to use C++ to write this program. Is there any reason why I would need to use C#?
Any pointers or advice is appreciated.
I try to send a mouse click event to a game application. First, i use Spy++ to find what message the application receive. I see something like : WM_MOUSEACTIVATE, WM_WINDOWPOSCHANGING, WM_ACTIVATEAPP, WM_ACTIVATE, WM_SETFOCUS, ...
i try to send the same as i see on Spy++ but it doesn't work. How to send mouse click to a game application without give it focus? . it's run in window mode. Thanks in advance.
You want WM_LMOUSEDOWN. You can always check MSDN for the documentation on which messages mean what.
The best way to automate applications and games is via SendInput. While in theory it should be possible to drive an application via WM_LUBTTONDOWN etc, many applications read the key state directly via lower level APIs (such as GetAsyncKeyState) which don't change their state to reflect the messages processed from the message queue.
Using SendInput requires actually setting the game to the foreground as the input events are synthesized at a low level and are thus delivered to the active/focused window.
I have a third party encryption library, which may create a MessageBox if key creation fails. The failure can be caused by bad random number generation or other rarities, and in most cases, trying again will result in success. My code will attempt key creation up to three times before deciding it failed.
Now, the issue is that the program may be used with automation. If a MessageBox is created during automation, it will block the process forever, because there's nobody to click the 'OK' button.
Does anyone know of a way to catch when this message box is created and automatically close it?
Anything is fair game, as long as it's not something that will make security suites angry. This means no hooking or code tunneling.
In summary, I need to catch when a MessageBox is created and close it. The MessageBox's creation is outside of my control. Modifying the code at runtime is not acceptable.
Also, I've noticed there are some other similar questions, but they don't have the same requirements.
EDIT: Additional note, I can find the message box via searching through all windows until I find one with a matching title and then send it a WM_CLOSE message, but I don't think this is a great solution. I also have no guarantee that the message box has been/will be displayed, or how long after my call it will be displayed. It could display instantly, it could display 1200 ms later, or it could not display at all.
Just before you begin the encryption process, install a WH_CBT hook, and in its callback watch for an nCode of HCBT_CREATEWND. If you get a matching class name ('#32770 (Dialog)' ?) and a matching title either return a nonzero value from the callback, or if that doesn't work post a WM_CLOSE (or a BM_CLICK to a relevant button if selecting an option is necessary). Uninstall the hook after the process for not messing with every possible dialog your application pops up.
That sounds like bad design on the part of that library. Generally any sort of utility library (like encryption) has no business invoking any kind of GUI (unless you explicitly ask it to).
Is there possibly some configuration or setting in this library that could disable its use of message boxes?
If not, I'd suggest that you might want to investigate using a different library. After all, if the designers of this library have already made this kind of poor design decision once, then there may be other unfortunate surprises lurking in there.
You can hope that it will be found by GetForegroundWindow, but this may catch other applications. The more brute force way is to iterate over all windows with EnumWindows looking for something that has a caption or text equal to this shown by the library.
I have once "remote controlled" an application by sending mouse click events to some controls. I guess you would have to do this in a separate thread that is watching for Events if a window is opened. Pretty ugly but working...
Create a new thread. If your function fails and a Message Box is opened, obtain a handle to the message box by looping through the windows (GetTopWindow, GetNextWindow) and comparing the window's process id to the one returned from GetCurrentProcessId().
Or, you can avoid all the hard work and just hook the MessageBox API with detours. It's not very hard, and if you don't want to pay for detours, you can do it manually.
Call VirtualProtect and set the memory protection at MessageBox at PAGE_EXECUTE_READWRITE
Create a naked function, and use it as a trampoline.
Create a function identical in parameters to MessageBox (this will be your hook)
Create a jump from MessageBox to your hook function.
i am using an mfc ListCtrl, is there anyway to know if a selection change was caused by mouse/keyboard input rather than a programatic change? i am after the same behaviour as ON_LBN_SELCHANGE for a listbox. thanks
You can use GetKeyState() to find out whether a key or mouse button was pressed. Do not use GetAsyncKeyState() because that API will tell you the current state of the keyboard/mouse buttons, which may have changed when you handle the LBN_SELCHANGE message. GetKeyState() however will tell you the state as it was when LBN_SELCHANGE was generated.
AFAIK there is no way to find out this information. You know if you are sending the message to the CListCtrl so you should set a flag if you do. If the LBN_SELCHANGE message is received and the flag has NOT been set then it must have come from a keyboard/mouse.