Hey everyone, I'm making a program that will be able to watch and record some mouse pixel coordinates when I click the left mouse button anywhere on the screen. However I haven't been able to retrieve the mouse pixel coordinates out of the DLL that contains the function. I'm using windows WH_MOUSE_LL hook for reading the data. Basically I need to figure out how to get the mouseX and mouseY from the DLL into my separate program. Here's my code:
main.cpp
The DLL's main.h fileCode:#include <windows.h> #include <iostream> #include "C:\Users\JohnJr\Desktop\My Programs\Hooks\MouseHook.h" #include "C:\Users\JohnJr\Desktop\My Programs\Hooks\HookProcs\main.h" /* Declare Windows procedure */ LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM); /* Make the class name into a global variable */ char szClassName[ ] = "CodeBlocksWindowsApp"; MouseHook* h = 0; int WINAPI WinMain (HINSTANCE hThisInstance, HINSTANCE hPrevInstance, LPSTR lpszArgument, int nCmdShow) { HWND hwnd; /* This is the handle for our window */ MSG messages; /* Here messages to the application are saved */ WNDCLASSEX wincl; /* Data structure for the windowclass */ /* The Window structure */ wincl.hInstance = hThisInstance; wincl.lpszClassName = szClassName; wincl.lpfnWndProc = WindowProcedure; /* This function is called by windows */ wincl.style = CS_DBLCLKS; /* Catch double-clicks */ wincl.cbSize = sizeof (WNDCLASSEX); /* Use default icon and mouse-pointer */ wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION); wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION); wincl.hCursor = LoadCursor (NULL, IDC_ARROW); wincl.lpszMenuName = NULL; /* No menu */ wincl.cbClsExtra = 0; /* No extra bytes after the window class */ wincl.cbWndExtra = 0; /* structure or the window instance */ /* Use Windows's default colour as the background of the window */ wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND; /* Register the window class, and if it fails quit the program */ if (!RegisterClassEx (&wincl)) return 0; /* The class is registered, let's create the program*/ hwnd = CreateWindowEx ( 0, /* Extended possibilites for variation */ szClassName, /* Classname */ "Code::Blocks Template Windows App", /* Title Text */ WS_OVERLAPPEDWINDOW, /* default window */ CW_USEDEFAULT, /* Windows decides the position */ CW_USEDEFAULT, /* where the window ends up on the screen */ 544, /* The programs width */ 375, /* and height in pixels */ HWND_DESKTOP, /* The window is a child-window to desktop */ NULL, /* No menu */ hThisInstance, /* Program Instance handler */ NULL /* No Window Creation data */ ); /* Make the window visible on the screen */ ShowWindow (hwnd, nCmdShow); h = new MouseHook(); bool exiting = false; if(!h->SetFunction("C:/Users/JohnJr/Desktop/My Programs/Hooks/HookProcs/bin/Debug/HookProcs.dll")) MessageBoxA(hwnd, "Error setting function", "Error", MB_ICONEXCLAMATION); while(!exiting) // Loop That Runs Until Ending Program { if (PeekMessage(&messages,NULL,0,0,PM_REMOVE)) // Is There A Message Waiting? { if (messages.message==WM_QUIT) // Have We Received A Quit Message? { exiting=TRUE; // If So done=TRUE } else // If Not, Deal With Window Messages { TranslateMessage(&messages); // Translate The Message DispatchMessage(&messages); // Dispatch The Message } } else // If There Are No Messages { // Execute main program if(h->isSet()) std::cout << mouseX; } } /* The program return-value is 0 - The value that PostQuitMessage() gave */ return messages.wParam; } /* This function is called by the Windows function DispatchMessage() */ LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) { switch (message) /* handle the messages */ { case WM_DESTROY: PostQuitMessage (0); /* send a WM_QUIT to the message queue */ break; case WM_KEYUP: if(wParam == VK_SPACE) h->Set(); else if(wParam == VK_ESCAPE) h->UnSet(); break; default: /* for messages that we don't deal with */ return DefWindowProc (hwnd, message, wParam, lParam); } return 0; }
the main.cpp of DLLCode:#ifndef __MAIN_H__ #define __MAIN_H__ #include <windows.h> #include <iostream> /* To use this exported function of dll, include this header * in your project. */ #ifdef BUILD_DLL #define DLL_EXPORT __declspec(dllexport) #else #define DLL_EXPORT __declspec(dllimport) #endif #ifdef __cplusplus extern "C" { #endif int mouseX = 0; int mouseY = 0; DLL_EXPORT LRESULT CALLBACK MProc(int nCode, WPARAM wParam, LPARAM lParam); #ifdef __cplusplus } #endif #endif // __MAIN_H__
In the programs main, I try to access the mouseX from the DLL, however it always displays 0, even though there is no longer a linker error. Can anyone explain why it remains 0? Thanks in advance!Code:#include "main.h" // a sample exported function DLL_EXPORT LRESULT CALLBACK MProc(int nCode, WPARAM wParam, LPARAM lParam) { if(nCode < 0) return CallNextHookEx(NULL, nCode, wParam, lParam); //Check wParam here if (wParam == WM_LBUTTONUP) { MOUSEHOOKSTRUCT * hHook = (MOUSEHOOKSTRUCT*)lParam; mouseX = hHook->pt.x; mouseY = hHook->pt.y; } return CallNextHookEx(NULL, nCode, wParam, lParam); } BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) { switch (fdwReason) { case DLL_PROCESS_ATTACH: // attach to process // return FALSE to fail DLL load break; case DLL_PROCESS_DETACH: // detach from process break; case DLL_THREAD_ATTACH: // attach to thread break; case DLL_THREAD_DETACH: // detach from thread break; } return TRUE; // succesful }
