Not receiving pointer after calling GetWindowLongPtr with GWLP_USERDATA - c++

I have a Window procedure which I have defined in a class and I need to be able to access the class' members using the this pointer.
The Window procedure:
static LRESULT CALLBACK TextWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
MyCustomClass* self =
reinterpret_cast<MyCustomClass*>(
GetWindowLongPtr(hWnd, GWLP_USERDATA) // Not recieving the pointer!
);
switch(message) {
case WM_DESTROY: {
SetWindowLongPtr(hWnd, GWLP_WNDPROC, (LONG_PTR)self->origWndProc); // I am subclassing btw.
break;
}
case WM_PAINT: {
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hWnd, &ps);
HBRUSH hBrush = (HBRUSH)GetStockObject(NULL_BRUSH);
FillRect(hdc, &ps.rcPaint, hBrush);
SetBkMode(hdc, TRANSPARENT);
DrawText(hdc, L"OK", -1, &ps.rcPaint, DT_CENTER | DT_VCENTER | DT_SINGLELINE);
SetBkMode(hdc, OPAQUE);
EndPaint(hWnd, &ps);
DeleteObject(hBrush);
break;
}
case WM_LBUTTONDOWN: {
printf("%d", self->x); // Crashes the program
break;
}
}
return CallWindowProc(self->origWndProc, hWnd, message, wParam, lParam); // Subclassing!
}
Now after creating the window (a text control in my case) I am immediately setting the pointer to the class using SetWindowLongPtr, like this:
// Variable in the class that holds the `HWND` data to the text control.
this->textControl = CreateWindow(
L"STATIC",
L"Hello World!",
WS_CHILD | WS_VISIBLE | SS_NOTIFY,
this->x, this->y, this->width, this->height, // Position and size, members defined in the class
this->parentWindow, // Parent window.
0,
NULL,
NULL
);
SetWindowLongPtr(this->textControl, GWLP_USERDATA, (LONG_PTR)this); // Setting the pointer
this->origWndProc = (WNDPROC)SetWindowLongPtr(this->textControl, GWLP_WNDPROC, (LONG_PTR)this->TextWndProc); // Setting the window procedure for "Subclassing"!
But the problem is I am not receiving the this pointer when I am calling GetWindowLongPtr as seen in the Window procedure.
Am I calling it wrong? I don't know what is wrong.
Any help would be greatly appreciated! Thank you in advance!

Related

Painting colored text to c++ win32

Is it possible to paint colored text to what I've already done?
I've tried WM_CTLCOLORSTATIC, CreateSolidBrush(), and several other functions.
//-----------------------------------
// Learning the win32 API for C++
//
// Created by: Cosmic Cruizer
//-----------------------------------
#include <windows.h>
#include <tchar.h>
// Function declarations
bool SetUpWindowClass (char*, int, int, int); // Remove window structure from WinMain and put into function
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM) // Pre-declare Windows procedure/function
// Global variables
const char CLASS_NAME[] = "My Window Class Array"; // declared for window class; Can be static or const
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,LPSTR lpCmdLine, int nCmdShow){
//Step 1: Registering the Window Class
HWND hwnd{}; // This is the handle for our window
MSG msg{}; // Handle for messages to the application
SetUpWindowClass (NULL, NULL, NULL, NULL); // The Window structure - removed from main and made into a function
// Step 2: Creating the Window
hwnd = CreateWindowEx( // returns a handle to the new window, or zero if the function fails
WS_EX_CLIENTEDGE, // Optional window styles. Can be set to 0
CLASS_NAME, // Name of window class, see set 1b. Also set as the constant
"My First C++ Windows App", // Window title text
WS_OVERLAPPEDWINDOW, // Window style, title bar, a border, a system menu, and Minimize and Maximize buttons.
200, 200, 500, 400, // Size and position
NULL, NULL, hInstance, NULL); // Parent window, Menu, Instance handle, Additional app data
// Add an exit button
CreateWindow(
"BUTTON", // Predefined class; Unicode assumed
"EXIT", // Button text
WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON, // Styles
200, 200, 60, 25, // x position, y position, Button width, Button height
hwnd, // Parent window
NULL, // No menu.
(HINSTANCE)GetWindowLongPtr(hwnd, GWLP_HINSTANCE), NULL); // Pointer not needed.
ShowWindow(hwnd, nCmdShow); // Make the window visible on the screen
// Step 3: The Message Loop
while(GetMessage(&msg, NULL, 0, 0) != 0) { // Run the message loop. It will run until GetMessage() returns 0
TranslateMessage(&msg); // Translate virtual-key messages into character messages
DispatchMessage(&msg); // Send message to WindowProcedure
}
return msg.wParam;
}
//---------- Functions ----------//
// Setup the window structure
bool SetUpWindowClass (char *cpTitle, int iR, int iG, int iB) {
//Step 1a: The Window structure
WNDCLASSEX wc{}; // Data structure for the windowclass
wc.cbSize = sizeof(WNDCLASSEX); // Sets the size of the Windows API
wc.style = 0; // define additional elements of the window class
wc.lpfnWndProc = WndProc; // defines most of the behavior of the window. See setp 4 "LRESULT CALLBACK WndProc" function
wc.cbClsExtra = 0; // No extra bytes after the window class
wc.cbWndExtra = 0; // structure for the window instance
wc.hInstance = GetModuleHandle (NULL); // handle to the application instance.
wc.hIcon = LoadIcon(NULL, IDI_APPLICATION); // handle to icon class, if NULL, system provides a default icon.
wc.hCursor = LoadCursor(NULL, IDC_ARROW); // handle to cursor class
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+18); // Add color as the background of the window
wc.lpszMenuName = NULL; // No menu
wc.lpszClassName = CLASS_NAME; // string that identifies the window class
wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
//Step 1b: Register the window class, and if it fails quit the program
if (RegisterClassEx (&wc)) return true;
else return false;
}
// Step 4: the Window Procedure in this function
LRESULT CALLBACK WndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam){
switch(uMsg){
case WM_CLOSE:{
DestroyWindow(hwnd);
break;
}
case WM_COMMAND:{ // Close the window when exit is pressed
if (MessageBox(hwnd, "Really quit?", "Exit Warning", MB_OKCANCEL) == IDOK){ // what the hell, just wanted this.
PostQuitMessage(0);
}
break;
}
case WM_DESTROY:{
PostQuitMessage(0);
break;
}
//--- trying to create colored text ---//
case WM_CTLCOLORSTATIC:{
HDC hdcStatic = (HDC) wParam; // handle to display context
hwnd = (HWND) lParam; // handle to control window
SetTextColor(hdcStatic, RGB(100,255,255));
SetBkColor(hdcStatic, RGB(250,250,6));
return (INT_PTR)CreateSolidBrush(RGB(250,250,100));
}
case WM_CTLCOLOREDIT:{
HDC hdcStatic = (HDC) wParam;
SetTextColor(hdcStatic, RGB(0,0,255));
SetBkColor(hdcStatic, RGB(0,230,0));
return (INT_PTR)CreateSolidBrush(RGB(0,230,0));
}
case WM_PAINT:{ // All painting (text) occurs here, between BeginPaint and EndPaint.
PAINTSTRUCT ps; // Holds info about current painting session.
HDC hdc = BeginPaint(hwnd, &ps); // Create the device context (DC)
// Each character is added to the cpaText array. Then the for loop goes through and paints each character
int iY = 7; // Vertical spaces and number of lines for the array
const char *cpaText [iY] = { // changed from char to const char to get rid of warning. and added 1 for each line and a return
"Hello Peoples",
"",
"This is my first attempt to program using the Win32 API.",
"I can only hope it gets better with time.",
"",
"Created by \"The\" Cosmic Cruizer"
};
for (int iLoopCounter = 0; cpaText [iLoopCounter] != 0; iLoopCounter++, iY += 20) {
TextOut (hdc, 5, iY, cpaText [iLoopCounter], strlen (cpaText [iLoopCounter]));
}
EndPaint(hwnd, &ps); // Free up HDC created with BeginPaint
break;
}
default:{
return DefWindowProc(hwnd, uMsg, wParam, lParam); // Return is needed either here or at the end
break;
}
}
return DefWindowProc(hwnd, uMsg, wParam, lParam); // Return is needed either here or in the default case
}
WM_CTLCOLORSTATIC and WM_CTLCOLOREDIT are notification messages used by STATIC/EDIT controls, neither of which you have on your window, so you will never receive those messages and should remove those handlers from your code.
You are trying to draw colored text directly onto your window using TextOutA() in a WM_PAINT handler, which is fine. But per the TextOutA() documentation:
The TextOut function writes a character string at the specified location, using the currently selected font, background color, and text color.
Your WM_PAINT handler is not selecting anything into the HDC that BeginPaint() returns, before trying to draw on it. It simply needs to configure the desired font/color values as desired, eg:
HFONT hFont;
LRESULT CALLBACK WndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam){
switch(uMsg){
...
case WM_CREATE:{
hFont = CreateFont(...); // or CreateFontIndirect()
break;
}
case WM_DESTROY:{
DeleteObject(hFont);
PostQuitMessage(0);
break;
}
case WM_SETTINGCHANGE:
case WM_FONTCHANGE:{
DeleteObject(hFont);
hFont = CreateFont(...); // or CreateFontIndirect()
InvalidateRect(hwnd, NULL, TRUE);
break;
}
case WM_PAINT:{
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hwnd, &ps);
HFONT hOldFont = (HFONT) SelectObject(hdc, hFont);
SetTextColor(hdc, ...);
SetBkColor(hdc, ...);
int iY = 7;
const char *cpaText [iY] = {
"Hello Peoples",
"",
"This is my first attempt to program using the Win32 API.",
"I can only hope it gets better with time.",
"",
"Created by \"The\" Cosmic Cruizer"
};
for (int iLoopCounter = 0; cpaText [iLoopCounter] != 0; iLoopCounter++, iY += 20) {
TextOutA (hdc, 5, iY, cpaText [iLoopCounter], strlen (cpaText [iLoopCounter]));
}
SelectObject(hdc, hOldFont);
EndPaint(hwnd, &ps);
return 0;
}
...
}
return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

Change window's background color with button using winapi

I'm trying to make button change background color of window when clicked. I know that I need to handle this event in WM_COMMAND, where I also check ID of this button, but nothing happens. I tried to debug and my program recognizes ID correctly. The piece of code used for changing color works well when in main loop but it doesn't do anything when in WM_COMMAND. How do I solve this problem? Whole code:
#include <Windows.h>
#define BUTTON_ID 100
struct status_info {
const char* waiting = "Waiting for connection...";
const char* connected = "Connected.\nWaiting for frajer to copy number.";
const char* changed = "Number changed.";
}status_info;
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);
int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE, PWSTR pCmdLine, int nCmdShow) {
const wchar_t CLASS_NAME[] = L"Name";
WNDCLASS wc = {};
wc.lpfnWndProc = WindowProc;
wc.hInstance = hInstance;
wc.lpszClassName = (LPCSTR)CLASS_NAME;
wc.hbrBackground = (HBRUSH)GetStockObject(GRAY_BRUSH);
RegisterClass(&wc);
//main window
HWND hwnd = CreateWindowEx(0, (LPCSTR)CLASS_NAME, (LPCSTR)"Hacker", WS_OVERLAPPEDWINDOW | WS_VISIBLE, CW_USEDEFAULT, CW_USEDEFAULT, 500, 300, NULL, NULL, hInstance, NULL);
//number window
HWND number = CreateWindowEx(WS_EX_WINDOWEDGE, TEXT("Static"), TEXT("Account number:\n00 1234 1234 1234 1234 1234 1234"), WS_CHILD | WS_VISIBLE, 5, 5, 240, 40, hwnd, NULL, NULL, NULL);
//status window
const char* status_message = status_info.waiting;
HWND status = CreateWindowEx(WS_EX_WINDOWEDGE, TEXT("Static"), TEXT(status_message), WS_CHILD | WS_VISIBLE, 5, 55, 240, 40, hwnd, NULL, NULL, NULL);
//button
HWND button = CreateWindowEx(0, "BUTTON", "Nightmode", WS_CHILD | WS_VISIBLE, 100, 100, 150, 30, hwnd, (HMENU)BUTTON_ID, hInstance, NULL);
MSG msg;
WNDCLASS okno;
while (GetMessage(&msg, (HWND)NULL, 0, 0)) {
TranslateMessage(&msg);
DispatchMessage(&msg);
SetWindowText(status, status_message);
}
return msg.wParam;
return 0;
}
LRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_CREATE:
//MessageBox(hwnd, L"1", L"1", 0);
return (0);
case WM_DESTROY:
//MessageBox(hwnd, L"2", L"2", 0);
PostQuitMessage(0);
return (0);
case WM_COMMAND: {
if (LOWORD(wParam) == BUTTON_ID) {
PAINTSTRUCT ps;
RECT rc;
HDC hdc = BeginPaint(hwnd, &ps);
GetClientRect(hwnd, &rc);
SetBkColor(hdc, BLACK_BRUSH);
ExtTextOut(hdc, 0, 0, ETO_OPAQUE, &rc, 0, 0, 0);
EndPaint(hwnd, &ps);
}
break;
}
default:
return DefWindowProc(hwnd, message, wParam, lParam);
}
}
BeginPaint/EndPaint should be used in response to WM_PAINT only.
You can use GetDC(hwnd)/ReleaseDC(hwnd, hdc) to obtain hdc for painting on device context outside of WM_PAINT, but this will be temporary. The next refresh message causes the window to be erased and repainted according to what's in WM_PAINT
SetDCBrushColor can be used if the goal is to avoid creating brush handle.
static COLORREF bkcolor = RGB(255,255,255);
switch(message)
{
case WM_COMMAND:
if(LOWORD(wparam) == BUTTON_ID)
{
bkcolor = RGB(255, 0, 0);
InvalidateRect(hwnd, NULL, TRUE);
}
break;
case WM_PAINT:
{
PAINTSTRUCT ps;
RECT rc;
HDC hdc = BeginPaint(hwnd, &ps);
GetClientRect(hwnd, &rc);
SetDCBrushColor(hdc, bkcolor);
FillRect(hdc, &rc, (HBRUSH)GetStockObject(DC_BRUSH));
//or use ps.rcPaint to repaint only the section which requires update
//FillRect(hdc, &ps.rcPaint, (HBRUSH)GetStockObject(DC_BRUSH));
EndPaint(hwnd, &ps);
return 0;
}
case WM_ERASEBKGND:
//return 0 means WM_PAINT handles the background
return 0;
Alternatively, use SetClassLongPtr to replace the background brush:
static HBRUSH bkbrush = NULL;
switch(message)
{
case WM_COMMAND:
if(LOWORD(wparam) == BUTTON_ID)
{
COLORREF bkcolor = RGB(rand() % 256, rand() % 256, rand() % 256);
if(bkbrush)
DeleteObject(bkbrush);
bkbrush = CreateSolidBrush(bkcolor);
SetClassLongPtr(hwnd, GCL_HBRBACKGROUND, (LONG)bkbrush);
InvalidateRect(hwnd, NULL, TRUE);
}
break;

WINapi. Can't erase background of window with ellipse

I'm just trying to draw an ellipse:
case WM_PAINT:
hdc = BeginPaint(parentWindow, &ps);
Ellipse(hdc, x, y, width, height);
EndPaint(parentWindow, &ps);
, and then erase it with drawing a new ellipse with some new parameters every second using timer:
case WM_CREATE:
SetTimer(hWnd, 1, 1000, NULL);
break;
case WM_TIMER:
x += 5;
InvalidateRect(hWnd, NULL, TRUE);
break;
But ellipses are not erased and layered:
However, i tried to trace WM_ERASEBKGND and it really is sent every InvalidateRect.
Full code:
#include <Windows.h>
#include <windowsx.h>
#include <tchar.h>
#include <iostream>
TCHAR szWindowClass[] = TEXT("CreateThreadWindow");
TCHAR szAppName[] = TEXT("CreateThreadExample");
BOOL InitWindow(HINSTANCE, int);
ATOM MyRegisterClass(HINSTANCE);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
HWND parentWindow;
MSG msg;
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
MyRegisterClass(hInstance);
if (!InitWindow(hInstance, nCmdShow))
return FALSE;
BOOL bRet;
while ((bRet = GetMessage(&msg, (HWND)NULL, 0, 0)) != 0)
{
if (bRet == -1)
return FALSE;
else
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
}
return (int)msg.wParam;
}
ATOM MyRegisterClass(HINSTANCE hInstance)
{
WNDCLASS wndClass;
memset(&wndClass, 0, sizeof(wndClass));
wndClass.lpfnWndProc = WndProc;
wndClass.hInstance = hInstance;
wndClass.lpszMenuName = NULL;
wndClass.lpszClassName = szWindowClass;
return RegisterClass(&wndClass);
}
BOOL InitWindow(HINSTANCE hInstance, int nCmdShow)
{
parentWindow = CreateWindow(szWindowClass, szAppName, WS_OVERLAPPEDWINDOW,
300, 0, 600, 600, NULL, NULL, hInstance, NULL);
ShowWindow(parentWindow, nCmdShow);
return TRUE;
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wparam, LPARAM lparam)
{
PAINTSTRUCT ps;
HDC hdc;
static int x = 0, y = 0, width = 200, height = 100;
switch (message) {
case WM_ERASEBKGND:
_RPT1(0, "%s\n", "erase");
break;
case WM_PAINT:
hdc = BeginPaint(hWnd, &ps);
Ellipse(hdc, x, y, width, height);
EndPaint(hWnd, &ps);
break;
case WM_CREATE:
SetTimer(hWnd, 1, 1000, NULL);
break;
case WM_TIMER:
x += 5;
InvalidateRect(hWnd, NULL, TRUE);
break;
case WM_DESTROY:
PostQuitMessage(0);
return 0;
default:
return DefWindowProc(hWnd, message, wparam, lparam);
}
}
Your code isn't erasing anything. It's just drawing an ellipse at the specified coordinates. The previously-drawn ellipse is still there.
You mention the WM_ERASEBKGND message, but there are two reasons why that isn't working for you:
In your window procedure (WndProc), you handle the WM_ERASEBKGND message explicitly, which means that it doesn't get passed to the default window procedure (DefWindowProc). A better way to write your window procedure would be the following:
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wparam, LPARAM lparam)
{
static int x = 0, y = 0, width = 200, height = 100;
switch (message) {
case WM_ERASEBKGND:
{
_RPT1(0, "%s\n", "erase");
break;
}
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hWnd, &ps);
Ellipse(hdc, x, y, width, height);
EndPaint(hWnd, &ps);
return 0;
}
case WM_CREATE:
{
SetTimer(hWnd, 1, 1000, NULL);
break;
}
case WM_TIMER:
{
x += 5;
InvalidateRect(hWnd, NULL, TRUE);
return 0;
}
case WM_DESTROY:
{
PostQuitMessage(0);
return 0;
}
default:
break;
}
return DefWindowProc(hWnd, message, wparam, lparam);
}
Now, the default window procedure gets called every time, unless you explicitly return from inside of a case label.
When you register your window class (inside of MyRegisterClass), you zero all fields of the WNDCLASS structure and then explicitly initialize a couple of them. You don't explicitly initialize the hbrBackground field, so it is being set to 0. And when hbrBackground is 0,
When this member is NULL, an application must paint its own background whenever it is requested to paint in its client area. To determine whether the background must be painted, an application can either process the WM_ERASEBKGND message or test the fErase member of the PAINTSTRUCT structure filled by the BeginPaint function.
This means that the default window procedure isn't doing anything in response to the WM_ERASEBKGND message because you didn't give your window a background brush.
You will either need to set hbrBackground to something like COLOR_WINDOW + 1, or you will need to add code to your WM_ERASEBKGND message handler to erase the window's background yourself.
Or, perhaps an even better option would be to forget about the WM_ERASEBKGND message altogether, as many Windows programmers do, because this two-step erase-and-paint approach tends to cause flicker. Leave the hbrBackground field set to NULL, don't do anything in response to the WM_ERASEBKGND message, and do your erasing at the top of the WM_PAINT handler:
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hWnd, &ps);
// Erase background of entire client area.
RECT rcClient;
GetClientRect(hWnd, &rcClient);
FillRect(hdc, &rcClient, reinterpret_cast<HBRUSH>(COLOR_WINDOW+1));
// Do normal drawing.
Ellipse(hdc, x, y, width, height);
EndPaint(hWnd, &ps);
return 0;
}

Uninitialized Local Variable in Switch Statement - Win32 API

Alright here is my code I will just provide one function sense the rest of it would not be any helpful. I have been searching for the problem and can not seem to figure it out.
Error: uninitialized local variable 'hTextBox' used Win32Project2
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)
{
HDC hdc;
RECT rect;
PAINTSTRUCT ps;
HWND hTextBox;
switch (message)
{
case WM_CREATE:
hTextBox = CreateWindow(L"edit", L"", WS_CHILD|WS_VISIBLE|WS_BORDER, 5, 5, 200, 25, hwnd, NULL, NULL, NULL);
CreateWindow(L"button", L"Click me!", WS_CHILD | WS_VISIBLE, 20, 40, 75, 25, hwnd, (HMENU)1, NULL, NULL);
break;
case WM_COMMAND:
switch (LOWORD(wparam))
{
case 1:
int returnedCharacters = 0;
returnedCharacters = GetWindowText(hTextBox, &szTextSaved[0], 20);
break;
}
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
GetClientRect(hwnd, &rect);
DrawText(hdc, L"This is a text message!", -1, &rect, DT_CENTER | DT_VCENTER);
EndPaint(hwnd, &ps);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
}
return DefWindowProc(hwnd, message, wparam, lparam);
}
It is not static, so it won't remember what happened in WM_CREATE

Importing a BitMap makes my Window Lagg

I need some help here.
Im importing an bitmap onto my Win32 Window. I am building it and after some seconds it's starting to lag a lot. I am not sure why, but I suppose I am not correctly deleting it from memory after using it.
Thank you for Help in advance.
I saw a behavior while I was testing it. If Im not moving the window than it is okey, but after moving it it start to lag and block my IDE. Maybe something with WM_PAINT?
Here is my code.
#include <windows.h>
//For more makros
#include <windowsx.h>
#include "Simulatron.h"
HINSTANCE hProgramInstance;
Simulatron Exo;
char Simulatron::m_szClassName[] = "Simulatron";
Simulatron::Simulatron(HINSTANCE hInstance)
{
m_hInstance = hInstance; // Save Instance handle
m_wndClass.cbSize = sizeof(WNDCLASSEX); // Must always be sizeof(WNDCLASSEX)
m_wndClass.style = CS_DBLCLKS; // Class styles
m_wndClass.lpfnWndProc = MainWndProc; // Pointer to callback procedure
m_wndClass.cbClsExtra = 0; // Extra bytes to allocate following the wndclassex structure
m_wndClass.cbWndExtra = 0; // Extra bytes to allocate following an instance of the structure
m_wndClass.hInstance = hInstance; // Instance of the application
m_wndClass.hIcon = NULL;//LoadIcon(hInstance, MAKEINTRESOURCE(IDC_MAINCURSOR)); // Class Icon
m_wndClass.hCursor = LoadCursor(NULL, IDC_ARROW); // Class cursor
m_wndClass.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); // Background brush
m_wndClass.lpszMenuName = NULL; // Menu Resource
m_wndClass.lpszClassName = (LPCWSTR)m_szClassName; // Name of this class
m_wndClass.hIconSm = NULL;//LoadIcon(hInstance, MAKEINTRESOURCE(IDI_APP_ICON)); // Small icon for this class
}
Simulatron::~Simulatron()
{
}
Simulatron::Simulatron()
{
// If we declare a window class with a default constructor,
// we need to reset the window to a nothing
}
LRESULT CALLBACK Simulatron::MainWndProc (HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
static HDC hdc;
static PAINTSTRUCT ps;
static HDC hdc_mem;
static HBRUSH newbrush;
//Child Window Handles
Simulatron create;
RECT rect;
hProgramInstance = (HINSTANCE)GetWindowLong(hwnd, GWL_HINSTANCE);
static HBITMAP logo = NULL;
static BITMAP bitmap;
logo = (HBITMAP)LoadImage(hProgramInstance, L"Space.bmp", IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
GetObject(logo, sizeof(bitmap), &bitmap);
switch (msg)
{
case WM_CREATE:
{
create.Create(hProgramInstance,hwnd,lParam,logo);
}
break;
case WM_GETMINMAXINFO:
{
LPMINMAXINFO pInfo = (LPMINMAXINFO) lParam;
//pInfo -> ptMaxTrackSize.x = 450;
//pInfo -> ptMaxTrackSize.y = 650;
}
break;
case WM_SIZE:
break;
case WM_CTLCOLORSTATIC:
SetTextColor((HDC)wParam, RGB(150, 100, 255));
SetBkMode((HDC)wParam, TRANSPARENT);
newbrush = (HBRUSH)GetStockObject(NULL_BRUSH);
DeleteObject(newbrush);
return (LRESULT)newbrush;
break;
case WM_COMMAND:
break;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
GetClientRect(hwnd , &rect);
hdc_mem = CreateCompatibleDC(hdc);
SelectObject(hdc_mem, logo);
BitBlt(hdc, 0, 0, bitmap.bmWidth, bitmap.bmHeight, hdc_mem, 0, 0, SRCCOPY);
DeleteObject(hdc_mem);
EndPaint(hwnd, &ps);
break;
//Handle the combinations from the keyboard input
case WM_DESTROY:
PostQuitMessage (0);
DeleteObject(logo);
DeleteBitmap(logo);
break;
default:
return DefWindowProc (hwnd, msg, wParam, lParam);
}
return 0;
}
//Create function of all Childs
void Simulatron::Create(HINSTANCE Hinst, HWND hWindow, LPARAM lParam, HBITMAP logo)
{
Hinst = ((LPCREATESTRUCT) lParam) -> hInstance; // handle to instance for custom cursor
logo = (HBITMAP)LoadImage(Hinst, L"Space.bmp", IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
}
bool Simulatron::Run(int nCmdShow)
{
if(!RegisterClassEx(&m_wndClass))
return false;
m_hwnd = CreateWindowEx(0,(LPCWSTR)m_szClassName,
L"Simulatron",
//WS_OVERLAPPEDWINDOW,
WS_OVERLAPPED | WS_CAPTION | WS_SYSMENU | WS_THICKFRAME | WS_MINIMIZEBOX | WS_MAXIMIZEBOX, // Dissable Resizing and Maximizing
0, 0, 1280, 1000,
NULL, NULL,
m_hInstance,
NULL);
if(!m_hwnd)
return false;
ShowWindow(m_hwnd, nCmdShow);
return true;
}
Simulatron::operator HWND()
{
// This overloaded operator allows us to use HWND anyway we want
return m_hwnd;
}
You load the BMP File over and over again in your MainWndProc. You should load it once at Init and use it from there! Have a look at a win32 API tutorial and you will see that MainWndProc is getting called throughout the whole program lifetime. You could load that image in your WM_CREATE state for example.