RichEdit's text not visible when window first pops up.

Question

#include <Windows.h>
#include <Richedit.h>
HWND hwnd;
HWND hwnd_richedit_panel;
HWND richEdit;
WNDPROC oldStaticProc;
HWND hwnd_green_panel;
WNDPROC oldGreenProc;
int WINAPI WinMain(HINSTANCE, HINSTANCE, PSTR, int);
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK StaticProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK GreenPanelProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
#define RICHEDIT_CLASS L"RICHEDIT50W"
#if _DEBUG
#pragma comment( linker, "/subsystem:console" )
int main(int argc, const char** argv) {
	return WinMain(GetModuleHandle(NULL), NULL, GetCommandLineA(), SW_SHOWDEFAULT);
}
#else
#pragma comment( linker, "/subsystem:windows" )
#endif
#pragma comment(lib, "opengl32.lib")
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {
    HMODULE hMod = LoadLibrary(TEXT("Msftedit.dll"));
    if (!hMod)
    {
        // Handle the error
        MessageBox(NULL, L"Failed to load Msftedit.dll", L"Error", MB_OK | MB_ICONERROR);
        return 1; // Or some other error handling
    }
  
    int width = 800;
    int height = 600;
    WNDCLASS wc = { };
    const wchar_t* CLASS_NAME = L"OpenGL and RichEdit Message Processing";
    wc.lpfnWndProc = WindowProcedure;
    wc.hInstance = hInstance;
    wc.lpszClassName = CLASS_NAME;
    if (!RegisterClass(&wc))
    {
        MessageBox(NULL, L"Window Registration Failed!", L"Error!", MB_ICONEXCLAMATION | MB_OK);
    }
    hwnd = CreateWindowEx(
        0,
        CLASS_NAME,
        L"OpenGL RichEdit Control",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, width, height,
        NULL,
        NULL,
        hInstance,
        NULL
    );
    if (hwnd == NULL)
    {
        MessageBox(NULL, L"Window Creation Failed!", L"Error!", MB_ICONEXCLAMATION | MB_OK);
    }
    // Subclass the "STATIC" class
    WNDCLASS wcStatic = { };
    GetClassInfo(NULL, L"STATIC", &wcStatic);
    oldStaticProc = wcStatic.lpfnWndProc;
    wcStatic.lpfnWndProc = StaticProc;
    wcStatic.lpszClassName = L"STATIC_SUBCLASS";
    RegisterClass(&wcStatic);
    hwnd_richedit_panel = CreateWindowEx(
        0,
        L"STATIC_SUBCLASS",
        NULL,
        WS_CHILD | WS_VISIBLE,
        0, height - 150, width, 150,
        hwnd,
        NULL,
        hInstance,
        NULL
    );
    if (hwnd != NULL)
    {
        ShowWindow(hwnd, SW_SHOW);
        UpdateWindow(hwnd);
    }
    if (hwnd_richedit_panel != NULL)
    {
        InvalidateRect(hwnd_richedit_panel, NULL, TRUE);
        UpdateWindow(hwnd_richedit_panel);
    }
    // Move the creation of the richEdit control here
    richEdit = CreateWindowEx(
        WS_EX_CLIENTEDGE,
        RICHEDIT_CLASS,
        L"Type here...",
        WS_CHILD | WS_VISIBLE | WS_VSCROLL | ES_MULTILINE | ES_AUTOVSCROLL,
        0, 0, width, 150,
        hwnd_richedit_panel,
        NULL,
        hInstance,
        NULL
    );
    if (richEdit == NULL)
    {
        // Handle the error
        MessageBox(NULL, L"RichEdit Creation Failed...", L"Error!", MB_ICONEXCLAMATION | MB_OK);
        return 1; // Or some other error handling
    }
    // After creating the RichEdit control
    BOOL result = SendMessage(richEdit, WM_SETTEXT, 0, (LPARAM)L"Hello, World!");
    if (!result)
    {
        // Handle the error
        DWORD dwError = GetLastError();
        MessageBox(NULL, L"SendMessage Failed...", L"Error!", MB_ICONEXCLAMATION | MB_OK);
        return 1; // Or some other error handling
    }
    SetWindowPos(richEdit, HWND_TOP, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);
    SendMessage(richEdit, EM_SETSEL, 0, 0);
    SendMessage(richEdit, EM_SCROLLCARET, 0, 0);
    // Show the RichEdit control and force it to repaint
    ShowWindow(richEdit, SW_SHOW);
    UpdateWindow(richEdit);
    RedrawWindow(richEdit, NULL, NULL, RDW_INVALIDATE | RDW_UPDATENOW | RDW_ERASE);
    // In your WinMain function, after creating hwnd_richedit_panel:
    // Subclass the "STATIC" class for the green panel
    WNDCLASS wcGreen = { };
    GetClassInfo(NULL, L"STATIC", &wcGreen);
    oldGreenProc = wcGreen.lpfnWndProc;
    wcGreen.lpfnWndProc = GreenPanelProc;
    wcGreen.lpszClassName = L"GREEN_SUBCLASS";
    RegisterClass(&wcGreen);
    hwnd_green_panel = CreateWindowEx(
        0,
        L"GREEN_SUBCLASS",
        NULL,
        WS_CHILD | WS_VISIBLE,
        0, 0, width, height - 150,
        hwnd,
        NULL,
        hInstance,
        NULL
    );
    if (richEdit == NULL)
    {
        DWORD dwError = GetLastError();
        LPVOID lpMsgBuf;
        FormatMessage(
            FORMAT_MESSAGE_ALLOCATE_BUFFER |
            FORMAT_MESSAGE_FROM_SYSTEM |
            FORMAT_MESSAGE_IGNORE_INSERTS,
            NULL,
            dwError,
            MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
            (LPTSTR)&lpMsgBuf,
            0, NULL);
        MessageBox(NULL, (LPCTSTR)lpMsgBuf, L"Error", MB_OK | MB_ICONERROR);
        LocalFree(lpMsgBuf);
    }
    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
	return 0;
}
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    static HBRUSH hBrush = CreateSolidBrush(RGB(0, 255, 0));
    switch (msg)
    {
    case WM_ERASEBKGND:
        return TRUE;
    case WM_CTLCOLORSTATIC:
    {
        //HDC hdcStatic = (HDC)wParam;
        //SetBkColor(hdcStatic, RGB(0, 255, 0));
        //return (INT_PTR)hBrush;
    }
    case WM_SIZE:
    {
        int width = LOWORD(lParam);
        int height = HIWORD(lParam);
        SetWindowPos(hwnd_richedit_panel, NULL, 0, height - 150, width, 150, SWP_NOZORDER);
        SetWindowPos(hwnd_green_panel, NULL, 0, 0, width, height - 150, SWP_NOZORDER);
        // Adjust the size and position of richEdit to fill the entire client area of hwnd_richedit_panel
        SetWindowPos(richEdit, NULL, 0, 0, width, 150, SWP_NOZORDER);
        InvalidateRect(hwnd_richedit_panel, NULL, TRUE);
        InvalidateRect(hwnd_green_panel, NULL, TRUE);
        break;
    }
    case WM_CLOSE:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}
LRESULT CALLBACK StaticProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    HPEN hPen = {}; HPEN hOldPen = {}; HDC hdc = {};
    switch (msg)
    {
    case WM_ERASEBKGND:
    {
        HDC hdc = (HDC)wParam;
        RECT rect;
        GetClientRect(hwnd, &rect);
        FillRect(hdc, &rect, (HBRUSH)(COLOR_WINDOW + 1));
        return TRUE;
    }
    case WM_PAINT:
        PAINTSTRUCT ps;
        hdc = BeginPaint(hwnd, &ps);
        // Create a rectangle that is slightly smaller than the panel
        RECT rect;
        GetClientRect(hwnd, &rect);
        rect.left += 2;
        rect.top += 2;
        rect.right -= 2;
        rect.bottom -= 2;
        // Create a pen (for drawing lines) that is red and 2 pixels wide
        hPen = CreatePen(PS_SOLID, 2, RGB(255, 0, 0));
        // Select the pen into the device context
        hOldPen = (HPEN)SelectObject(hdc, hPen);
        // Draw a rectangle that is the same size as the panel
        Rectangle(hdc, rect.left, rect.top, rect.right, rect.bottom);
        // Clean up: deselect the pen, delete it, and end the paint operation
        SelectObject(hdc, hOldPen);
        DeleteObject(hPen);
        EndPaint(hwnd, &ps);
        break;
    default:
        return CallWindowProc(oldStaticProc, hwnd, msg, wParam, lParam);
    }
    return 0;
}
LRESULT CALLBACK GreenPanelProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    HPEN hPen = {}; HPEN hOldPen = {}; HDC hdc = {};
    switch (msg)
    {
    case WM_ERASEBKGND:
    {
        //HDC hdc = (HDC)wParam;
        //RECT rect;
        //GetClientRect(hwnd, &rect);
        //HBRUSH hbr = CreateSolidBrush(RGB(0, 255, 0)); // Change to the color you want
        //FillRect(hdc, &rect, hbr);
        //DeleteObject(hbr);
        return TRUE;
    }
    case WM_PAINT:
        PAINTSTRUCT ps;
        hdc = BeginPaint(hwnd, &ps);
        // Create a rectangle that is slightly smaller than the panel
        RECT rect;
        GetClientRect(hwnd, &rect);
        rect.left += 2;
        rect.top += 2;
        rect.right -= 2;
        rect.bottom -= 2;
        // Create a pen (for drawing lines) that is green and 2 pixels wide
        hPen = CreatePen(PS_SOLID, 2, RGB(0, 255, 0));
        // Select the pen into the device context
        hOldPen = (HPEN)SelectObject(hdc, hPen);
        // Draw a rectangle that is the same size as the panel
        Rectangle(hdc, rect.left, rect.top, rect.right, rect.bottom);
        // Clean up: deselect the pen, delete it, and end the paint operation
        SelectObject(hdc, hOldPen);
        DeleteObject(hPen);
        EndPaint(hwnd, &ps);
        break;
    default:
        return CallWindowProc(oldGreenProc, hwnd, msg, wParam, lParam);
    }
    return 0;
}

The "Hello World!" text is not visible when the window first pops up on the screen however it does display if the window is re-sized by dragging out or in the corner of the window with the mouse. How can I modify the code so that the "Hello World!" text is visible when the window first opens to the screen?

Answer 1

Hello,

Welcome to Microsoft Q&A!

As far as I'm concerned, you should creat hwnd_green_panel first and then create the hwnd_richedit_panel.

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {

	HMODULE hMod = LoadLibrary(TEXT("Msftedit.dll"));

	if (!hMod)

	{

		// Handle the error

		MessageBox(NULL, L"Failed to load Msftedit.dll", L"Error", MB_OK | MB_ICONERROR);

		return 1; // Or some other error handling

	}


	int width = 800;

	int height = 600;

	WNDCLASS wc = { };

	const wchar_t* CLASS_NAME = L"OpenGL and RichEdit Message Processing";

	wc.lpfnWndProc = WindowProcedure;

	wc.hInstance = hInstance;

	wc.lpszClassName = CLASS_NAME;

	if (!RegisterClass(&wc))

	{

		MessageBox(NULL, L"Window Registration Failed!", L"Error!", MB_ICONEXCLAMATION | MB_OK);

	}

	hwnd = CreateWindowEx(

		0,

		CLASS_NAME,

		L"OpenGL RichEdit Control",

		WS_OVERLAPPEDWINDOW,

		CW_USEDEFAULT, CW_USEDEFAULT, width, height,

		NULL,

		NULL,

		hInstance,

		NULL

	);

	if (hwnd == NULL)

	{

		MessageBox(NULL, L"Window Creation Failed!", L"Error!", MB_ICONEXCLAMATION | MB_OK);

	}



	// In your WinMain function, after creating hwnd_richedit_panel:

	// Subclass the "STATIC" class for the green panel

	WNDCLASS wcGreen = { };

	GetClassInfo(NULL, L"STATIC", &wcGreen);

	oldGreenProc = wcGreen.lpfnWndProc;

	wcGreen.lpfnWndProc = GreenPanelProc;

	wcGreen.lpszClassName = L"GREEN_SUBCLASS";

	RegisterClass(&wcGreen);

	hwnd_green_panel = CreateWindowEx(

		0,

		L"GREEN_SUBCLASS",

		NULL,

		WS_CHILD | WS_VISIBLE,

		0, 0, width, height - 150,

		hwnd,

		NULL,

		hInstance,

		NULL

	);





	// Subclass the "STATIC" class

	WNDCLASS wcStatic = { };

	GetClassInfo(NULL, L"STATIC", &wcStatic);

	oldStaticProc = wcStatic.lpfnWndProc;

	wcStatic.lpfnWndProc = StaticProc;

	wcStatic.lpszClassName = L"STATIC_SUBCLASS";

	RegisterClass(&wcStatic);

	hwnd_richedit_panel = CreateWindowEx(

		0,

		L"STATIC_SUBCLASS",

		NULL,

		WS_CHILD | WS_VISIBLE,

		0, height - 150, width, 150,

		hwnd,

		NULL,

		hInstance,

		NULL

	);

	if (hwnd != NULL)

	{

		ShowWindow(hwnd, SW_SHOW);

		UpdateWindow(hwnd);

	}

	if (hwnd_richedit_panel != NULL)

	{

		InvalidateRect(hwnd_richedit_panel, NULL, TRUE);

		UpdateWindow(hwnd_richedit_panel);

	}

	// Move the creation of the richEdit control here

	richEdit = CreateWindowEx(

		WS_EX_CLIENTEDGE,

		RICHEDIT_CLASS,

		L"Type here...",

		WS_CHILD | WS_VISIBLE | WS_VSCROLL | ES_MULTILINE | ES_AUTOVSCROLL,

		0, 0, width, 150,

		hwnd_richedit_panel,

		NULL,

		hInstance,

		NULL

	);

	if (richEdit == NULL)

	{

		// Handle the error

		MessageBox(NULL, L"RichEdit Creation Failed...", L"Error!", MB_ICONEXCLAMATION | MB_OK);

		return 1; // Or some other error handling

	}

	// After creating the RichEdit control

	BOOL result = SendMessage(richEdit, WM_SETTEXT, 0, (LPARAM)L"Hello, World!");

	if (!result)

	{

		// Handle the error

		DWORD dwError = GetLastError();

		MessageBox(NULL, L"SendMessage Failed...", L"Error!", MB_ICONEXCLAMATION | MB_OK);

		return 1; // Or some other error handling

	}

	SetWindowPos(richEdit, HWND_TOP, 0, 0, 0, 0, SWP_NOMOVE | SWP_NOSIZE);

	SendMessage(richEdit, EM_SETSEL, 0, 0);

	SendMessage(richEdit, EM_SCROLLCARET, 0, 0);

	// Show the RichEdit control and force it to repaint

	ShowWindow(richEdit, SW_SHOW);

	UpdateWindow(richEdit);

	RedrawWindow(richEdit, NULL, NULL, RDW_INVALIDATE | RDW_UPDATENOW | RDW_ERASE);


	if (richEdit == NULL)

	{

		DWORD dwError = GetLastError();

		LPVOID lpMsgBuf;

		FormatMessage(

			FORMAT_MESSAGE_ALLOCATE_BUFFER |

			FORMAT_MESSAGE_FROM_SYSTEM |

			FORMAT_MESSAGE_IGNORE_INSERTS,

			NULL,

			dwError,

			MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),

			(LPTSTR)&lpMsgBuf,

			0, NULL);

		MessageBox(NULL, (LPCTSTR)lpMsgBuf, L"Error", MB_OK | MB_ICONERROR);

		LocalFree(lpMsgBuf);

	}

	MSG msg = { };

	while (GetMessage(&msg, NULL, 0, 0))

	{

		TranslateMessage(&msg);

		DispatchMessage(&msg);

	}

	return 0;

}

Thank you.

Jeanine

---

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Answer 2

Give this code a try -

#include <Windows.h>
#include <Richedit.h>
#include <tchar.h>
WNDPROC oldStaticProc;
WNDPROC oldGreenProc;
int WINAPI _tWinMain(HINSTANCE, HINSTANCE, PTSTR, int);
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK StaticProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT CALLBACK GreenPanelProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
HINSTANCE g_hInstance;
int width = 800;
int height = 600;
#if _DEBUG
#pragma comment( linker, "/subsystem:console" )
int _tmain(int argc, const TCHAR** argv) {
    return _tWinMain(GetModuleHandle(NULL), NULL, GetCommandLine(), SW_SHOWDEFAULT);
}
#else
#pragma comment( linker, "/subsystem:windows" )
#endif
#pragma comment(lib, "opengl32.lib")
int WINAPI _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PTSTR szCmdLine, int iCmdShow) {
    g_hInstance = hInstance;
    HMODULE hMod = LoadLibrary(TEXT("Msftedit.dll"));
    if (!hMod)
    {
        // Handle the error
        MessageBox(NULL, TEXT("Failed to load Msftedit.dll"), TEXT("Error"), MB_OK | MB_ICONERROR);
        return 1; // Or some other error handling
    }
    WNDCLASS wc = { };
    LPCTSTR CLASS_NAME = TEXT("OpenGL and RichEdit Message Processing");
    wc.lpfnWndProc = WindowProcedure;
    wc.hInstance = hInstance;
    wc.lpszClassName = CLASS_NAME;
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    if (!RegisterClass(&wc))
    {
        MessageBox(NULL, TEXT("Window Registration Failed!"), TEXT("Error!"), MB_ICONEXCLAMATION | MB_OK);
        return 1;
    }
    WNDCLASS wcStatic = { };
    GetClassInfo(NULL, TEXT("STATIC"), &wcStatic);
    oldStaticProc = wcStatic.lpfnWndProc;
    wcStatic.lpfnWndProc = StaticProc;
    wcStatic.lpszClassName = TEXT("STATIC_SUBCLASS");
    if (!RegisterClass(&wcStatic))
    {
        MessageBox(NULL, TEXT("STATIC_SUBCLASS Registration Failed!"), TEXT("Error!"), MB_ICONEXCLAMATION | MB_OK);
        return 1;
    }
    WNDCLASS wcGreen = { };
    GetClassInfo(NULL, TEXT("STATIC"), &wcGreen);
    oldGreenProc = wcGreen.lpfnWndProc;
    wcGreen.lpfnWndProc = GreenPanelProc;
    wcGreen.lpszClassName = TEXT("GREEN_SUBCLASS");
    if (!RegisterClass(&wcGreen))
    {
        MessageBox(NULL, TEXT("GREEN_SUBCLASS Registration Failed!"), TEXT("Error!"), MB_ICONEXCLAMATION | MB_OK);
        return 1;
    }
    HWND hwnd = CreateWindowEx(
        0,
        CLASS_NAME,
        TEXT("OpenGL RichEdit Control"),
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT, width, height,
        NULL,
        NULL,
        hInstance,
        NULL
    );
    if (hwnd == NULL)
    {
        MessageBox(NULL, TEXT("Window Creation Failed!"), TEXT("Error!"), MB_ICONEXCLAMATION | MB_OK);
        return 1;
    }
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
    MSG msg = { };
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return 0;
}
LRESULT CALLBACK WindowProcedure(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    static HWND hwnd_green_panel = NULL, hwnd_richedit_panel = NULL;
    switch (msg)
    {
    case WM_CREATE:
    {
        RECT rc;
        GetClientRect(hwnd, &rc);
        hwnd_green_panel = CreateWindowEx(
            0,
            TEXT("GREEN_SUBCLASS"),
            NULL,
            WS_CHILD | WS_VISIBLE,
            0, 0, rc.right, rc.bottom - 150,
            hwnd,
            NULL,
            g_hInstance,
            NULL
        );
        hwnd_richedit_panel = CreateWindowEx(
            0,
            TEXT("STATIC_SUBCLASS"),
            NULL,
            WS_CHILD | WS_VISIBLE,
            0, rc.bottom - 150, rc.right, 150,
            hwnd,
            NULL,
            g_hInstance,
            NULL
        );
        if (!hwnd_green_panel || !hwnd_richedit_panel)
            return -1;
    }
    break;
    case WM_SIZE:
    {
        RECT rc;
        GetClientRect(hwnd, &rc);
        MoveWindow(hwnd_richedit_panel, 0, rc.bottom - 150, rc.right, 150, TRUE);
        MoveWindow(hwnd_green_panel, 0, 0, rc.right, rc.bottom - 150, TRUE);
    }
    break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hwnd, msg, wParam, lParam);
    }
    return 0;
}
LRESULT CALLBACK StaticProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    HPEN hPen = {}; HPEN hOldPen = {}; HDC hdc = {};
    switch (msg)
    {
    case WM_CREATE:
    {
        RECT rc;
        GetClientRect(hwnd, &rc);
        HWND richEdit = CreateWindowExW(
            WS_EX_CLIENTEDGE,
            MSFTEDIT_CLASS,
            L"Type here...",
            WS_CHILD | WS_VISIBLE | WS_VSCROLL | ES_MULTILINE | ES_AUTOVSCROLL,
            4, 4, rc.right - 8, rc.bottom - 8,  // Leave room for the red border
            hwnd,
            NULL,
            g_hInstance,
            NULL
        );
        if (!richEdit)
            return -1;
        LRESULT result = SendMessage(richEdit, WM_SETTEXT, 0, (LPARAM) TEXT("Hello, World!"));
        SendMessage(richEdit, EM_SETSEL, 0, 0);
        SendMessage(richEdit, EM_SCROLLCARET, 0, 0);
    }
    break;
    case WM_ERASEBKGND:
    {
        HDC hdc = (HDC)wParam;
        RECT rect;
        GetClientRect(hwnd, &rect);
        FillRect(hdc, &rect, (HBRUSH) GetStockObject(GRAY_BRUSH));
        return TRUE;
    }
    case WM_PAINT:
        PAINTSTRUCT ps;
        hdc = BeginPaint(hwnd, &ps);
        // Create a rectangle that is slightly smaller than the panel
        RECT rect;
        GetClientRect(hwnd, &rect);
        InflateRect(&rect, -2, -2);
        // Create a pen (for drawing lines) that is red and 2 pixels wide
        hPen = CreatePen(PS_SOLID, 2, RGB(255, 0, 0));
        // Select the pen into the device context
        hOldPen = (HPEN)SelectObject(hdc, hPen);
        // Draw a rectangle that is the same size as the panel
        Rectangle(hdc, rect.left, rect.top, rect.right, rect.bottom);
        // Clean up: deselect the pen, delete it, and end the paint operation
        SelectObject(hdc, hOldPen);
        DeleteObject(hPen);
        EndPaint(hwnd, &ps);
        break;
    default:
        return CallWindowProc(oldStaticProc, hwnd, msg, wParam, lParam);
    }
    return 0;
}
LRESULT CALLBACK GreenPanelProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    HPEN hPen = {}; HPEN hOldPen = {}; HDC hdc = {};
    switch (msg)
    {
    case WM_ERASEBKGND:
        return TRUE;
    case WM_PAINT:
        PAINTSTRUCT ps;
        hdc = BeginPaint(hwnd, &ps);
        // Create a rectangle that is slightly smaller than the panel
        RECT rect;
        GetClientRect(hwnd, &rect);
        InflateRect(&rect, -2, -2);
        // Create a pen (for drawing lines) that is green and 2 pixels wide
        hPen = CreatePen(PS_SOLID, 2, RGB(0, 255, 0));
        // Select the pen into the device context
        hOldPen = (HPEN)SelectObject(hdc, hPen);
        // Draw a rectangle that is the same size as the panel
        Rectangle(hdc, rect.left, rect.top, rect.right, rect.bottom);
        // Clean up: deselect the pen, delete it, and end the paint operation
        SelectObject(hdc, hOldPen);
        DeleteObject(hPen);
        EndPaint(hwnd, &ps);
        break;
    default:
        return CallWindowProc(oldGreenProc, hwnd, msg, wParam, lParam);
    }
    return 0;
}