c ++ winapi不可能创建2个控件 [英] c++ winapi impossible to create 2 controls

问题描述

我正在尝试创建包含richedit控件和列表框控件的窗口，
的问题是，我创建的第二个控件，不显示。
我的意思是：

I'm trying to create window that contain richedit control and listbox control, the problem is that the second control which I create, doesn't show up. I mean:

case WM_CREATE: // In main window procedure
{
    /* Center the main window */
    This->CenterWindow(hwnd);

    /* Initialize the clients list */
    This->InitListClients(hwnd);

    /* Initialize the server log */
    This->InitEditLog(hwnd);

    return 0;
}

如果 InitListClients 函数将首先，只有列表框将显示，
如果 InitEditLog 将是第一，只有richedit会显示。

If InitListClients function will be first, only the listbox will show up, if InitEditLog will be first, only the richedit will show up.

这里是函数：

void ApostleServer::InitEditLog(HWND &_hwnd)
{
    LoadLibrary(TEXT("Riched32.dll"));
    hEditLog = CreateWindowEx(WS_EX_STATICEDGE, "richedit", "bla", WS_CHILD | WS_VISIBLE | ES_MULTILINE, 10, 10, 390, 310, _hwnd, NULL, (HINSTANCE)GetWindowLong(_hwnd, GWL_HINSTANCE), NULL);
}

void ApostleServer::InitListClients(HWND &_hwnd)
{
    hListClients = CreateWindowEx(WS_EX_STATICEDGE, "listbox", "bla", WS_CHILD | WS_VISIBLE | LBS_NOTIFY, 550, 20, 150, 150, _hwnd, NULL, (HINSTANCE)GetWindowLong(_hwnd, GWL_HINSTANCE), NULL);
}

我有一个新手winapi和我找不到解决方案问题。
感谢。

I'm kinda newbie with winapi and I couldn't find solution for this problem. Thanks.

编辑：
正如我所说的，问题的原因是使用类成员。
这是一个我写的整个代码，并有同样的问题：

As I commented, the cause of the problem is the use of class members. Here is a whole code that I've wrote and has the same problem:

#include <Windows.h>
#include <stdlib.h>

class Server
{
public:

    /* Fields */
    MSG* msg;
    WNDCLASSW* wc;
    HWND hListClients;
    HWND hEditLog;

    /* Methods */
    void InitEditLog(HWND &_hwnd)
    {
        LoadLibrary(TEXT("Riched32.dll"));
        hEditLog = CreateWindowExW(WS_EX_STATICEDGE, L"richedit", L"Text", WS_CHILD | WS_VISIBLE | ES_MULTILINE, 10, 10, 390, 306, _hwnd, (HMENU)2, (HINSTANCE)GetWindowLong(_hwnd, GWL_HINSTANCE), NULL);
    }

    void InitListClients(HWND &_hwnd)
    {
        // Here I'm using hListClients class member, and that what cause the problem (I will see only the list on the window)
        hListClients = CreateWindowExW(WS_EX_STATICEDGE, L"listbox", L"asd", WS_CHILD | WS_VISIBLE | LBS_NOTIFY, 410, 10, 160, 306, _hwnd, (HMENU)1, (HINSTANCE)GetWindowLong(_hwnd, GWL_HINSTANCE), NULL);
        // If I was only creating the listbox (without returning handler), I will see the listbox and the richedit.
    }

    static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
    {

        Server* This = (Server*)GetWindowLongW(hwnd, GWL_USERDATA);

        switch(msg)
        {
            case WM_CREATE:
            {
                /* Initialize the clients list */
                This->InitListClients(hwnd); // Attention that I called this function first.

                /* Initialize the server log */
                This->InitEditLog(hwnd);
                // If I would call this function first, I will see only the richedit.

                return 0;
            }

            case WM_DESTROY:
            {
                PostQuitMessage(0);
                return 0;
            }
        }

        return DefWindowProcW(hwnd, msg, wParam, lParam);
    }

    Server(HINSTANCE &_hInstance)
    {
        msg = new MSG;
        wc = new WNDCLASSW;
        wc->style = CS_HREDRAW | CS_VREDRAW;
        wc->cbClsExtra = 0;
        wc->cbWndExtra = 0;
        wc->lpszClassName = L"ApostleServer";
        wc->hInstance = _hInstance;
        wc->hbrBackground = GetSysColorBrush(COLOR_3DFACE);
        wc->lpszMenuName = NULL;
        wc->lpfnWndProc = WndProc;
        wc->hCursor = LoadCursor(NULL, IDC_ARROW);
        wc->hIcon = LoadIcon(NULL, IDI_APPLICATION);

        RegisterClassW(&(*wc));
        CreateWindowW(wc->lpszClassName, L"Apostle Server", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 100, 100, 600, 400, 0, 0, _hInstance, 0);

        while(GetMessage(&(*msg), NULL, 0, 0))
        {
            TranslateMessage(&(*msg));
            DispatchMessage(&(*msg));
        }

    }
};

int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)
{
    Server* srvr = new Server(hInstance);
    return 0;
}

推荐答案

通过创建控件on WM_CREATE 消息（但不设置控制处理程序！），并在创建主窗口后设置控制处理程序。

Problem solved by creating the controls on WM_CREATE message (but not to set control handlers!), and set the control handlers after the creation of the main window.

WM_CREATE 讯息：

    case WM_CREATE:
    {
        /* Center the main window */
        This->CenterWindow(hwnd);

        /* Initialize the clients list */
        This->InitListClients(hwnd);

        /* Initialize the server log */
        This->InitEditLog(hwnd);


        return 0;
    }

创建主窗口后：

RegisterClassW(&(*wc));
hMainWindow = CreateWindowW(wc->lpszClassName, L"Apostle Server", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 100, 100, 600, 400, 0, 0, _hInstance, 0);

/* Set controls handlers */
hListClients = GetDlgItem(hMainWindow, IDC_LISTCLIENTS);
hEditLog = GetDlgItem(hMainWindow, IDC_EDITLOG);

InitEditLog InitListClients 函数：

InitEditLog and InitListClients functions:

void ApostleServer::InitEditLog(HWND &_hwnd)
{
    LoadLibrary(TEXT("Riched32.dll"));
    CreateWindowExW(WS_EX_STATICEDGE, L"richedit", L"Text", WS_CHILD | WS_VISIBLE | ES_MULTILINE, 10, 10, 390, 306, _hwnd, (HMENU)IDC_EDITLOG, (HINSTANCE)GetWindowLong(_hwnd, GWL_HINSTANCE), NULL);
}

void ApostleServer::InitListClients(HWND &_hwnd)
{
    CreateWindowExW(WS_EX_STATICEDGE, L"listbox", L"asd", WS_CHILD | WS_VISIBLE | LBS_NOTIFY, 410, 10, 160, 306, _hwnd, (HMENU)IDC_LISTCLIENTS, (HINSTANCE)GetWindowLong(_hwnd, GWL_HINSTANCE), NULL);
}

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