在QT应用程序中使用win32的窗体

http://blog.csdn.net/tingsking18/archive/2009/11/07/4781619.aspx

首先要从QT的网站下载qtwinmigrate-2.8-opensource.zip，然后从QWinHost继承一个类

class HostWindow : public QWinHost
{
    Q_OBJECT
public:
    HostWindow(QWidget *parent = 0, Qt::WFlags f = 0)
        : QWinHost(parent, f)
    {
        setFocusPolicy(Qt::StrongFocus);
    }

    HWND createWindow(HWND parent, HINSTANCE instance)
    {
        static ATOM windowClass = 0;
        if (!windowClass)
        {
            WNDCLASSEX wcex;

            wcex.cbSize     = sizeof(WNDCLASSEX);
            wcex.style      = CS_HREDRAW | CS_VREDRAW;
            wcex.lpfnWndProc    = (WNDPROC)WndProc;
            wcex.cbClsExtra = 0;
            wcex.cbWndExtra = 0;
            wcex.hInstance  = instance;
            wcex.hIcon      = NULL;
            wcex.hCursor    = LoadCursor(NULL, IDC_ARROW);
            wcex.hbrBackground  = (HBRUSH)(COLOR_WINDOW+1);
            wcex.lpszMenuName   = NULL;
            wcex.lpszClassName  = L"qtest";
            wcex.hIconSm    = NULL;

            windowClass = RegisterClassEx(&wcex);
        }

        HWND hwnd = CreateWindow((TCHAR*)windowClass, 0, WS_CHILD|WS_CLIPSIBLINGS|WS_TABSTOP,
            CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, parent, NULL, instance, NULL);
        return hwnd;
    }

signals:
    void message(const QString &msg, int timeout);

public slots:
    void returnPressed()
    {
        QMessageBox::information(topLevelWidget(), "Message from Qt", "Return pressed in QLineEdit!");
    }

protected:
    static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
    {
        QWidget *widget = QWidget::find(GetParent(hWnd));
        HostWindow *window = qobject_cast(widget);

        if (window) switch (message)
        {

            case WM_LBUTTONDOWN:
                window->message("clicked", 1000);
                break;
            case WM_SETFOCUS:
                window->message("SetFocus for Win32 window!", 1000);
                break;
            case WM_KILLFOCUS:
                window->message("KillFocus for Win32 window!", 1000);
                break;
            case WM_MOUSEMOVE:
                window->message("Moving the mouse, aren't we?", 200);
                break;
            case WM_KEYDOWN:
                if (wParam != VK_TAB)
                    window->message("Key Pressed!", 500);
                break;
            default:
                return DefWindowProc(hWnd, message, wParam, lParam);
        }
        return 0;
    }
};

class HostWindow : public QWinHost { Q_OBJECT public: HostWindow(QWidget *parent = 0, Qt::WFlags f = 0) : QWinHost(parent, f) { setFocusPolicy(Qt::StrongFocus); } HWND createWindow(HWND parent, HINSTANCE instance) { static ATOM windowClass = 0; if (!windowClass) { WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = (WNDPROC)WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = instance; wcex.hIcon = NULL; wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = NULL; wcex.lpszClassName = L"qtest"; wcex.hIconSm = NULL; windowClass = RegisterClassEx(&wcex); } HWND hwnd = CreateWindow((TCHAR*)windowClass, 0, WS_CHILD|WS_CLIPSIBLINGS|WS_TABSTOP, CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, parent, NULL, instance, NULL); return hwnd; } signals: void message(const QString &msg, int timeout); public slots: void returnPressed() { QMessageBox::information(topLevelWidget(), "Message from Qt", "Return pressed in QLineEdit!"); } protected: static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { QWidget *widget = QWidget::find(GetParent(hWnd)); HostWindow *window = qobject_cast<HostWindow*>(widget); if (window) switch (message) { case WM_LBUTTONDOWN: window->message("clicked", 1000); break; case WM_SETFOCUS: window->message("SetFocus for Win32 window!", 1000); break; case WM_KILLFOCUS: window->message("KillFocus for Win32 window!", 1000); break; case WM_MOUSEMOVE: window->message("Moving the mouse, aren't we?", 200); break; case WM_KEYDOWN: if (wParam != VK_TAB) window->message("Key Pressed!", 500); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } return 0; } };

 

解释一下上面的HostWindow类，

1.    HostWindow类继承了QWinHost并且实现了在QWinHost中定义的虚函数createWindow()，createWindow()调用API函数RegisterClassEx注册窗口类。然后再调用Windows的API函数CreateWindow来创建窗口。

2.   下面的signals和slots都很简单。singals是给status发出显示信息的信号；slots是QLineEdit的确认信息。

3.   WndProc函数也很简单，是RegisterClassEx的回调函数。用来处理windows消息的。

注意：

由于WndProc是static的，所以我们可以使用QWidget::find来将HWND转换为QWidget。

处理消息的时候要使用QWinHost所以我们通过qobject_cast将QWidget转换为HostWindow。

下面是调用方法：

#include "main.moc"

 int main(int argc, char **argv)
 {
     QApplication a(argc, argv);

     QMainWindow mw;
     mw.menuBar()->addMenu("&File")->addAction("&Exit", &a, SLOT(quit()));

     QWidget central(&mw);

     QLineEdit edit(¢ral);
     HostWindow host(¢ral);
     QObject::connect(&host, SIGNAL(message(const QString&,int)), mw.statusBar(), SLOT(showMessage(const QString&,int)));
     QObject::connect(&edit, SIGNAL(returnPressed()), &host, SLOT(returnPressed()));

     QVBoxLayout vbox(¢ral);
     vbox.addWidget(&edit);
     vbox.addWidget(&host);

     mw.setCentralWidget(¢ral);
     mw.show();
     return a.exec();
 }

#include "main.moc" int main(int argc, char **argv) { QApplication a(argc, argv); QMainWindow mw; mw.menuBar()->addMenu("&File")->addAction("&Exit", &a, SLOT(quit())); QWidget central(&mw); QLineEdit edit(¢ral); HostWindow host(¢ral); QObject::connect(&host, SIGNAL(message(const QString&,int)), mw.statusBar(), SLOT(showMessage(const QString&,int))); QObject::connect(&edit, SIGNAL(returnPressed()), &host, SLOT(returnPressed())); QVBoxLayout vbox(¢ral); vbox.addWidget(&edit); vbox.addWidget(&host); mw.setCentralWidget(¢ral); mw.show(); return a.exec(); }

 

 

 

大家要注意一点：

我们的class在.cpp文件中实现的时候，并且包含Q_OBJECT宏的时候。我们在使用的时候要#include "main.moc"

包含.moc文件。因为.moc文件是moc将Q_OBJECT宏展开后的结果。如果我们直接编译的话，编译器是不认识

Q_OBJECT宏的。