使用C ++ Win32 GUI在窗口中显示文本

Question

at first sorry for my english :)

I have a little problem.

I have a program written in C++ which parse JavaScript files in order to find some keywords.

I have a main window and a main menu, and when you click to menu->open folder, you need to select your folder. After this, i recover all the files in this folder to open it, read it in order to find my keyword. When everything is sone, i display the result in a childwindow. I wanted to add a popup displaying a text like "loading, please wait" but i have a little problem.

Here is my code :

// creating a "popup" display a text while loading
MainWindow::m_hwndResLoading = CreateWindow(   "edit",
    "",
    WS_VISIBLE|ES_MULTILINE|ES_READONLY|WS_OVERLAPPED,
    0,
    0,
    400,
    200,
    hwnd,
    NULL,
    NULL,
    NULL);

// creating my str, and asking my m_hwndLoading to display my text
string loading = "Chargement";
SetWindowText(MainWindow::m_hwndResLoading,TEXT(loading.c_str()));

MainWindow::projectPath = path;

// this function find every files in a specified directory which is source code file
getAllFile(path);

// creating my childwindow which will contain the result of the files parsing
MainWindow::m_hwndRes = CreateWindow(   "edit",
    "",
    WS_VISIBLE|WS_CHILD|WS_BORDER|
    WS_VSCROLL|WS_HSCROLL|ES_MULTILINE|
    ES_AUTOHSCROLL|ES_AUTOVSCROLL|ES_READONLY,
    0,
    0,
    1000,
    600,
    hwnd,
    NULL,
    NULL,
    NULL);

// create and instanciate my object
FileParser *fp;
fp = new FileParser();
string res = fp->init(files);

// close my loading "popup"
CloseWindow(MainWindow::m_hwndResLoading);

// display the result in my child window
SetWindowText(MainWindow::m_hwndRes,TEXT(res.c_str()));

when i run the application, when i open the new folder, my "popup window" is displaying, but without the loading text. when the parsing is done, everythin works well, the popup window is closed and the child window is filled with the result.

I saw that, if i comment this line :

CloseWindow(MainWindow::m_hwndResLoading);

the loading text is displayed in the same moment than the result.

Does anyone have a little idea to help me?

Thanks a lot

Answer 1

I believe the problem is missing (win32) message processing. I assume you ave a message processing loop (like TranslateMessage , DispatchMessage and the like) somewhere in your code?

I think your problem is that you don't process messages (in this cases probably a REPAINT message) between the popup creation and your long loading routine. That's why your popup doesn't paint and the application freezes. Try to insert message processing calls between CreateWindow and FileParser::init .