Programming guideline of WinDom

''Ideal'' windows

The ''ideale'' windows changes the sliders size and position depending on their workspace size as the GEM desktop does. With the GEM desktop example, the number of icons per line displayed in a window depends on the window width, i.e. the variable xpos_max depends on the window width. So when the window gets a new size (with WM_SIZED and WM_FULLED messages) the variable xpos_max must be refreshed and the function WindSlider() called. That means that the functions attached to WM_SIZED and WM_FULLED should be customized:

    void ideal_szd( WINDOW *win) {
        void std_szd( WINDOW *);

        win->xpos_max = <new value>;
        win->xpos = <new value>;
        /* a new value for xpos_max implies a new value for ypos_max */
        win->ypos_max = <new value>;
        win->ypos = <new value>;
        std_szd( win);      /* do not invent the wheel ! */
    }

without forgeting to attach this function to the window with something like:

    EvntAttach( win, WM_SIZED, ideal_szd);

As you can see, the Windom intern managing of sliders is robust: you just have to write two functions and use the standard functions. Have a look at these standard functions std_szd() and std_fld() in the source code (file STDCODE.C). These functions are quite complex because they support three kind of situation.