--******************************************************************************
--*                                                                            *
--*  File:        TkLua_01.lua                          Revision:  1.0         *
--*                                                                            *
--*  Contents:    a simple system color display                                *
--*                                                                            *
--*  Creation:    06.03.2002                   Last Modification:  06.03.2002  *
--*                                                                            *
--*  Platform:    IBM-compatible PC running Windows 98SE                       *
--*                                                                            *
--*  Environment: Lua 4.0, TkLua 4.0                                           *
--*                                                                            *
--*  Author:      Andreas Rozek           Phone:  ++49 (711) 6770682           *
--*               Kirschblütenweg 15      Fax:    -                            *
--*             D-70569 Stuttgart         EMail:  Andreas.Rozek@T-Online.De    *
--*               Germany                                                      *
--*                                                                            *
--*  URL:         http://www.Andreas-Rozek.de/                                 *
--*                                                                            *
--*  Copyright:   the software is published under the "GNU Lesser General Pub- *
--*               lic  License" (see "http://www.fsf.org/copyleft/lesser.html" *
--*               for additional information)                                  *
--*                                                                            *
--*  Comments:    (none)                                                       *
--*                                                                            *
--******************************************************************************

  dofile("Lua_02_Lib.lua");     -- provides an extended 'tostring' function etc.
  dofile("TkLua_00_Lib.lua");    -- provides a simple console for TkLua programs

  local Icon     = "./Lua.gif";-- specifying the file name is already sufficient
  local Title    = "TkLua_01";
  local Subtitle = "a simple system color display";
        Status   = "click on a color to see its RGB definition";

  ColorList = {
    "SystemActiveBorder",   "SystemActiveCaption",   "SystemAppWorkspace",
    "SystemBackground",     "SystemButtonFace",      "SystemButtonHighlight",
    "SystemButtonShadow",   "SystemButtonText",      "SystemCaptionText",
    "SystemDisabledText",   "SystemHighlight",       "SystemHighlightText",
    "SystemInactiveBorder", "SystemInactiveCaption", "SystemInactiveCaptionText",
    "SystemMenu",           "SystemMenuText",        "SystemScrollbar",
    "SystemWindow",         "SystemWindowFrame",     "SystemWindowText"
  };

--******************************************************************************
--*                                                                            *
--* ColorSpec    retrieves RGB (background) color definition of a given widget *
--*                                                                            *
--******************************************************************************

  function ColorSpec (Widget)
    local Definition = tkeval("winfo rgb",Widget.tkname,Widget.background);
    return floor(Definition[1]/256)..","..floor(Definition[2]/256)..","..floor(Definition[3]/256);
  end;

--******************************************************************************
--*                                                                            *
--*                                main program                                *
--*                                                                            *
--******************************************************************************

--**** define window components ****

  local IconLabel      = tklabel{image=Icon, anchor="center", width=32, height=32};
  local TitleLabel     = tklabel{Title;      anchor="e", font="-*-helvetica-bold-o-*--16"};
  local SubtitleLabel  = tklabel{Subtitle;   anchor="e", font="-*-helvetica-bold-r-*--12"};
  local UpperSeparator = tkframe{relief="sunken", borderwidth=2,        height=2};

  local ViewList = {};                         -- receives a list of color views
  local Index, Column = 1,0;
    for Index = 1,getn(ColorList) do
      Column = Column + 1;

      tinsert(ViewList, tkframe{
        tklabel{ColorList[Index]},
          {side="left", anchor="e", fill="x", expand=1},
        tkframe{relief="sunken", borderwidth=1, width=16, height=16, background=ColorList[Index], ColorName=ColorList[Index]},
          {side="left", anchor="w", padx=1};
      });
        ViewList[ViewList.n][3]:bind(    -- bind some events to the color square
          "<Enter>", "StatusBar.text=self.ColorName"
        );
        ViewList[ViewList.n][3]:bind(
          "<Leave>", "StatusBar.text=Status"
        );
        ViewList[ViewList.n][3]:bind(
          "<ButtonPress-1>",
          "StatusBar.text=self.ColorName..' ('..ColorSpec(self)..')'"
        );
--    tinsert(ViewList, {sticky="e"});                  -- doesn't seem to work!

      if (Column == 3) then
        tinsert(ViewList, "/");                               -- start a new row
        Column = 0;
      end;
    end;
  local ColorView = tkframe{objects=ViewList, borderwidth=0, geoman="grid"};

  local LowerSeparator = tkframe{relief="sunken", borderwidth=2, height=2};
        StatusBar      = tklabel{Status; anchor="w", font="-*-helvetica-medium-r-*--11"};

--**** construct application window ****

  local MainWindow = tkmain{
    tkframe{
      IconLabel,     {side="left"},
      TitleLabel,    {side="top", fill="x"},
      SubtitleLabel, {side="top", fill="x"}
    },               {side="top", fill="x"},
    UpperSeparator,  {side="top", fill="x"},
    ColorView,       {side="top", fill="both", expand=1, pady=2},
    LowerSeparator,  {side="top", fill="x"},
    StatusBar,       {side="top", fill="x"}
  };

--**** display application window ****

  MainWindow:title(Title.." - "..Subtitle);
  MainWindow:show();                            -- also triggers a window layout
--MainWindow:resizable(0,0);                     -- disables window size changes
--MainWindow:raise();                   -- brings the window into the foreground

--**** it's now time to fine-tune the display ****

  for i = 1,getn(ViewList) do
    local tkname = ViewList[i].tkname;
    if (tkname ~= nil) then                   -- take care of layout descriptors
      tkeval('grid configure '..ViewList[i].tkname..' -sticky "e"');
    end;
  end;

--**** provide an explicit method to terminate this program! ****

  MainWindow:protocol("WM_DELETE_WINDOW", "print('done...'); tkexit()");