rosapps/taskmgr/proclist.c

   1 /*
   2  *  ReactOS Task Manager
   3  *
   4  *  proclist.cpp
   5  *
   6  *  Copyright (C) 1999 - 2001  Brian Palmer  <brianp@reactos.org>
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #define WIN32_LEAN_AND_MEAN             // Exclude rarely-used stuff from Windows headers
  24 #include <windows.h>
  25 #include <commctrl.h>
  26 #include <stdlib.h>
  27 #include <malloc.h>
  28 #include <memory.h>
  29 #include <tchar.h>
  30 #include <process.h>
  31 #include <stdio.h>
  32
  33 #include "taskmgr.h"
  34 #include "procpage.h"
  35 #include "proclist.h"
  36 #include "perfdata.h"
  37
  38
  39 LRESULT CALLBACK        ProcessListWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
  40
  41 LONG                            OldProcessListWndProc;
  42
  43
  44 LRESULT CALLBACK ProcessListWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
  45 {
  46         HBRUSH  hbrBackground;
  47         RECT    rcItem;
  48         RECT    rcClip;
  49         HDC             hDC;
  50         int             DcSave;
  51
  52         switch (message)
  53         {
  54         case WM_ERASEBKGND:
  55
  56                 //
  57                 // The list control produces a nasty flicker
  58                 // when the user is resizing the window because
  59                 // it erases the background to white, then
  60                 // paints the list items over it.
  61                 //
  62                 // We will clip the drawing so that it only
  63                 // erases the parts of the list control that
  64                 // show only the background.
  65                 //
  66
  67                 //
  68                 // Get the device context and save it's state
  69                 // to be restored after we're done
  70                 //
  71                 hDC = (HDC) wParam;
  72                 DcSave = SaveDC(hDC);
  73
  74                 //
  75                 // Get the background brush
  76                 //
  77                 hbrBackground = (HBRUSH) GetClassLong(hWnd, GCL_HBRBACKGROUND);
  78
  79                 //
  80                 // Calculate the clip rect by getting the RECT
  81                 // of the first and last items and adding them up.
  82                 //
  83                 // We also have to get the item's icon RECT and
  84                 // subtract it from our clip rect because we don't
  85                 // use icons in this list control.
  86                 //
  87                 ListView_GetItemRect(hWnd, 0, &rcClip, LVIR_BOUNDS);
  88                 ListView_GetItemRect(hWnd, ListView_GetItemCount(hWnd) - 1, &rcItem, LVIR_BOUNDS);
  89                 rcClip.bottom = rcItem.bottom;
  90                 ListView_GetItemRect(hWnd, 0, &rcItem, LVIR_ICON);
  91                 rcClip.left = rcItem.right;
  92
  93                 //
  94                 // Now exclude the clip rect
  95                 //
  96                 ExcludeClipRect(hDC, rcClip.left, rcClip.top, rcClip.right, rcClip.bottom);
  97
  98                 //
  99                 // Now erase the background
 100                 //
 101                 //
 102                 // FIXME: Should I erase it myself or
 103                 // pass down the updated HDC and let
 104                 // the default handler do it?
 105                 //
 106                 GetClientRect(hWnd, &rcItem);
 107                 FillRect(hDC, &rcItem, hbrBackground);
 108
 109                 //
 110                 // Now restore the DC state that we
 111                 // saved earlier
 112                 //
 113                 RestoreDC(hDC, DcSave);
 114
 115                 return TRUE;
 116         }
 117
 118         //
 119         // We pass on all messages except WM_ERASEBKGND
 120         //
 121         return CallWindowProc((WNDPROC)OldProcessListWndProc, hWnd, message, wParam, lParam);
 122 }