_GRAPHICAL DATA VISULAIZATION_
by Marian G. Williams and Peter D. Varhol

EXAMPLE 1.  

(a)

EndEdit(  void  ) 
{
  int   index    = int(textString);
  int   newValue = this=>(textString);
 
  Erase(0);
  if (newValue >= 0) {
    chartData[index]   = newValue;
    this=>(textString) = newValue;
    }
  else {
    this=>(textString) = chartData[index];
    NoticeBox("Range Check Error", 
              "Data must be larger than zero.", 0);     
    }
  Draw(0);
  }


(b)

MenuCommand(  short id  ) {
  string      pageName;
  VZ_PAGEWINDOW** window;
  VZ_PAGE*    page;

  switch(id) {
     case 100:
    pageName = "faces 1";
    window  = &mdiChild1;
        break;  
     case 200:
    pageName = "faces 2";
    window   = &mdiChild2;
        break;
     case 300:
    pageName = "faces 3";
    window   = &mdiChild3;
        break;
     }

  if (!(*window) && (page = FindPage(pageName))) {
    *window = new VZ_PAGEWINDOW(page);
    if (*window) {
      (*window)->Show();
      }
    }
  }