// Author: Roel Aaij 21/07/2007

/*************************************************************************
 * Copyright (C) 1995-2007, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

#include "TGCanvas.h"
#include "TGFrame.h"
#include "TClass.h"
#include "TGWindow.h"
#include "TGResourcePool.h"
#include "Riostream.h"
#include "TSystem.h"
#include "TImage.h"
#include "TEnv.h"
#include "TGToolTip.h"
#include "TGWidget.h"
#include "TGPicture.h"
#include "TRandom3.h"
#include "TVirtualTableInterface.h"
#include "TGTable.h"
#include "TGTableCell.h"
#include "TGTableHeader.h"
#include "TObjArray.h"
#include "TGTableContainer.h"
#include "TGScrollBar.h"
#include "TGButton.h"
#include "TGNumberEntry.h"
#include "TGTextEntry.h"
#include "TGLabel.h"
#include "TColor.h"

ClassImp(TGTable)
ClassImp(TTableRange)

//______________________________________________________________________________
/* Begin_Html
<center><h2>TGTable</h2></center>
<br><br>                                                                    
TGTable implements a table widget to display data in rows and       
columns. The data is supplied by a TVirtualTableInterface.          
<br><br>
The table is a TGCanvas to make use of already available viewport   
functionality and drawing optimizations.                            
<br><br>
The top left cell in a table has coordinates (0,0)                  
<br><br>
A TObjArray is used internally to ensure little overhead and fast   
acces to cells.                                                     
<br><br>
If the data source has more rows than the default 50 rows of cells in
memory, buttons at the bottom of the table can be used to load the
next or previous chunk of data.
<br><br>
At the top of the table, a frame is visible that shows the coordinates
of the top left cell currently in memmory in row,column. The amount of
rows and columns is also shown in rows x columns. These values can be
edited to move to a different area of the data source or to resize the
table. Tab will switch between the enties, return will move to the
currently entered range and resize the table if needed. Clicking the
goto button has the same effect.
<br><br>
A TGTable is created by first creating an appropriate               
TVirtualTableInterface from the data that needs visualization and   
then creating the TGTable using this interface.                     
<br><br>
A simple macro to use a TGTable with a TGSimpleTableInterface:
End_Html
Begin_Macro(source, gui)
{
   // Create an array to hold a bunch of numbers
   Int_t i = 0, j = 0;
   UInt_t nrows = 6, ncolumns = 5;
   Double_t** data = new Double_t*[nrows];
   for (i = 0; i < nrows; i++) {
      data[i] = new Double_t[ncolumns];
      for (j = 0; j < ncolumns; j++) {
         data[i][j] = 10 * i + j;
      }
   }

   // Create a main frame to contain the table
   TGMainFrame* mainframe = new TGMainFrame(0, 400, 200);
   mainframe->SetCleanup(kDeepCleanup) ;

   // Create an interface
   TGSimpleTableInterface *iface = new TGSimpleTableInterface(data, 6, 5); 

   // Create the table
   TGTable *table = new TGTable(mainframe, 999, iface); 

   // Add the table to the main frame
   mainframe->AddFrame(table, new TGLayoutHints(kLHintsExpandX | kLHintsExpandY));

   //Update data
   data[5][1] = 3.01; 
   //update the table view
   table->Update(); 

   // Layout and map the main frame
   mainframe->SetWindowName("Tree Table Test") ;
   mainframe->MapSubwindows() ;
   mainframe->Layout();
   mainframe->Resize() ;
   mainframe->MapWindow() ;

   return mainframe;
}
End_Macro
Begin_Html

It is also possible to visualise data from a tree. A simple macro
showing the use of a TTreeTableInterface follows.
End_Html
Begin_Macro(source, gui)
{
   // Open a root file.
   TFile *file = new TFile("$ROOTSYS/tutorials/hsimple.root");
   // Load a tree from the file
   TNtuple *ntuple = (TNtuple *)file.Get("ntuple");

   // Create an interface
   TTreeTableInterface *iface = new TTreeTableInterface(ntuple); 

   // Create a main frame to contain the table
   TGMainFrame* mainframe = new TGMainFrame(0, 400, 200);
   mainframe->SetCleanup(kDeepCleanup) ;

   // Create the table
   TGTable *table = new TGTable(mainframe, 999, iface, 10, 6); 

   // Add the table to the main frame
   mainframe->AddFrame(table, new TGLayoutHints(kLHintsExpandX | kLHintsExpandY));

   // Set a selection
   iface->SetSelection("px > 0.");
   // Add a column
   iface->AddColumn("(px+py)/(px-py)", 0);
   //update the table view
   table->Update(); 

   // Layout and map the main frame
   mainframe->SetWindowName("Tree Table Test") ;
   mainframe->MapSubwindows() ;
   mainframe->Layout();
   mainframe->Resize() ;
   mainframe->MapWindow() ;

   return mainframe;
}
End_Macro
*/

// const TGGC *TGTable::fgDefaultSelectGC = 0;
// const TGGC *TGTable::fgDefaultBckgndGC = 0;
// const Int_t TGTable::fgDefaultTMode = kTextLeft | kTextTop;

// TList *TGTable::fgEditList = 0 ;

//______________________________________________________________________________
TGTable::TGTable(const TGWindow *p, Int_t id, TVirtualTableInterface *interface, 
                 UInt_t nrows, UInt_t ncolumns) 
   : TGCompositeFrame(p, 500, 500, kVerticalFrame), TGWidget(id), fRows(0), 
     fRowHeaders(0), fColumnHeaders(0), fReadOnly(kFALSE), fSelectColor(0), 
     fTMode(0), fAllData(kFALSE), fTableFrame(0), fCanvas(0), fCellWidth(80), 
     fCellHeight(25), fInterface(interface)
{
   // TGTable constuctor.

   fCurrentRange = new TTableRange();
   fDataRange = new TTableRange();
   fGotoRange = new TTableRange();
   TGLayoutHints *hints = 0;
   fCellHintsList = new TList(hints);
   fRHdrHintsList = new TList(hints);
   fCHdrHintsList = new TList(hints);
   fMainHintsList = new TList(hints);

   // To be done: GetBackground colors for .rootrc 
   SetBackgroundColor(GetWhitePixel());
   fEvenRowBackground = TColor::RGB2Pixel(204, 255, 204);
   fOddRowBackground  = TColor::RGB2Pixel(255, 255, 255);
   fHeaderBackground  = TColor::RGB2Pixel(204, 204, 255);

   fCurrentRange->fXbr = ncolumns;
   fCurrentRange->fYbr = nrows;

   Init();

   if(fInterface) SetInterface(fInterface, nrows, ncolumns);
   SetWindowName();
//    MapWindow();
}

//______________________________________________________________________________
TGTable::~TGTable()
{
   // TGTable destructor.

   // delete all cells in a good way
   UInt_t i = 0, j = 0;
   for (i = 0; i < GetNTableRows(); i++) {
      for (j = 0; j < GetNTableColumns(); j++) {
         delete GetCell(i,j);
      }
      delete fRows->At(i);
   }
   delete fRows;
   delete fRowHeaders;
   delete fColumnHeaders;

   delete fCurrentRange;
   delete fDataRange;
   delete fGotoRange;

   fCellHintsList->Delete();
   delete fCellHintsList;
   delete fRHdrHintsList;
   delete fCHdrHintsList;

   fMainHintsList->Delete();
   delete fMainHintsList;
}

//______________________________________________________________________________
void TGTable::Init() 
{
   // Initialise the TGTable.

   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();

   // Main layout frames
   fTopFrame = new TGHorizontalFrame(this, fWidth, fCellHeight);
   fTopExtraFrame = new TGHorizontalFrame(fTopFrame, fWidth - fCellWidth, 
                                          fCellHeight);
   TGString *str = new TGString();
   *str += GetNTableRows();
   *str += "x";
   *str += GetNTableColumns();
   *str += " Table";
   fTableHeader = new TGTableHeader(fTopFrame, this, str, 0, 
                                    kTableHeader);

   fBottomFrame = new TGHorizontalFrame(this, fWidth, fHeight - fCellHeight);
   fRHdrFrame = new TGTableHeaderFrame(fBottomFrame, this, fCellWidth, 
                                       fHeight - fCellHeight, kRowHeader);
   fCHdrFrame = new TGTableHeaderFrame(fTopExtraFrame, this, fWidth - fCellWidth, 
                                       fCellHeight, kColumnHeader);

   // Frame for the buttons at the bottom
   fButtonFrame = new TGHorizontalFrame(this, 200, 50);
   fNextButton = new TGTextButton(fButtonFrame, "Next", WidgetId() + 2000); 
   fPrevButton = new TGTextButton(fButtonFrame, "Previous", WidgetId() + 2001); 
   fUpdateButton = new TGTextButton(fButtonFrame, "Update", WidgetId() + 2002); 

   fCanvas = new TGCanvas(fBottomFrame, ncolumns * fCellWidth, 
                          nrows * fCellHeight, 0);
   fTableFrame = new TGTableFrame(fCanvas->GetViewPort(), nrows, ncolumns);
   fTableFrame->SetCanvas(fCanvas);
   fCanvas->SetContainer(fTableFrame->GetFrame());

   // Frame to display range info and goto button.
   fRangeFrame = new TGHorizontalFrame(this, 450, 50);
   fFirstCellLabel = new TGLabel(fRangeFrame, "Top left cell in range:");
   fRangeLabel = new TGLabel(fRangeFrame, "Range:");
   fFirstCellEntry = new TGTextEntry(fRangeFrame, "0,0", WidgetId() + 2050);
   fFirstCellEntry->SetWidth(100);
   fFirstCellEntry->SetAlignment(kTextRight);
   fFirstCellEntry->Connect("TextChanged(const char *)", "TGTable", this, 
                            "UserRangeChange()");
   fFirstCellEntry->Connect("ReturnPressed()", "TGTable", this, "Goto()");

   TString range;
   range += GetNTableRows();
   range += "x";
   range += GetNTableColumns();
   fRangeEntry = new TGTextEntry(range, fRangeFrame, WidgetId() + 2051);
   fRangeEntry->SetWidth(100);
   fRangeEntry->SetAlignment(kTextRight);
   fRangeEntry->Connect("TextChanged(const char *)", "TGTable", this,
                        "UserRangeChange()");
   fRangeEntry->Connect("ReturnPressed()", "TGTable", this, "Goto()");
   fRangeEntry->Connect("TabPressed()", "TGTextEntry", fFirstCellEntry, 
                            "SetFocus()");
   fFirstCellEntry->Connect("TabPressed()", "TGTextEntry", fRangeEntry, 
                            "SetFocus()");

   fGotoRange->fXbr = GetNTableRows();
   fGotoRange->fYbr = GetNTableColumns();
   fGotoButton = new TGTextButton(fRangeFrame, "Goto", WidgetId() + 2003); 
   fGotoButton->SetState(kButtonDisabled);
   
   // Set frame backgrounds
   fCHdrFrame->SetBackgroundColor(fBackground);
   fRHdrFrame->SetBackgroundColor(fBackground);
   fRangeFrame->SetBackgroundColor(fBackground);
   fTopFrame->SetBackgroundColor(fBackground);
   fTopExtraFrame->SetBackgroundColor(fBackground);
   fBottomFrame->SetBackgroundColor(fBackground);
   fButtonFrame->SetBackgroundColor(fBackground);
   fFirstCellLabel->SetBackgroundColor(fBackground);
   fRangeLabel->SetBackgroundColor(fBackground);

   // Create the cells needed
   UInt_t i = 0, j = 0;
   TGString *label = 0;
   fRowHeaders = new TObjArray(nrows);
   for(i = 0; i < nrows; i++) {
      TGTableHeader *hdr = new TGTableHeader(fRHdrFrame, this, 
                                             label, i, kRowHeader); 
      fRowHeaders->AddAt(hdr, i);
   }
   fColumnHeaders = new TObjArray(ncolumns);
   for(i = 0; i < ncolumns; i++) {
      TGTableHeader *hdr = new TGTableHeader(fCHdrFrame, this, 
                                             label, i, kColumnHeader);
      fColumnHeaders->AddAt(hdr, i);
   }

   TGTableCell *cell = 0;
   TObjArray *row = 0;
   fRows = new TObjArray(nrows);
   for (i = 0; i < nrows; i++) {
      row = new TObjArray(ncolumns);
      fRows->AddAt(row, i);
      for (j = 0; j < ncolumns; j++) {
         cell = new TGTableCell(fCanvas->GetContainer(), this, label, i, j);
         row->AddAt(cell, j);
      }
   }

   // Check if the table covers all the data
   if ((GetNDataColumns() >= GetNTableColumns()) && 
       (GetNDataRows() >= GetNTableRows())) {
      fAllData = kTRUE;
   } else {
      fAllData = kFALSE;
   }

   TGLayoutHints *lhints = 0;

   // Add cells and headers to layout frames
   for (i = 0; i < nrows; i++) {
      lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop);
      fRHdrHintsList->Add(lhints);
      fRHdrFrame->AddFrame(GetRowHeader(i), lhints);
      for (j = 0; j < ncolumns; j++) {
         if (i == 0) {
            lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop);
            fCHdrHintsList->Add(lhints);
            fCHdrFrame->AddFrame(GetColumnHeader(j), lhints);
         }
         lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop);
         fCellHintsList->Add(lhints);
         fCanvas->AddFrame(GetCell(i,j), lhints);
      }
   }
   
   // Add frames to the range frame
   lhints = new TGLayoutHints(kLHintsRight | kLHintsCenterY, 3, 30, 4, 4);
   fRangeFrame->AddFrame(fGotoButton, lhints);
   lhints = new TGLayoutHints(kLHintsRight |kLHintsCenterY, 3, 3, 4, 4);
   fRangeFrame->AddFrame(fRangeEntry, lhints);
   lhints = new TGLayoutHints(kLHintsRight |kLHintsCenterY, 3, 3, 4, 4);
   fRangeFrame->AddFrame(fRangeLabel, lhints);
   lhints = new TGLayoutHints(kLHintsRight |kLHintsCenterY, 3, 3, 4, 4);
   fRangeFrame->AddFrame(fFirstCellEntry, lhints);
   lhints = new TGLayoutHints(kLHintsRight |kLHintsCenterY, 3, 3, 4, 4);
   fRangeFrame->AddFrame(fFirstCellLabel, lhints);
   lhints = new TGLayoutHints(kLHintsRight |kLHintsTop);
   fRangeFrame->Resize();
   // Range frame size = 448
   AddFrame(fRangeFrame, lhints);

   // Add table to the main composite frame
   lhints = new TGLayoutHints(kLHintsLeft |kLHintsTop);
   fTopFrame->AddFrame(fTableHeader, lhints);
   lhints = new TGLayoutHints(kLHintsLeft | kLHintsExpandX | kLHintsTop);
   fTopExtraFrame->AddFrame(fCHdrFrame, lhints);
   lhints = new TGLayoutHints(kLHintsLeft | kLHintsExpandX | kLHintsTop);
   fTopFrame->AddFrame(fTopExtraFrame, lhints);
   lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop | kLHintsExpandY);
   fBottomFrame->AddFrame(fRHdrFrame, lhints);
   lhints =  new TGLayoutHints(kLHintsLeft | kLHintsTop | kLHintsExpandX 
                               | kLHintsExpandY);
   fBottomFrame->AddFrame(fCanvas, lhints);

   // Add buttons to button frame
   lhints = new TGLayoutHints(kLHintsRight | kLHintsCenterY, 3, 30, 4, 4);
   fButtonFrame->AddFrame(fNextButton, lhints);   
   lhints = new TGLayoutHints(kLHintsRight | kLHintsCenterY, 3, 3, 4, 4);
   fButtonFrame->AddFrame(fPrevButton, lhints);   
   lhints = new TGLayoutHints(kLHintsRight | kLHintsCenterY, 3, 30, 4, 4);
   fButtonFrame->AddFrame(fUpdateButton, lhints);
   fButtonFrame->Resize();
   fButtonFrame->ChangeOptions(fButtonFrame->GetOptions() | kFixedWidth);

   lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop | kLHintsExpandX);
   AddFrame(fTopFrame, lhints);
   lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop | kLHintsExpandX | 
                              kLHintsExpandY);
   AddFrame(fBottomFrame, lhints);
   lhints = new TGLayoutHints(kLHintsExpandX | kLHintsTop);
   AddFrame(fButtonFrame, lhints);

   // Setup scrolling for the headers
   TGScrollBar *sbar= fCanvas->GetVScrollbar();
   sbar->Connect("PositionChanged(Int_t)", "TGTable", this, "ScrollRHeaders(Int_t)");
   sbar = fCanvas->GetHScrollbar();
   sbar->Connect("PositionChanged(Int_t)", "TGTable", this, "ScrollCHeaders(Int_t)");

   // Connections for buttons
   fUpdateButton->Connect("Clicked()", "TGTable", this, "Update()");
   fNextButton->Connect("Clicked()", "TGTable", this, "NextChunk()");
   fPrevButton->Connect("Clicked()", "TGTable", this, "PreviousChunk()");
   fGotoButton->Connect("Clicked()", "TGTable", this, "Goto()");

//    MapSubwindows();
//    Layout();
}

//______________________________________________________________________________
void TGTable::DoRedraw()
{
   // Redraw the TGTable.

   MapSubwindows();
   Layout();
}

//______________________________________________________________________________
void TGTable::Expand(UInt_t nrows, UInt_t ncolumns) 
{
   // Expand a TGTable by nrows and ncolumns.

   ExpandRows(nrows);
   ExpandColumns(ncolumns);
}

//______________________________________________________________________________
void TGTable::ExpandColumns(UInt_t ncolumns) 
{
   // Expand the columns of a TGTable by ncolumns.

   UInt_t i = 0, j = 0;
   TGString *label = 0;

   UInt_t ntrows = GetNTableRows();
   UInt_t ntcolumns = GetNTableColumns();

   fColumnHeaders->Expand(ntcolumns + ncolumns);

   for (i = 0; i < ncolumns; i++) {
      TGTableHeader *header = new TGTableHeader(fCHdrFrame, this, label, 
                                                ntcolumns + i, 
                                                kColumnHeader);
      fColumnHeaders->AddAt(header, ntcolumns + i);
   }

   for (i = 0; i < ntrows; i++) {
      GetRow(i)->Expand(ntcolumns + ncolumns);
      for (j = 0; j < ncolumns; j++) {
         TGTableCell *cell = new TGTableCell(fCanvas->GetContainer(), this, label, i, 
                                             ntcolumns + j);
         GetRow(i)->AddAt(cell, ntcolumns + j);
      }
   }

   fCurrentRange->fXbr += ncolumns;

   if ((GetNDataColumns() == GetNTableColumns()) && 
       (GetNDataRows() == GetNTableRows())) {
      fAllData = kTRUE;
   } else {
      fAllData = kFALSE;
   }
}

//______________________________________________________________________________
void TGTable::ExpandRows(UInt_t nrows) 
{
   // Expand the rows of a TGTable by nrows.

   UInt_t i = 0, j = 0; 

   UInt_t ntrows = GetNTableRows();
   UInt_t ntcolumns = GetNTableColumns();

   fRows->Expand(ntrows + nrows);
   fRowHeaders->Expand(ntrows + nrows);
   for (i = 0; i < nrows; i++) {
      TObjArray *row = new TObjArray(ntcolumns);
      fRows->AddAt(row, ntrows + i);  
      TGString *label = 0;
      TGTableHeader *header = new TGTableHeader(fRHdrFrame, this, label, 
                                                ntrows + i, kRowHeader);
      fRowHeaders->AddAt(header, ntrows + i);
      for (j = 0; j < ntcolumns ; j++) {
         TGTableCell *cell = new TGTableCell(fCanvas->GetContainer(), this, label, 
                                             ntrows + i, j);
         GetRow(ntrows + i)->AddAt(cell, j);
      }
   }
   
   fCurrentRange->fYbr += nrows;

   if ((GetNDataColumns() == GetNTableColumns()) && 
       (GetNDataRows() == GetNTableRows())) {
      fAllData = kTRUE;
   } else {
      fAllData = kFALSE;
   }
}

//______________________________________________________________________________
UInt_t TGTable::GetCHdrWidth() const
{
   // Get the current width of the column header frame.

   Int_t ncolumns = GetNTableColumns();
   UInt_t width = 0;
   for (Int_t i = 0; i < ncolumns; i++) {
      width += GetColumnHeader(i)->GetWidth();
   }
   return width;
}

//______________________________________________________________________________
UInt_t TGTable::GetRHdrHeight() const
{
   // Get the current height of the row header frame.

   Int_t nrows = GetNTableRows();
   UInt_t height = 0;
   for (Int_t i = 0; i < nrows; i++) {
      height += GetRowHeader(i)->GetHeight();
   }
   return height;
}

//______________________________________________________________________________
void TGTable::Shrink(UInt_t nrows, UInt_t ncolumns) 
{
   // Shrink the TGTable by nrows and ncolumns.

   ShrinkRows(nrows);
   ShrinkColumns(ncolumns);
}

//______________________________________________________________________________
void TGTable::ShrinkColumns(UInt_t ncolumns) 
{
   // Shrink the columns of the TGTable by ncolumns.

   UInt_t i = 0, j = 0, k = 0;

   if(GetNTableColumns() - ncolumns < 1) {
      Info("TGTable::ShrinkColumns", "Cannot shrink smaller than 1"
                                     " column, adjusting");
      ncolumns = GetNTableColumns() - 1;
   }

   UInt_t ntrows = GetNTableRows();
   UInt_t ntcolumns = GetNTableColumns();

   TGTableCell *cell = 0;

   //Destroy windows

   for (i = 0; i < ntrows; i++) {
      for (j = 0; j < ncolumns; j++) {
         k = ntcolumns - ncolumns + j;
         cell = (TGTableCell *)GetRow(i)->RemoveAt(k);
         cell->DestroyWindow();
         delete cell;
      }
      GetRow(i)->Expand(ntcolumns - ncolumns);
   }

   TGTableHeader *hdr = 0;
   for (j = 0; j < ncolumns; j++) {
      hdr = (TGTableHeader *)fColumnHeaders->RemoveAt(ntcolumns - ncolumns + j);
      hdr->DestroyWindow();
      delete hdr;
   }
   fColumnHeaders->Expand(ntcolumns - ncolumns);

   fCurrentRange->fXbr -= ncolumns;


   if ((GetNDataColumns() == GetNTableColumns()) && 
       (GetNDataRows() == GetNTableRows())) {
      fAllData = kTRUE;
   } else {
      fAllData = kFALSE;
   }
}

//______________________________________________________________________________
void TGTable::ShrinkRows(UInt_t nrows) 
{
   // Shrink the rows of the TGTable by nrows.

   UInt_t i = 0 , j = 0;

   if(GetNTableRows() - nrows < 1) {
      Info("TGTable::ShrinkRows", "Cannot shrink smaller than 1 row, adjusting");
      nrows = GetNTableRows() - 1;
   }

   UInt_t ntrows = GetNTableRows();
   UInt_t ntcolumns = GetNTableColumns();

   TObjArray *row = 0;
   TGTableCell *cell = 0;
   TGTableHeader *hdr = 0;

   for (i = 0; i < nrows; i++) {
      for (j = 0; j < ntcolumns ; j++) {
         cell = (TGTableCell *)GetRow(ntrows - nrows + i)->RemoveAt(j);
         cell->DestroyWindow();
         delete cell;
      }
      row = (TObjArray *)fRows->RemoveAt(ntrows - nrows + i);
      delete row;
      hdr = (TGTableHeader *)fRowHeaders->RemoveAt(ntrows - nrows + i);
      hdr->DestroyWindow();
      delete hdr;
   }
   fRows->Expand(ntrows - nrows);
   fRowHeaders->Expand(ntrows - nrows);

   fCurrentRange->fYbr -= nrows;

   if ((GetNDataColumns() == GetNTableColumns()) && 
       (GetNDataRows() == GetNTableRows())) {
      fAllData = kTRUE;
   } else {
      fAllData = kFALSE;
   }
}

//______________________________________________________________________________
void TGTable::UpdateHeaders(EHeaderType type)
{
   // Update the labels of the headers of the given type

   UInt_t max = 0, i = 0, d = 0;
   if(type == kColumnHeader) {
      max = GetNTableColumns();
      for (i = 0; i < max; i++) {
         d = fCurrentRange->fXtl + i;
         GetColumnHeader(i)->SetLabel(fInterface->GetColumnHeader(d));
      }
   } else if (type == kRowHeader) {
      max = GetNTableRows();
      for (i = 0; i < max; i++) {
         d = fCurrentRange->fYtl + i;
         GetRowHeader(i)->SetLabel(fInterface->GetRowHeader(d));
      }
   }
}

//______________________________________________________________________________
void TGTable::SetInterface(TVirtualTableInterface *interface, 
                           UInt_t nrows, UInt_t ncolumns)
{
   // Set the interface that the TGTable uses to interface.

   fInterface = interface;

   // Set up ranges

   fDataRange->fXtl = 0;
   fDataRange->fYtl = 0;
   fDataRange->fXbr = fInterface->GetNColumns();
   fDataRange->fYbr = fInterface->GetNRows();

   UInt_t x = 0, y = 0;
   if (fDataRange->fXbr < ncolumns) {
      x = fDataRange->fXbr;
   } else {
      x = ncolumns;
   }

   if (fDataRange->fYbr < nrows) {
      y = fDataRange->fYbr;
   } else {
      y = nrows;
   }

   GotoTableRange(0, 0, x, y);

   if ((GetNDataColumns() == GetNTableColumns()) && 
       (GetNDataRows() == GetNTableRows())) {
      fAllData = kTRUE;
   } else {
      fAllData = kFALSE;
   }
}

//______________________________________________________________________________
void TGTable::ResizeTable(UInt_t newnrows, UInt_t newncolumns)
{
   // Resize the table to newnrows and newncolumns and add all the frames to 
   // their parent frames.

   UInt_t oldnrows = GetNTableRows();
   UInt_t oldncolumns = GetNTableColumns();

   UInt_t oldwidth = 0, oldheight = 0;
   Int_t i = 0, j = 0;

   oldwidth = GetCHdrWidth();
   oldheight = GetRHdrHeight();

   TGCompositeFrame *container = (TGCompositeFrame *)fCanvas->GetContainer();

   if (newnrows != oldnrows){
      if (newnrows > oldnrows) {
         ExpandRows(newnrows - oldnrows);
      } else {
         ShrinkRows(oldnrows - newnrows);
      }
   }

   if (newncolumns != oldncolumns){
      if (newncolumns > oldncolumns) {
         ExpandColumns(newncolumns - oldncolumns);
      } else {
         ShrinkColumns(oldncolumns - newncolumns);
      }
   }

   // Update the layoutmanager and add the frames.   
   if ((newncolumns != oldncolumns) || (newnrows != oldnrows)) {      
      container->RemoveAll();
      fCellHintsList->Delete();

      fRHdrFrame->RemoveAll();
      fRHdrHintsList->Delete();

      fCHdrFrame->RemoveAll();
      fCHdrHintsList->Delete();

      container->SetLayoutManager(new TGMatrixLayout(container, 
                                                     newnrows, newncolumns));
      // Add frames to layout frames
      TGLayoutHints *lhints = 0;
      for (i = 0; i < (Int_t)newnrows; i++) {
         lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop);
         fRHdrHintsList->Add(lhints);
         fRHdrFrame->AddFrame(GetRowHeader(i), lhints);
         for (j = 0; j < (Int_t)newncolumns; j++) {
            if (i == 0) {
               lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop);
               fCHdrHintsList->Add(lhints);
               fCHdrFrame->AddFrame(GetColumnHeader(j), lhints);
            }
            lhints = new TGLayoutHints(kLHintsLeft | kLHintsTop);
            fCellHintsList->Add(lhints);
            fCanvas->AddFrame(GetCell(i,j), lhints);
         }
      }
   }
   fCanvas->MapSubwindows();
   fCanvas->Layout();
}

//______________________________________________________________________________
void TGTable::UpdateRangeFrame()
{
   // Update the range shown in the range frame.

   TString tl, range;
   
   tl += fCurrentRange->fYtl;
   tl += ",";
   tl += fCurrentRange->fXtl;
   fFirstCellEntry->SetText(tl.Data());

   range += GetNTableRows();
   range += "x";
   range += GetNTableColumns();
   fRangeEntry->SetText(range.Data());

   fGotoButton->SetState(kButtonDisabled);
}

//______________________________________________________________________________
TObjArray *TGTable::GetRow(UInt_t row)
{
   // Get row. NOTE: Do not delete the TObjArray returned or the cells
   // it contains, they are owned by the TGTable.

   return (TObjArray *)fRows->At(row);
}

//______________________________________________________________________________
TObjArray *TGTable::GetColumn(UInt_t column)
{
   // Return a pointer to a TObjArray that contains pointers to all
   // the cells in column. NOTE: The user will have to delete the
   // TObjArray, but do NOT delete the cells it contains, they are
   // owned by the TGTable and will be deleted from the TGTable with
   // undefined consequenses.

   UInt_t nrows = GetNTableRows();

   TObjArray *col = new TObjArray(nrows);
   for(UInt_t ui = 0; ui < nrows; ui++) {
      col->AddAt(GetCell(ui, column), ui);
   }
   return col;
}

// //______________________________________________________________________________
// void TGTable::Select(TGTableCell *celltl, TGTableCell *cellbr)
// {
// }

// //______________________________________________________________________________
// void TGTable::Select(UInt_t xcelltl, UInt_t ycelltl, UInt_t xcell2, UInt_t ycell2)
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectAll()
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectRow(TGTableCell *cell)
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectRow(UInt_t row)
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectRows(UInt_t row, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectColumn(TGTableCell *cell)
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectColumn(UInt_t column)
// {
// }

// //______________________________________________________________________________
// void TGTable::SelectColumns(UInt_t column, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::SetBckgndGC(TGGC *gc)
// {
// }

// //______________________________________________________________________________
// void TGTable::SetSelectGC(TGGC *gc)
// {
// }

// //______________________________________________________________________________
// void TGTable::SetTextJustify(Int_t tmode)
// {
// }

//______________________________________________________________________________
const TGTableCell* TGTable::GetCell(UInt_t i, UInt_t j) const
{
   // Const version of GetCell().

   return const_cast<TGTable *>(this)->GetCell(i, j);
}

//______________________________________________________________________________
TGTableCell* TGTable::GetCell(UInt_t i, UInt_t j)
{
   // Return a pointer to the TGTableCell at position i,j.

   TObjArray *row = (TObjArray *)fRows->At(i);
   if(row) {
      TGTableCell *cell = (TGTableCell *)row->At(j);
      return cell;
   } else {
      return 0;
   }
}

//______________________________________________________________________________
const TGTableCell* TGTable::FindCell(TGString label) const
{
   // Const version of FindCell().

   return const_cast<TGTable *>(this)->FindCell(label);
}

//______________________________________________________________________________
TGTableCell* TGTable::FindCell(TGString label)
{
   // Find the TGTableCell with label.

   TObjArray *row = 0;
   TGTableCell *cell = 0;
   UInt_t i = 0, j = 0;
   //continue here
   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();
   for (i = 0; i < nrows; i++) {
      for (j = 0; j < ncolumns; j++) {
         row = (TObjArray *)fRows->At(j);
         cell = (TGTableCell *)row->At(i);
         if (*(cell->GetLabel()) == label) {
            return cell;
         }
      }
   }
   return 0;
}

//______________________________________________________________________________
void TGTable::Show()
{
   // Show the contents of the TGTable in stdout.

   TGTableCell *cell = 0;
   TGTableHeader *hdr = 0;
   UInt_t i = 0, j = 0;
   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();

   for (j = 0; j < ncolumns + 1; j++) {
      if (j == 0) {
         hdr = fTableHeader;
         if (hdr) std::cout << " " << setw(12) << right 
                            << hdr->GetLabel()->GetString() << " ";
      } else {
         hdr = GetColumnHeader(j - 1);
         if (hdr) std::cout << " " << setw(12) << right 
                            << hdr->GetLabel()->GetString() << " ";
      }
   }
   std::cout << std::endl;

   for (i = 0; i < nrows; i++) {
      for (j = 0; j < ncolumns + 1; j++) {
         if (j == 0) {
            hdr = GetRowHeader(i);
            if (hdr) std::cout << " " << setw(12) << right 
                               << hdr->GetLabel()->GetString() << " ";
         } else {
            cell = GetCell(i, j - 1);
            if (cell) std::cout << " " << setw(12) << right 
                                << cell->GetLabel()->GetString() << " ";
         }
      }
      std::cout << std::endl;
   }
}

// //______________________________________________________________________________
// void TGTable::InsertRowBefore(UInt_t row, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertRowBefore(TGString label, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertRowAfter(UInt_t row, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertRowAfter(TGString label, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertRowAt(UInt_t row, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertRowAt(TGString label, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertColumnBefore(UInt_t column, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertColumnBefore(TGString label, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertColumnAfter(UInt_t column, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertColumnAfter(TGString label, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertColumnAt(UInt_t column, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::InsertColumnAt(TGString label, UInt_t ncolumns)
// {
// }

// //______________________________________________________________________________
// void TGTable::RemoveRows(UInt_t row, UInt_t nrows)
// {
// }

// //______________________________________________________________________________
// void TGTable::RemoveColumns(UInt_t column, UInt_t ncolumns)
// {
// }

//______________________________________________________________________________
void TGTable::UpdateView() 
{
   // Update and layout the visible part of the TGTable.

   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();

   TGString *str = new TGString();
   *str += nrows;
   *str += "x";
   *str += ncolumns;
   *str += " Table";
   fTableHeader->SetLabel(str->GetString());
   delete str;

   UpdateHeaders(kRowHeader);
   UpdateHeaders(kColumnHeader);

   UInt_t i = 0, j = 0;
   UInt_t k = 0, l = 0;

   TGTableCell * cell = 0;
   for (i = 0; i < nrows; i++) {
      for (j = 0; j < ncolumns; j++) {
         cell = GetCell(i,j);
         k = fCurrentRange->fYtl + i;
         l = fCurrentRange->fXtl + j;

         const char *label = fInterface->GetValueAsString(k,l);
         if(cell) cell->SetLabel(label);
      }
   }
   
   MapSubwindows();
   Layout();
   gClient->NeedRedraw(fTableHeader);
   TGViewPort *vp = fCanvas->GetViewPort();
   fTableFrame->DrawRegion(0, 0, vp->GetWidth(), vp->GetHeight());
   fCHdrFrame->DrawRegion(0, 0, fCHdrFrame->GetWidth(), fCHdrFrame->GetHeight());
   fRHdrFrame->DrawRegion(0, 0, fRHdrFrame->GetWidth(), fRHdrFrame->GetHeight());

   UpdateRangeFrame();
}

//______________________________________________________________________________
UInt_t TGTable::GetNTableRows() const
{
   // Return the amount of rows in the table.
   
   return fCurrentRange->fYbr - fCurrentRange->fYtl;
}

//______________________________________________________________________________
UInt_t TGTable::GetNDataRows() const
{
   // Return the amount of rows in the data source.

   return fDataRange->fYbr - fDataRange->fYtl;
}

//______________________________________________________________________________
UInt_t TGTable::GetNTableColumns() const
{
   // Return the amount of columns in the table.

   return fCurrentRange->fXbr - fCurrentRange->fXtl;
}

//______________________________________________________________________________
UInt_t TGTable::GetNDataColumns() const
{
   // Return the amount of columns in the data source.

   return fDataRange->fYbr - fDataRange->fYtl;
}

//______________________________________________________________________________
UInt_t TGTable::GetNTableCells() const
{
   // Return the amount of cells in the table.

   return GetNTableRows() * GetNTableColumns();
}

//______________________________________________________________________________
UInt_t TGTable::GetNDataCells() const
{
   // Return the amount of cell in the data source.

   return GetNDataRows() * GetNDataColumns();
}

//______________________________________________________________________________
const TTableRange *TGTable::GetCurrentRange() const
{
   // Return the current range of the TGTable.

   return fCurrentRange;
}

//______________________________________________________________________________
const TGTableHeader *TGTable::GetRowHeader(const UInt_t row) const
{
   // Const version of GetRowHeader();

   return const_cast<TGTable *>(this)->GetRowHeader(row);
}

//______________________________________________________________________________
TGTableHeader *TGTable::GetRowHeader(const UInt_t row)
{
   // Return a pointer to the header of row.

   return (TGTableHeader *)fRowHeaders->At(row);
}

//______________________________________________________________________________
const TGTableHeader *TGTable::GetColumnHeader(const UInt_t column) const
{
   // Const version of GetColumnHeader();

   return const_cast<TGTable *>(this)->GetColumnHeader(column);
}

//______________________________________________________________________________
TGTableHeader *TGTable::GetColumnHeader(const UInt_t column)
{
   // Return a pointer to the header of column.
   
   return (TGTableHeader *)fColumnHeaders->At(column);
}

//______________________________________________________________________________
TGTableHeader *TGTable::GetTableHeader()
{
   // Return a pointer to the table header.

   return fTableHeader;
}

// //______________________________________________________________________________
// const TGGC*  TGTable::GetSelectGC() const
// {
// }

// //______________________________________________________________________________
// const TGGC*  TGTable::GetCellBckgndGC(TGTableCell *cell) const
// {
// }

// //______________________________________________________________________________
// const TGGC*  TGTable::GetCellBckgndGC(UInt_t row, UInt_t column) const
// {
// }

//______________________________________________________________________________
Pixel_t TGTable::GetRowBackground(UInt_t row) const
{
   // Get the background collor for row.

   if (row % 2 == 0) { // Even rows
      return fEvenRowBackground;
   } else {            // Odd rows
      return fOddRowBackground;
   }
}

//______________________________________________________________________________
Pixel_t TGTable::GetHeaderBackground() const
{
   // Get the background color of headers.

   return fHeaderBackground;
}

//______________________________________________________________________________
void TGTable::SetOddRowBackground(Pixel_t pixel)
{
   // Set the background color for all odd numbered rows.

   if(pixel == fOddRowBackground) return;

   fOddRowBackground = pixel;

   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();
   UInt_t i = 0, j = 0;
   TGTableCell *cell = 0;
   
   for (i = 0; i < nrows; i++) {
      for (j = 0; j < ncolumns; j++) {
         if (i % 2) {
            cell = GetCell(i,j);
            cell->SetBackgroundColor(fOddRowBackground);
         }
      }
   }
   
   UInt_t width = fCanvas->GetViewPort()->GetWidth();
   UInt_t height = fCanvas->GetViewPort()->GetHeight();
   fTableFrame->DrawRegion(0, 0, width, height);
}

//______________________________________________________________________________
void TGTable::SetEvenRowBackground(Pixel_t pixel)
{
   // Set the background color for all even numbered rows.

   if(pixel == fEvenRowBackground) return;

   fEvenRowBackground = pixel;

   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();
   UInt_t i = 0, j = 0;
   TGTableCell *cell = 0;

   for (i = 0; i < nrows; i++) {
      for (j = 0; j < ncolumns; j++) {
         if (!(i % 2)) { 
            cell = GetCell(i,j);
            cell->SetBackgroundColor(fEvenRowBackground);
         }
      }
   }
   UInt_t width = fCanvas->GetViewPort()->GetWidth();
   UInt_t height = fCanvas->GetViewPort()->GetHeight();
   fTableFrame->DrawRegion(0, 0, width, height);
}

//______________________________________________________________________________
void TGTable::SetHeaderBackground(Pixel_t pixel)
{
   // Set the background color for the headers.

   if(pixel == fHeaderBackground) return;

   fHeaderBackground = pixel;

   UInt_t nrows = GetNTableRows();
   UInt_t ncolumns = GetNTableColumns();
   UInt_t i = 0, j = 0;
   TGTableHeader *hdr = 0;

   for (i = 0; i < nrows; i++) {
      hdr = GetRowHeader(i);
      hdr->SetBackgroundColor(fHeaderBackground);
   }
   UInt_t height = fCanvas->GetViewPort()->GetHeight();
   UInt_t width = fTableHeader->GetWidth();
   fRHdrFrame->DrawRegion(0, 0, width, height);

   for (j = 0; j < ncolumns; j++) {
      hdr = GetColumnHeader(j);
      hdr->SetBackgroundColor(fHeaderBackground);
//       gClient->NeedRedraw(hdr);
   }
   width = fCanvas->GetViewPort()->GetWidth();
   height = fTableHeader->GetHeight();
   fCHdrFrame->DrawRegion(0, 0, width, height);
}

//______________________________________________________________________________
void TGTable::SetDefaultColors()
{
   // Set the background color for all rows and headers to their defaults.

   SetEvenRowBackground(TColor::RGB2Pixel(204, 255, 204));
   SetOddRowBackground(TColor::RGB2Pixel(255, 255, 255));
   SetHeaderBackground(TColor::RGB2Pixel(204, 204, 255));
}

//______________________________________________________________________________
void TGTable::MoveTable(Int_t rows, Int_t columns)
{
   // Move and layout the table to the specified range. 

   if (fAllData) return;

   Int_t xtl = fCurrentRange->fXtl + columns;
   Int_t ytl = fCurrentRange->fYtl + rows;
   Int_t xbr = fCurrentRange->fXbr + columns;
   Int_t ybr = fCurrentRange->fYbr + rows;

   GotoTableRange(xtl, ytl, xbr, ybr);
}

//______________________________________________________________________________
void TGTable::GotoTableRange(Int_t xtl,  Int_t ytl, Int_t xbr,  Int_t ybr)
{
   // Move and resize the table to the specified range. 

   if (fAllData) return;

   if(xtl == xbr || ytl == ybr) {
      Error("TGTable::GotoTableRange","x or y range = 0");
      return;
   }

   Int_t nrows    = TMath::Abs(ybr - ytl);
   Int_t ncolumns = TMath::Abs(xbr - xtl);

   if (xtl > xbr) {
      Info("TGTable::GotoTableRange","Swapping x-range boundries");
      Int_t temp = xtl;
      xtl = xbr;
      xbr = temp;
   }
   if (ytl > ybr) {
      Info("TGTable::GotoTableRange","Swapping y-range boundries");
      Int_t temp = ytl;
      ytl = ybr;
      ybr = temp;
   }
   
   if((xtl < 0) || (xbr < 0)) {
      Info("TGTable::GotoTableRange", "Column boundry out of bounds, adjusting");
      xtl = 0;
      xbr = ncolumns;
      if (xbr > (Int_t)fDataRange->fXbr) {
         xbr = fDataRange->fXbr;
         ncolumns = TMath::Abs(xbr - xtl);
      }
   }

   if((ytl < 0) || (ybr < 0)) {
      Info("TGTable::GotoTableRange", "Row boundry out of bounds, adjusting");
      ytl = 0;
      ybr = nrows;
      if (ybr > (Int_t)fDataRange->fYbr) {
         ybr = fDataRange->fYbr;
         nrows =  TMath::Abs(ybr - ytl);
      }
   }

   if((xtl > (Int_t)fDataRange->fXbr) || (xbr > (Int_t)fDataRange->fXbr)) {
      Info("TGTable::GotoTableRange", "Left Column boundry out of bounds, "
           "adjusting");
      xbr = fDataRange->fXbr;
      xtl = xbr - ncolumns;
      if (xtl < 0) {
         xtl = 0;
         ncolumns = TMath::Abs(xbr - xtl);
         Info("TGTable::GotoTableRange", "Right column boundry out of"
                                         " bounds, set to 0");
      }
   }
   if ((ytl > (Int_t)fDataRange->fYbr) || (ybr > (Int_t)fDataRange->fYbr)) {
      Info("TGTable::GotoTableRange", "Bottom row boundry out of bounds, "
                                      "adjusting");
      ybr = fDataRange->fYbr;
      ytl = ybr - nrows;
      if (ytl < 0) {
         ytl = 0;
         nrows = ybr - ytl;
         Info("TGTable::GotoTableRange", "Top row boundry out of bounds, "
                                         "set to 0");
      }
   }

   nrows    = TMath::Abs(ybr - ytl);
   ncolumns = TMath::Abs(xbr - xtl);

   // Resize rows and columns if needed
   ResizeTable(nrows, ncolumns);

   fCurrentRange->fXtl = xtl;
   fCurrentRange->fYtl = ytl;
   fCurrentRange->fXbr = xbr;
   fCurrentRange->fYbr = ybr;

   // Update the table view.
   UpdateView();
}

//______________________________________________________________________________
TGTableCell *TGTable::operator() (UInt_t row, UInt_t column)
{
   // Operator for easy cell acces.

   return GetCell(row, column);
}  

//______________________________________________________________________________
void TGTable::ScrollCHeaders(Int_t xpos)
{
   // Scroll the column headers horizontally.

   if (!fCHdrFrame) return;   

   fCHdrFrame->Move(- xpos, 0);
   fCHdrFrame->Resize();
   fCHdrFrame->DrawRegion(0, 0, fCHdrFrame->GetWidth(), 
                          fCHdrFrame->GetHeight());
}

//______________________________________________________________________________
void TGTable::ScrollRHeaders(Int_t ypos)
{
   // Scroll the row headers vertically

   if (!fRHdrFrame) return;   

   fRHdrFrame->Move(fRHdrFrame->GetX(), -ypos);
   fRHdrFrame->Resize();
   fRHdrFrame->DrawRegion(0, 0, fRHdrFrame->GetWidth(), 
                          fRHdrFrame->GetHeight());
}

//______________________________________________________________________________
void TGTable::NextChunk()
{
   // Move the table to the next chunk of the data set with the same size.

   MoveTable(GetNTableRows(), 0);
   UpdateRangeFrame();
}

//______________________________________________________________________________
void TGTable::PreviousChunk()
{
   // Move the table to the previous chunk of the data set with the same size.

   MoveTable(-1 * GetNTableRows(), 0);
   UpdateRangeFrame();
}

//______________________________________________________________________________
void TGTable::Goto()
{
   // Slot used by the Goto button and whenever return is pressed in
   // on of the text entries in the range frame.

   if (fGotoButton->GetState() == kButtonUp) {
      GotoTableRange(fGotoRange->fXtl, fGotoRange->fYtl, 
                     fGotoRange->fXbr, fGotoRange->fYbr);
      UpdateRangeFrame();
   }
}

//______________________________________________________________________________
void TGTable::UserRangeChange()
{
   // Slot used when the text in one of the range frame text entries changes.

   TString topleft(fFirstCellEntry->GetText());
   if(!topleft.Contains(",")) return;

   Int_t pos = topleft.First(',');
   TString itl = topleft(0,pos);
   TString jtl = topleft(pos+1, topleft.Length());

   if (itl.Contains(' ') || itl.Contains('\t') || 
       jtl.Contains(' ') || jtl.Contains('\t')) return;

   if (!itl.IsAlnum() || !jtl.IsAlnum()) return;

   fGotoRange->fXtl = jtl.Atoi();
   fGotoRange->fYtl = itl.Atoi();

   TString range(fRangeEntry->GetText());
   if(!range.Contains("x")) return;

   pos = 0;
   pos = range.First('x');
   TString ir = range(0,pos);
   TString jr = range(pos+1, range.Length());

   if (ir.Contains(' ') || ir.Contains('\t') || 
       jr.Contains(' ') || jr.Contains('\t')) return;
   if (!ir.IsAlnum() || !jr.IsAlnum()) return;

   fGotoRange->fXbr = jtl.Atoi() + jr.Atoi();
   fGotoRange->fYbr = itl.Atoi() + ir.Atoi();

   if (*fGotoRange == *fCurrentRange) {
      fGotoButton->SetState(kButtonDisabled);
   } else {
      fGotoButton->SetState(kButtonUp);
   }

}

//______________________________________________________________________________
void TGTable::Update() 
{
   // Update the range of the available data and refresh the current view.

   fDataRange->fXbr = fInterface->GetNColumns();
   fDataRange->fYbr = fInterface->GetNRows();
   
   GotoTableRange(fCurrentRange->fXtl, fCurrentRange->fYtl,
                  fCurrentRange->fXbr, fCurrentRange->fYbr);

   UpdateView();
}

//______________________________________________________________________________
TTableRange::TTableRange() : fXtl(0), fYtl(0), fXbr(0), fYbr(0)
{
   // TTableRange constuctor.
}

//______________________________________________________________________________
void TTableRange::Print()
{
   // Print the values of a range.

   std::cout << "Range = (" << fXtl << "," << fYtl << ")->(" 
             << fXbr << "," << fYbr << ")" << std::endl;
}

//______________________________________________________________________________
Bool_t TTableRange::operator==(TTableRange &other)
{
   // Operator to determine if 2 ranges are equal

   if ((fXtl == other.fXtl) && (fYtl == other.fYtl) && 
       (fXbr == other.fXbr) && (fYbr == other.fYbr)) {
      return kTRUE;
   } else {
      return kFALSE;
   }           
}