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Example1

This example shows how to use an object of the class QdbtTabular. Some things the user of the application can do:

Resize the columns (press the left mouse button on one of the dividers in header and drag the slider bar).
Resize the column so all cells hit (press the middle mouse button on one of the dividers)
If a column is too narrow to contain the text of a cell the text will be truncated using dots (..)
If a column is too narrow to contain the text of a cell, a tooltip will appear when you rest your mouse point on that cell.
Pressing the middle mousebutton on a cell in the first column will enable you to edit the text of the cell. Notice that cells in the second column cannot be edited (This behavior can ofcourse be changed by the application programmer).
By clicking the left mouse button on a row and dragging it multiple rows can be selected. Notice that the table starts scrolling if you drag to a part of the table that is not yet visible. You can even control the scroll speed !

It also demostrates that columns and rows can be inserted and removed on the fly.

The header file:

#ifndef _EXAMPLE1_H
#define _EXAMPLE1_H

#include <qwidget.h>
#include <qpixmap.h>
#include <qlined.h>
#include <qcombo.h>

class QdbtTabular;

class Example : public QWidget
{
  Q_OBJECT

  public:
    Example(QWidget *parent=0, const char *name=0, WFlags f=0);
   ~Example();
 
  private slots:
    void toggleHeader(bool);
    void addRow();
    void delRows();
    void addCol();
    void delCol();
    void clear();

  private:
    QLineEdit *nameEdit,*sizeEdit;
    QComboBox *type;
    QdbtTabular *tabular;
    QPixmap folder,file;
};

#endif

The source file:

#include <stdio.h>
#include <stdlib.h>
#include <qapp.h>
#include <qlayout.h>
#include <qpushbt.h>
#include <qlabel.h>

#include "example1.h"
#include <qdbt/qdbttabular.h>
#include <qdbt/qdbttabcell.h>
#include <qdbt/qdbtsection.h>

// constructor
Example::Example(QWidget *parent,const char *name, WFlags f) 
      : QWidget(parent,name,f)
{
  // Set the caption of the window
  setCaption("Example");

  // The Layout managers
  QGridLayout *layout  = new QGridLayout(this,3,1,5);
  QGridLayout *input   = new QGridLayout(1,5,5);
  QBoxLayout  *buttons = new QBoxLayout(QBoxLayout::LeftToRight);
  
  // Create a new QdbtTabular object
  tabular=new QdbtTabular(this);

  // Set the font of the cells in the table
  tabular->setCellFont(QFont("helvetica",12,QFont::Bold));

  // Set the minimal widget size
  tabular->setMinimumSize(100,100);

  // Load the folder pixmap (No error checking!)
  folder.load("folder.xpm");

  // Load the file pixmap (No error checking!)
  file.load("file.xpm");

  // set the initial table size (this is faster than
  // inserting the columns and rows one by one
  tabular->setDimensions(10,2);

  // Set the font of the header
  tabular->setHeaderFont(QFont("helvetica",16,QFont::Bold));

  // change the heading of column 0 (default is empty)
  QdbtSection *section0=tabular->section(0);
  section0->setText("Name");

  // change the heading and alignment of column 1
  QdbtSection *section1=tabular->section(1);
  section1->setText("Size");
  section1->setAlignment(AlignRight);

  int i;
  for (i=0;i<10;i++)
  {
    QString name,size;
    name.sprintf("%s%d\n",i<5 ? "folder" : "file",i<5 ? i : i-5);
    size.sprintf("%d",i*1024+1024);
    QdbtTableCell cell;

    // define a cell `cell'
    cell.setText(name);
    cell.setPixmap(i<5 ? &folder : &file);
    cell.setEditable(FALSE);
    cell.setAlignment(AlignLeft);
    cell.setPixmapAlignment(AlignLeft);
    cell.setColor(i<5 ? blue : black);
    // let cell (i,0) be a (deep) copy of `cell' 
    tabular->changeCell(&cell,i,0);

    // modify the cell `cell'
    if (i<5) cell.setText(0); else cell.setText(size);
    cell.setPixmap(0);
    cell.setEditable(TRUE);
    cell.setAlignment(AlignRight);
    // let cell (i,1) be a (deep) copy of `cell'
    tabular->changeCell(&cell,i,1);
  }

  // Set the width of the columns, so all cells fit
  tabular->setColumnWidth(0,tabular->columnWidthHint(0));
  tabular->setColumnWidth(1,tabular->columnWidthHint(1));
  
  // Get the height of the default font (can be changed with the -fn option)
  int fh=fontMetrics().height();

  // Create the input widgets
  QLabel *nameLab  = new QLabel("Name",this);
  QLabel *sizeLab  = new QLabel("Size",this);
  nameEdit = new QLineEdit(this);
  sizeEdit = new QLineEdit(this);
  type     = new QComboBox(this);

  // Set their minimum sizes
  nameLab->setMinimumSize(nameLab->sizeHint());
  sizeLab->setMinimumSize(sizeLab->sizeHint());
  type->insertItem("folder");
  type->insertItem("file");
  type->setMinimumSize(type->sizeHint());
  nameEdit->setMinimumSize(50,fh+6); // height depends on the font that is used
  sizeEdit->setMinimumSize(50,fh+6);

  // Create the control button
  QPushButton *add    = new QPushButton("Add",this);
  QPushButton *addCol = new QPushButton("AddCol",this);
  QPushButton *del    = new QPushButton("Del",this);
  QPushButton *delCol = new QPushButton("DelCol",this);
  QPushButton *clear  = new QPushButton("Clear",this);
  QPushButton *header = new QPushButton("Header",this);
  QPushButton *close  = new QPushButton("Close",this);

  // Set their minimum sizes
  add   ->setMinimumSize(add->sizeHint());
  del   ->setMinimumSize(del->sizeHint());
  addCol->setMinimumSize(addCol->sizeHint());
  delCol->setMinimumSize(delCol->sizeHint());
  close ->setMinimumSize(close->sizeHint());
  clear ->setMinimumSize(clear->sizeHint());
  header->setMinimumSize(header->sizeHint());
  header->setToggleButton(TRUE); // make the header button a toggle button
  header->setOn(TRUE);           // and turn it on

  // Add Widgets and layouts to the layout-manager
  layout->addWidget(tabular,0,0);
  layout->addLayout(input  ,1,0);
  layout->addLayout(buttons,2,0);
  layout->setColStretch(0,1); // make the table strechable
  layout->setRowStretch(0,1);

  // Add Widgets to the button layout
  buttons->addStretch(1);
  buttons->addWidget(add);
  buttons->addWidget(del);
  buttons->addWidget(addCol);
  buttons->addWidget(delCol);
  buttons->addWidget(clear);
  buttons->addWidget(header);
  buttons->addWidget(close);

  // Add Widgets to the input layout
  input->addWidget(type,0,4);
  input->addWidget(nameLab,0,0);
  input->addWidget(nameEdit,0,1);
  input->setColStretch(1,1); // make the edit field horizontal stretchable 
  input->addWidget(sizeLab,0,2);
  input->addWidget(sizeEdit,0,3);
  input->setColStretch(3,1);
 
  // don't forget to activate the top layout manager
  layout->activate();

  // Let the close button quit the application
  connect(close,  SIGNAL(clicked()),qApp,SLOT(quit()));
  
  // Let the toggle button hide/show the header
  connect(header, SIGNAL(toggled(bool)),SLOT(toggleHeader(bool)));
 
  // Connect the add button to the addRow() function
  connect(add,    SIGNAL(clicked()),SLOT(addRow()));

  // Connect the del button to the delRow() function
  connect(del,    SIGNAL(clicked()),SLOT(delRows()));
  
  // Connect the add column button to the addCol() function
  connect(addCol, SIGNAL(clicked()),SLOT(addCol()));

  // Connect the del column button to the delCol() function
  connect(delCol, SIGNAL(clicked()),SLOT(delCol()));
  
  // Connect the clean button to the clear() function
  connect(clear,  SIGNAL(clicked()),SLOT(clear()));
  
  // Resize the widget to its minimal size
  resize(layout->mainWidget()->sizeHint());
}

// destructor
Example::~Example()
{
}

// hide/show table's header
void Example::toggleHeader(bool state)
{
  if (state) tabular->showHeader(); else tabular->hideHeader();
}

// add a row to the table
void Example::addRow()
{
  if (nameEdit->text() && strlen(nameEdit->text())>0) // text field not empty
  {
    int nRows=tabular->numRows();
    int nCols=tabular->numCols();
    tabular->insertRow(nRows);     // add a new row at the end of the table

    if (type->currentItem()==0)    // type==folder
    {
      if (nCols>0) tabular->changeCell(nameEdit->text(),&folder,nRows,0,blue,AlignLeft,TRUE);
      if (nCols>1) tabular->changeCell("",nRows,1,blue);
    } 
    else // type->currentItem()==1 // type==file
    {
      if (nCols>0) tabular->changeCell(nameEdit->text(),&file,nRows,0,black,AlignLeft,TRUE);
      if (nCols>1) tabular->changeCell(sizeEdit->text(),nRows,1,black,AlignRight);
    }
  }
}

// delete all selected rows from the table
void Example::delRows()
{
  tabular->setAutoUpdate(FALSE);  // temporarily disable updates, otherwise
                                  // update is called for each row
  int i=0;
  while (i<tabular->numRows()) // not all rows inspected
  {
    if (!tabular->rowSelected(i)) // if row not selected
      i++;                        // proceed with the next row
    else                          // otherwise
      tabular->removeRow(i);      // remove this row (will decrease numRows())
  }
  tabular->setAutoUpdate(TRUE);   // enable the update again
  tabular->repaint();             // repaint the table
}

// add a new column to the table
void Example::addCol()
{
  tabular->setAutoUpdate(FALSE);  // temporarily disable updates, otherwise
  int colIndex=tabular->numCols();
  tabular->insertCol(colIndex);
  tabular->section(colIndex)->setText("New Column");
  tabular->setColumnWidth(colIndex,tabular->columnWidthHint(colIndex));
  // modify the cells of the new column
  int i,nRows=tabular->numRows();
  for (i=0;i<nRows;i++)
  {
    QdbtTableCell cell;
    QString text;
    text.sprintf("cell (%d,%d)",i,colIndex);
    cell.setText(text);
    cell.setEditable(TRUE);
    tabular->changeCell(&cell,i,colIndex);
  }
  tabular->setAutoUpdate(TRUE);   // enable the update again
  tabular->repaint();             // repaint the table
}

// delete the last column from the table (if any)
void Example::delCol()
{
  int nCols=tabular->numCols();
  if (nCols>0)
  {
    tabular->removeCol(nCols-1);
  }
}

// clear the whole table (removes all rows and columns)
void Example::clear()
{
  tabular->clear();
}

int main(int argc,char **argv)
{
  QApplication app(argc, argv);
  Example example;
  app.setMainWidget(&example);
  example.show();
  return app.exec();  
}

Generated at 21:52, 1998/03/04 for QdbtTabular by