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/****************************************************************************
**
** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
**
** This file is part of an example program for Qt. This example
** program may be used, distributed and modified without limitation.
**
*****************************************************************************/
#include <qtimer.h>
#include <qpainter.h>
#include <qapplication.h>
#include <stdlib.h> // defines rand() function
#include "forever.h"
//
// Forever - a widget that draws rectangles forever.
//
//
// Constructs a Forever widget.
//
Forever::Forever( QWidget *parent, const char *name )
: QWidget( parent, name )
{
for (int a=0; a<numColors; a++) {
colors[a] = QColor( rand()&255,
rand()&255,
rand()&255 );
}
rectangles = 0;
startTimer( 0 ); // run continuous timer
QTimer * counter = new QTimer( this );
connect( counter, SIGNAL(timeout()),
this, SLOT(updateCaption()) );
counter->start( 1000 );
}
void Forever::updateCaption()
{
QString s;
s.sprintf( "Qt Example - Forever - %d rectangles/second", rectangles );
rectangles = 0;
setCaption( s );
}
//
// Handles paint events for the Forever widget.
//
void Forever::paintEvent( QPaintEvent * )
{
QPainter paint( this ); // painter object
int w = width();
int h = height();
if(w <= 0 || h <= 0)
return;
paint.setPen( NoPen ); // do not draw outline
paint.setBrush( colors[rand() % numColors]);// set random brush color
QPoint p1( rand()%w, rand()%h ); // p1 = top left
QPoint p2( rand()%w, rand()%h ); // p2 = bottom right
QRect r( p1, p2 );
paint.drawRect( r ); // draw filled rectangle
}
//
// Handles timer events for the Forever widget.
//
void Forever::timerEvent( QTimerEvent * )
{
for ( int i=0; i<100; i++ ) {
repaint( FALSE ); // repaint, don't erase
rectangles++;
}
}
//
// Create and display Forever widget.
//
int main( int argc, char **argv )
{
QApplication a( argc, argv ); // create application object
Forever always; // create widget
always.resize( 400, 250 ); // start up with size 400x250
a.setMainWidget( &always ); // set as main widget
always.setCaption("Qt Example - Forever");
always.show(); // show widget
return a.exec(); // run event loop
}
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