cannon.cpp

在这个例子中我们开始画一个蓝色可爱的小加农炮

#include "cannon.h"
#include <qpainter.h>
//#include <qcstring.h>
#include <qtextcodec.h>

CannonField::CannonField( QWidget *parent, const char *name )
        : QWidget( parent, name )
{
    ang = 45;
    setPalette( QPalette( QColor( 250, 250, 200) ) );
}


void CannonField::setAngle( int degrees )
{
    if ( degrees < 5 )
        degrees = 5;
    if ( degrees > 70 )
        degrees = 70;
    if ( ang == degrees )
        return;
    ang = degrees;
    repaint();
    emit angleChanged( ang );
}


void CannonField::paintEvent( QPaintEvent * )
{
    //the following 6 lines added by jack on 2007.1.2
    QTextCodec *codec;
    QString cn_s = "角度";
    codec = QTextCodec::codecForName( "gbk" );
    QString sn = codec->toUnicode( cn_s );
    //QString &ss = sn;
    QString s = sn + "Angle = " + QString::number( ang );
    QPainter p( this );
    p.drawText( this->width()/2+10, this->height()/2+10, s );
}


QSizePolicy CannonField::sizePolicy() const
{
    return QSizePolicy( QSizePolicy::Expanding, QSizePolicy::Expanding );
}