看qt书的第一个作品

  最近看了《c++ GUI qt4编程》，做了个简单的程序。。。

是第五章的“创建自定义窗口部件”，是一个图标编辑器。。。

书上只能一个一个的点，我另外加了点功能，就是可以拖动，并且颜色会随机改变。。。

代码如下：

//        iconeditor.h

#ifndef ICONEDITOR_H

#define ICONEDITOR_H

#include <QColor>

#include <QImage>

#include <QWidget>

class IconEditor:public QWidget

{

    Q_OBJECT

    Q_PROPERTY(QColor penColor READ penColor WRITE setPenColor)

    Q_PROPERTY(QImage iconImage READ iconImage WRITE setIconImage)

    Q_PROPERTY(int zoomFactor READ zoomFactor WRITE setZoomFactor)

public:

    IconEditor(QWidget *parent=0);

    void setPenColor(QColor const& newColor);

    QColor penColor() const

    {

        return curColor;

    }

    void setZoomFactor(int newZoom);

    int zoomFactor() const

    {

        return zoom;

    }

    void setIconImage(QImage const& newImage);

    QImage iconImage() const

    {

        return image;

    }

    QSize sizeHint() const;

protected:

    void mousePressEvent(QMouseEvent *event);

    void mouseMoveEvent(QMouseEvent *event);

    void mouseReleaseEvent(QMouseEvent *event);

    void paintEvent(QPaintEvent *event);

private:

    void setImagePixel(QPoint const& pos,bool opaque);

    QRect pixelRect(int i,int j) const;

    QColor curColor;

    QImage image;

    int zoom;

    bool s;

};

#endif // ICONEDITOR_H

//         iconeditor.cpp

#include <QtGui>

#include "iconeditor.h"

#include "QTime"

IconEditor::IconEditor(QWidget *parent):QWidget(parent)

{

    setWindowIcon(QIcon(":/title.png"));

    setAttribute(Qt::WA_StaticContents);

    setSizePolicy(QSizePolicy::Minimum,QSizePolicy::Minimum);

    curColor=Qt::green;

    zoom=8;

    image=QImage(100,100,QImage::Format_ARGB32);

    image.fill(qRgba(0,0,0,0));

}

QSize IconEditor::sizeHint() const

{

    QSize size=zoom*image.size();

    if(zoom>=3)

        size+=QSize(1,1);

    return size;

}

void IconEditor::setPenColor(QColor const& newColor)

{

    curColor=newColor;

}

void IconEditor::setIconImage(const QImage &newImage)

{

    if(newImage!=image)

    {

        image=newImage.convertToFormat(QImage::Format_ARGB32);

        update();

        updateGeometry();

    }

}

void IconEditor::setZoomFactor(int newZoom)

{

    if(newZoom<1)

        newZoom=1;

    if(newZoom!=zoom)

    {

        zoom=newZoom;

        update();

        updateGeometry();

    }

}

void IconEditor::paintEvent(QPaintEvent *event)

{

    QPainter painter(this);

    if(zoom>=3)

    {

        painter.setPen(palette().foreground().color());

        for(int i=0;i<=image.width();++i)

            painter.drawLine(zoom*i,0,

                             zoom*i,zoom*image.height());

        for(int j=0;j<=image.height();++j)

            painter.drawLine(0,zoom*j,

                             zoom*image.width(),zoom*j);

    }

    for(int i=0;i<image.width();++i)

        for(int j=0;j<image.height();++j)

        {

            QRect rect=pixelRect(i,j);

            if(!event->region().intersect(rect).isEmpty())

            {

                QColor color=QColor::fromRgba(image.pixel(i,j));

                if(color.alpha()<255)

                    painter.fillRect(rect,Qt::white);

                painter.fillRect(rect,color);

            }

        }

}

QRect IconEditor::pixelRect(int i, int j) const

{

    if(zoom>=3)

    {

        return QRect(zoom*i+1,zoom*j+1,zoom-1,zoom-1);

    }

    else

    {

        return QRect(zoom*i,zoom*j,zoom,zoom);

    }

}

void IconEditor::mousePressEvent(QMouseEvent *event)

{

    s=true;

    QTime t;

    t= QTime::currentTime();

    qsrand(t.msec()+t.second()*1000);

    //int n = qrand();

    if(event->button()==Qt::LeftButton)

    {

        setImagePixel(event->pos(),true);

        curColor=QColor(qrand()%255,qrand()%255,qrand()%255,qrand()%255);

    }

    else if(event->button()==Qt::RightButton)

    {

        setImagePixel(event->pos(),false);

    }

}

void IconEditor::mouseReleaseEvent(QMouseEvent *event)

{

    s=false;

}

void IconEditor::mouseMoveEvent(QMouseEvent *event)

{

    if(s==true)

        setImagePixel(event->pos(),true);

    if(event->button()&Qt::LeftButton)

    {

        setImagePixel(event->pos(),true);

    }

    else if(event->button()&Qt::RightButton)

    {

        setImagePixel(event->pos(),false);

    }

}

void IconEditor::setImagePixel(const QPoint &pos, bool opaque)

{

    int i=pos.x()/zoom;

    int j=pos.y()/zoom;

    if(image.rect().contains(i,j))

    {

        if(opaque)

        {

            image.setPixel(i,j,penColor().rgba());

        }

        else

        {

            image.setPixel(i,j,qRgba(0,0,0,0));

        }

        update(pixelRect(i,j));

    }

}