6.9 实例：基本绘画操作.txt

qt的源代码

 class Window : public QWidget
 {
     Q_OBJECT
 public:
     Window();
 private slots:
     void shapeChanged();
     void penChanged();
     void brushChanged();
 private:
     RenderArea *renderArea;
     QLabel *shapeLabel;
     QLabel *penWidthLabel;
     QLabel *penStyleLabel;
     QLabel *penCapLabel;
     QLabel *penJoinLabel;
     QLabel *brushStyleLabel;
     QLabel *otherOptionsLabel;
     QComboBox *shapeComboBox;
     QSpinBox *penWidthSpinBox;
     QComboBox *penStyleComboBox;
     QComboBox *penCapComboBox;
     QComboBox *penJoinComboBox;
     QComboBox *brushStyleComboBox;
     QCheckBox *antialiasingCheckBox;
     QCheckBox *transformationsCheckBox;
 }; 
Window::Window()
 {
     renderArea = new RenderArea;
     shapeComboBox = new QComboBox;
     shapeComboBox->addItem(tr("Polygon"), RenderArea::Polygon);
     shapeComboBox->addItem(tr("Rectangle"), RenderArea::Rect);
     shapeComboBox->addItem(tr("Rounded Rectangle"), RenderArea::RoundedRect);
     shapeComboBox->addItem(tr("Ellipse"), RenderArea::Ellipse);
     shapeComboBox->addItem(tr("Pie"), RenderArea::Pie);
     shapeComboBox->addItem(tr("Chord"), RenderArea::Chord);
     shapeComboBox->addItem(tr("Path"), RenderArea::Path);
     shapeComboBox->addItem(tr("Line"), RenderArea::Line);
     shapeComboBox->addItem(tr("Polyline"), RenderArea::Polyline);
     shapeComboBox->addItem(tr("Arc"), RenderArea::Arc);
     shapeComboBox->addItem(tr("Points"), RenderArea::Points);
     shapeComboBox->addItem(tr("Text"), RenderArea::Text);
     shapeComboBox->addItem(tr("Pixmap"), RenderArea::Pixmap);
     shapeLabel = new QLabel(tr("&Shape:"));
     shapeLabel->setBuddy(shapeComboBox);
penWidthSpinBox = new QSpinBox;
     penWidthSpinBox->setRange(0, 20);
     penWidthSpinBox->setSpecialValueText(tr("0 (cosmetic pen)"));
     penWidthLabel = new QLabel(tr("Pen &Width:"));
     penWidthLabel->setBuddy(penWidthSpinBox);
penStyleComboBox = new QComboBox;
     penStyleComboBox->addItem(tr("Solid"), Qt::SolidLine);
     penStyleComboBox->addItem(tr("Dash"), Qt::DashLine);
     penStyleComboBox->addItem(tr("Dot"), Qt::DotLine);
     penStyleComboBox->addItem(tr("Dash Dot"), Qt::DashDotLine);
     penStyleComboBox->addItem(tr("Dash Dot Dot"), Qt::DashDotDotLine);
     penStyleComboBox->addItem(tr("None"), Qt::NoPen);
     penStyleLabel = new QLabel(tr("&Pen Style:"));
     penStyleLabel->setBuddy(penStyleComboBox);
     penCapComboBox = new QComboBox;
     penCapComboBox->addItem(tr("Flat"), Qt::FlatCap);
     penCapComboBox->addItem(tr("Square"), Qt::SquareCap);
     penCapComboBox->addItem(tr("Round"), Qt::RoundCap);
     penCapLabel = new QLabel(tr("Pen &Cap:"));
     penCapLabel->setBuddy(penCapComboBox);
     penJoinComboBox = new QComboBox;
     penJoinComboBox->addItem(tr("Miter"), Qt::MiterJoin);
     penJoinComboBox->addItem(tr("Bevel"), Qt::BevelJoin);
     penJoinComboBox->addItem(tr("Round"), Qt::RoundJoin);
     penJoinLabel = new QLabel(tr("Pen &Join:"));
     penJoinLabel->setBuddy(penJoinComboBox);
   brushStyleComboBox = new QComboBox;
     brushStyleComboBox->addItem(tr("Linear Gradient"),
             Qt::LinearGradientPattern);
     brushStyleComboBox->addItem(tr("Radial Gradient"),
             Qt::RadialGradientPattern);
     brushStyleComboBox->addItem(tr("Conical Gradient"),
             Qt::ConicalGradientPattern);
     brushStyleComboBox->addItem(tr("Texture"), Qt::TexturePattern);
     brushStyleComboBox->addItem(tr("Solid"), Qt::SolidPattern);
     brushStyleComboBox->addItem(tr("Horizontal"), Qt::HorPattern);
     brushStyleComboBox->addItem(tr("Vertical"), Qt::VerPattern);
     brushStyleComboBox->addItem(tr("Cross"), Qt::CrossPattern);
     brushStyleComboBox->addItem(tr("Backward Diagonal"), Qt::BDiagPattern);
     brushStyleComboBox->addItem(tr("Forward Diagonal"), Qt::FDiagPattern);
     brushStyleComboBox->addItem(tr("Diagonal Cross"), Qt::DiagCrossPattern);
  brushStyleComboBox->addItem(tr("Dense 1"), Qt::Dense1Pattern);
     brushStyleComboBox->addItem(tr("Dense 2"), Qt::Dense2Pattern);
     brushStyleComboBox->addItem(tr("Dense 3"), Qt::Dense3Pattern);
     brushStyleComboBox->addItem(tr("Dense 4"), Qt::Dense4Pattern);
     brushStyleComboBox->addItem(tr("Dense 5"), Qt::Dense5Pattern);
     brushStyleComboBox->addItem(tr("Dense 6"), Qt::Dense6Pattern);
     brushStyleComboBox->addItem(tr("Dense 7"), Qt::Dense7Pattern);
     brushStyleComboBox->addItem(tr("None"), Qt::NoBrush);
     brushStyleLabel = new QLabel(tr("&Brush Style:"));
     brushStyleLabel->setBuddy(brushStyleComboBox);
   otherOptionsLabel = new QLabel(tr("Other Options:"));
        antialiasingCheckBox = new QCheckBox(tr("&Antialiasing"));
 connect(shapeComboBox, SIGNAL(activated(int)),
             this, SLOT(shapeChanged()));
     connect(penWidthSpinBox, SIGNAL(valueChanged(int)),
             this, SLOT(penChanged()));
     connect(penStyleComboBox, SIGNAL(activated(int)),
             this, SLOT(penChanged()));
     connect(penCapComboBox, SIGNAL(activated(int)),
             this, SLOT(penChanged()));
     connect(penJoinComboBox, SIGNAL(activated(int)),
             this, SLOT(penChanged()));
     connect(brushStyleComboBox, SIGNAL(activated(int)),
             this, SLOT(brushChanged()));
     connect(antialiasingCheckBox, SIGNAL(toggled(bool)),
             renderArea, SLOT(setAntialiased(bool)));
     connect(transformationsCheckBox, SIGNAL(toggled(bool)),
             renderArea, SLOT(setTransformed(bool)));
 QGridLayout *mainLayout = new QGridLayout;
     mainLayout->setColumnStretch(0, 1);
     mainLayout->setColumnStretch(3, 1);
     mainLayout->addWidget(renderArea, 0, 0, 1, 4);
     mainLayout->setRowMinimumHeight(1, 6);
     mainLayout->addWidget(shapeLabel, 2, 1, Qt::AlignRight);
     mainLayout->addWidget(shapeComboBox, 2, 2);
     mainLayout->addWidget(penWidthLabel, 3, 1, Qt::AlignRight);
     mainLayout->addWidget(penWidthSpinBox, 3, 2);
     mainLayout->addWidget(penStyleLabel, 4, 1, Qt::AlignRight);
     mainLayout->addWidget(penStyleComboBox, 4, 2);
     mainLayout->addWidget(penCapLabel, 5, 1, Qt::AlignRight);
     mainLayout->addWidget(penCapComboBox, 5, 2);
     mainLayout->addWidget(penJoinLabel, 6, 1, Qt::AlignRight);
     mainLayout->addWidget(penJoinComboBox, 6, 2);
     mainLayout->addWidget(brushStyleLabel, 7, 1, Qt::AlignRight);
     mainLayout->addWidget(brushStyleComboBox, 7, 2);
     mainLayout->setRowMinimumHeight(8, 6);
     mainLayout->addWidget(otherOptionsLabel, 9, 1, Qt::AlignRight);
     mainLayout->addWidget(antialiasingCheckBox, 9, 2);
     mainLayout->addWidget(transformationsCheckBox, 10, 2);
     setLayout(mainLayout);
     shapeChanged();
     penChanged();
     brushChanged();
     antialiasingCheckBox->setChecked(true);
     setWindowTitle(tr("Basic Drawing"));
 } 
 void Window::shapeChanged()
 {
     RenderArea::Shape shape = RenderArea::Shape(shapeComboBox->itemData(
             shapeComboBox->currentIndex(), IdRole).toInt());
     renderArea->setShape(shape);
 }
 void Window::penChanged()
 {
     int width = penWidthSpinBox->value();
     Qt::PenStyle style = Qt::PenStyle(penStyleComboBox->itemData(
             penStyleComboBox->currentIndex(), IdRole).toInt());
     Qt::PenCapStyle cap = Qt::PenCapStyle(penCapComboBox->itemData(
             penCapComboBox->currentIndex(), IdRole).toInt());
     Qt::PenJoinStyle join = Qt::PenJoinStyle(penJoinComboBox->itemData(
             penJoinComboBox->currentIndex(), IdRole).toInt());
     renderArea->setPen(QPen(Qt::blue, width, style, cap, join));
 } 
 void Window::brushChanged()
 {
     Qt::BrushStyle style = Qt::BrushStyle(brushStyleComboBox->itemData(  if (style == Qt::LinearGradientPattern) {
         QLinearGradient linearGradient(0, 0, 100, 100);
         linearGradient.setColorAt(0.0, Qt::white);
         linearGradient.setColorAt(0.2, Qt::green);
         linearGradient.setColorAt(1.0, Qt::black);
         renderArea->setBrush(linearGradient);
 if (style == Qt::LinearGradientPattern) {
         QLinearGradient linearGradient(0, 0, 100, 100);
         linearGradient.setColorAt(0.0, Qt::white);
         linearGradient.setColorAt(0.2, Qt::green);
         linearGradient.setColorAt(1.0, Qt::black);
         renderArea->setBrush(linearGradient);