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//! [0]
void SimpleExampleWidget::paintEvent(QPaintEvent *)
{
QPainter painter(this);
painter.setPen(Qt::blue);
painter.setFont(QFont("Arial", 30));
painter.drawText(rect(), Qt::AlignCenter, "Qt");
}
//! [0]
//! [1]
void MyWidget::paintEvent(QPaintEvent *)
{
QPainter p;
p.begin(this);
p.drawLine(...); // drawing code
p.end();
}
//! [1]
//! [2]
void MyWidget::paintEvent(QPaintEvent *)
{
QPainter p(this);
p.drawLine(...); // drawing code
}
//! [2]
//! [3]
painter->begin(0); // impossible - paint device cannot be 0
QPixmap image(0, 0);
painter->begin(&image); // impossible - image.isNull() == true;
painter->begin(myWidget);
painter2->begin(myWidget); // impossible - only one painter at a time
//! [3]
//! [4]
void QPainter::rotate(qreal angle)
{
QMatrix matrix;
matrix.rotate(angle);
setWorldMatrix(matrix, true);
}
//! [4]
//! [5]
QPainterPath path;
path.moveTo(20, 80);
path.lineTo(20, 30);
path.cubicTo(80, 0, 50, 50, 80, 80);
QPainter painter(this);
painter.drawPath(path);
//! [5]
//! [6]
QLineF line(10.0, 80.0, 90.0, 20.0);
QPainter(this);
painter.drawLine(line);
//! [6]
//! [7]
QRectF rectangle(10.0, 20.0, 80.0, 60.0);
QPainter painter(this);
painter.drawRect(rectangle);
//! [7]
//! [8]
QRectF rectangle(10.0, 20.0, 80.0, 60.0);
QPainter painter(this);
painter.drawRoundedRect(rectangle, 20.0, 15.0);
//! [8]
//! [9]
QRectF rectangle(10.0, 20.0, 80.0, 60.0);
QPainter painter(this);
painter.drawEllipse(rectangle);
//! [9]
//! [10]
QRectF rectangle(10.0, 20.0, 80.0, 60.0);
int startAngle = 30 * 16;
int spanAngle = 120 * 16;
QPainter painter(this);
painter.drawArc(rectangle, startAngle, spanAngle);
//! [10]
//! [11]
QRectF rectangle(10.0, 20.0, 80.0, 60.0);
int startAngle = 30 * 16;
int spanAngle = 120 * 16;
QPainter painter(this);
painter.drawPie(rectangle, startAngle, spanAngle);
//! [11]
//! [12]
QRectF rectangle(10.0, 20.0, 80.0, 60.0);
int startAngle = 30 * 16;
int spanAngle = 120 * 16;
QPainter painter(this);
painter.drawChord(rect, startAngle, spanAngle);
//! [12]
//! [13]
static const QPointF points[3] = {
QPointF(10.0, 80.0),
QPointF(20.0, 10.0),
QPointF(80.0, 30.0),
};
QPainter painter(this);
painter.drawPolyline(points, 3);
//! [13]
//! [14]
static const QPointF points[4] = {
QPointF(10.0, 80.0),
QPointF(20.0, 10.0),
QPointF(80.0, 30.0),
QPointF(90.0, 70.0)
};
QPainter painter(this);
painter.drawPolygon(points, 4);
//! [14]
//! [15]
static const QPointF points[4] = {
QPointF(10.0, 80.0),
QPointF(20.0, 10.0),
QPointF(80.0, 30.0),
QPointF(90.0, 70.0)
};
QPainter painter(this);
painter.drawConvexPolygon(points, 4);
//! [15]
//! [16]
QRectF target(10.0, 20.0, 80.0, 60.0);
QRectF source(0.0, 0.0, 70.0, 40.0);
QPixmap pixmap(":myPixmap.png");
QPainter(this);
painter.drawPixmap(target, image, source);
//! [16]
//! [17]
QPainter painter(this);
painter.drawText(rect, Qt::AlignCenter, tr("Qt by\nTrolltech"));
//! [17]
//! [18]
QPicture picture;
QPointF point(10.0, 20.0)
picture.load("drawing.pic");
QPainter painter(this);
painter.drawPicture(0, 0, picture);
//! [18]
//! [19]
fillRect(rectangle, background()).
//! [19]
//! [20]
QRectF target(10.0, 20.0, 80.0, 60.0);
QRectF source(0.0, 0.0, 70.0, 40.0);
QImage image(":/images/myImage.png");
QPainter painter(this);
painter.drawImage(target, image, source);
//! [20]
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