So I have looked at other similar questions on stackoverflow but none seem to help. The problem is that the animation doesn't occur, but once I click somewhere in the QGraphicsView, it updates to the end position.
I'm animating QGraphicsRectItem with QPropertyAnimation, so I made a new class and extended QObject and QGraphicsRectItem:
class MyGraphicsRectItem : public QObject, public QGraphicsRectItem {
Q_OBJECT
Q_PROPERTY(QPointF position READ position WRITE setPosition)
Q_PROPERTY(QRectF geometry READ geometry WRITE setGeometry)
public:
...
QPointF position();
void setPosition(QPointF animBox);
QRectF geometry();
void setGeometry(QRectF geo);
...
}
One common problem with regarding this problem is that QPropertyAnimation goes out of scope when the function finishes, but I think I circumvented this problem using QAbstractAnimation::DeleteWhenStopped. In my MainWindow.cpp, I have:
group = new QParallelAnimationGroup;
for (int i = 0; i < 10 ; i += 1) {
MyGraphicsRectItem *temp = dynamic_cast<MyGraphicsRectItem*>(histZToItem[i]);
QPropertyAnimation *anim = new QPropertyAnimation(temp, "position");
anim->setDuration(500);
anim->setStartValue(temp->pos());
QPropertyAnimation *geo = new QPropertyAnimation(temp, "geometry");
geo->setDuration(500);
geo->setStartValue(temp->rect());
geo->setEndValue(QRectF(0, 0, colWidth, -80));
if (i > anchorID) {
anim->setEndValue(QPointF(40 + spaceWidth * (i) + colWidth * (i - 1), graphScene->height() - 40));
} else {
anim->setEndValue(QPointF(40 + spaceWidth * (i + 1) + colWidth * (i), graphScene->height() - 40));
}
group->addAnimation(geo);
group->addAnimation(anim);
}
group->start(QAbstractAnimation::DeleteWhenStopped);
Any ideas?
Edit
Here are my implementations for position, setPosition, geometry and setGeometry:
QPointF MyGraphicsRectItem::position()
{
return QGraphicsRectItem::pos();
}
void MyGraphicsRectItem::setPosition(QPointF animPos)
{
QGraphicsRectItem::setPos(animPos);
}
QRectF MyGraphicsRectItem::geometry()
{
return rect();
}
void MyGraphicsRectItem::setGeometry(QRectF geo)
{
setRect(geo);
}
EDIT 2
Here's the constructor:
MyGraphicsRectItem::MyGraphicsRectItem(qreal x, qreal y, qreal width, qreal height, QGraphicsItem *parent) :QGraphicsRectItem(x, y, width, height, parent) {
setAcceptHoverEvents(true);
}
Related
I'm using this solution to animate ellipses along a QPainterPath.
But I need to slowly increase or decrease the speed of the animation.
I create a timer and set a new duration for the animation but the result is a choppy animation because the ellipses start from the beginning.
Is there a better way to accomplish this?
class AnimatedEllipses: public QGraphicsObject
{
Q_OBJECT
Q_PROPERTY(int progress READ progress WRITE setProgress)
private:
QGraphicsPathItem path;
QList<QGraphicsEllipseItem*> ellipses;
int propProgress;
QPropertyAnimation* animation;
public:
int progress() const { return propProgress;}
void setProgress(int value)
{
propProgress = value;
int index = 0;
for (QGraphicsEllipseItem* ellipse: ellipses)
{
// Keep value between 0 and length.
int lgt = (propProgress + index * 40) % int(path.path().length());
qreal percent = path.path().percentAtLength(lgt);
++index;
ellipse->setPos(path.path().pointAtPercent(percent));
}
}
AnimatedEllipses(QPainterPath const& path): QGraphicsObject(), path(path), propProgress(0)
{
qreal pos = 0;
qreal length = path.length();
while (pos < length)
{
qreal percent = path.percentAtLength(pos);
QPointF pointAtPercent = path.pointAtPercent(percent);
pos += 40;
QGraphicsEllipseItem * item = new QGraphicsEllipseItem(-10, -10, 20, 20, this);
item->setPos(pointAtPercent);
ellipses << item;
}
animation = new QPropertyAnimation(this, "progress");
animation->setStartValue(0);
animation->setEndValue(length);
animation->setDuration(10000);
animation->setLoopCount(-1);
animation->start();
QTimer *timer = new QTimer();
connect(timer, SIGNAL(timeout()), this, SLOT(SlotTimeOut()));
timer->start(1000);
}
void SlotTimeOut() {
int newDuration = GetRandomDuration();
animation->setDuration(newDuration);
}
// QGraphicsItem interface
public:
QRectF boundingRect() const { return path.boundingRect();}
void paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget){}
};
You can do this with custom QEasingCurve. Here is a small example for progressbar value.
MainWindow.h
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
private slots:
void OnChangeDurationTimer();
private:
Ui::MainWindow *ui;
QPropertyAnimation m_animProgress;
};
Initialization
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
m_animProgress.setTargetObject(ui->progressBar);
m_animProgress.setPropertyName("value");
m_animProgress.setStartValue(0);
m_animProgress.setEndValue(100);
m_animProgress.setDuration(10000);
m_animProgress.setLoopCount(-1);
//setting custom QEasingCurve
QEasingCurve eCurve;
eCurve.setCustomType(myEasingFunction);
m_animProgress.setEasingCurve(eCurve);
m_animProgress.start();
QTimer::singleShot(3000, this, &MainWindow::OnChangeDurationTimer); //timer to change duration
}
Most interesting is function myEasingFunction for custom EasingCurve
qreal g_offset = 0; //value last animation stopped with
qreal g_offsetLast = 0; //keep current value of animation
qreal myEasingFunction(qreal progress)
{
qreal val = g_offset + progress;
while (val > 1) {
val -= 1; //normalize
}
g_offsetLast = val;
return val;
}
And changing duration on timer
void MainWindow::OnChangeDurationTimer()
{
g_offset = g_offsetLast; //remember stopped value
m_animProgress.stop();
m_animProgress.setDuration((rand() % 10 + 1) * 1000);
m_animProgress.start();
QTimer::singleShot(3000, this, &MainWindow::OnChangeDurationTimer); //next changing
}
I have a bunch of ellipses that initially are lined on top of a path and should move along the QPainterPath. I have it working for the first ellipse but I can't figure out how to get the correct position for the other ellipses.
Is there a way to check if it passed the end of the path and move it back to the beginning?
class Animation : public QAbstractAnimation
{
public:
Animation(const QPainterPath& path, QObject *parent = Q_NULLPTR);
virtual void updateCurrentTime(int ms) override;
virtual int duration() const override;
QPainterPath mPath;
QVector<EllipseGraphicsItem*> mAnimationElements;
};
Animation::Animation (const QPainterPath& path, QObject *parent) : QAbstractAnimation(parent)
, mPath(path)
{
qreal pos = 0;
qreal length = mPath.length();
while (pos < length)
{
qreal percent = path.percentAtLength(pos);
QPointF pointAtPercent = path.pointAtPercent(percent);
pos += 40;
EllipseGraphicsItem * item = new EllipseGraphicsItem(parentItem());
mAnimationElements.append(item);
item->setPos(pointAtPercent);
}
}
void Animation::updateCurrentTime(int ms)
{
QPointF point = mPath.pointAtPercent(qreal(ms) / 6000);
if (mAnimationElements.size() > 0)
mAnimationElements[0]->setPos(point);
for (int i = 0; i < mAnimationElements.size(); i++) {
// how to update each circle's position?
}
}
Start the animation:
QPainterPath path;
path.moveTo(10, 10);
path.lineTo(QPointF(500, 10));
path.lineTo(QPointF(500, 700));
path.lineTo(QPointF(10, 700));
Animation *animation = new Animation(path, this);
animation->setLoopCount(-1);
animation->start();
Imho, it would be easier to use a QGraphicsObject with a QPropertyAnimation:
Use a property that varies between 0 and the length of the path and place your elements by calculating their positions from its value and their position in the list.
A quick example :
class AnimatedEllipses: public QGraphicsObject
{
Q_OBJECT
Q_PROPERTY(int progress READ progress WRITE setProgress)
private:
QGraphicsPathItem path;
QList<QGraphicsEllipseItem*> ellipses;
int propProgress;
public:
int progress() const { return propProgress;}
void setProgress(int value)
{
propProgress = value;
int index = 0;
for (QGraphicsEllipseItem* ellipse: ellipses)
{
// Keep value between 0 and length.
int lgt = (propProgress + index * 40) % int(path.path().length());
qreal percent = path.path().percentAtLength(lgt);
++index;
ellipse->setPos(path.path().pointAtPercent(percent));
}
}
AnimatedEllipses(QPainterPath const& path): QGraphicsObject(), path(path), propProgress(0)
{
qreal pos = 0;
qreal length = path.length();
while (pos < length)
{
qreal percent = path.percentAtLength(pos);
QPointF pointAtPercent = path.pointAtPercent(percent);
pos += 40;
QGraphicsEllipseItem * item = new QGraphicsEllipseItem(-10, -10, 20, 20, this);
item->setPos(pointAtPercent);
ellipses << item;
}
QPropertyAnimation* animation = new QPropertyAnimation(this, "progress");
animation->setStartValue(0);
animation->setEndValue(length);
animation->setDuration(10000);
animation->setLoopCount(-1);
animation->start();
}
// QGraphicsItem interface
public:
QRectF boundingRect() const { return path.boundingRect();}
void paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget){}
};
The modulo allows you to create an infinte loop for each ellipse.
I have already used
setOpacity();
setAttribute(Qt:WA_TranseculentBackground:)
even i have tied all the available solution nothing has effect.
this is my code
void Physician::mouseMoveEvent(QMouseEvent *e)
{
rubberBand->hide();
bottomRight = e->pos();
QRect rect = QRect(topLeft, bottomRight);
rubberBand->setGeometry(rect);//Area Bounding
QToolTip::showText(e->globalPos(), QString("%1,%2")
.arg(rubberBand->size().width())
.arg(rubberBand->size().height()), this);
}
void Physician::mousePressEvent(QMouseEvent *e)
{
rubberBand->hide();
if(e->x()<ui->videoShowLabel->x()||e->y()<ui->videoShowLabel->y())
{
selectWithInLabel.critical(0,"Error", "Select within the LABEL !");
selectWithInLabel.setFixedSize(500, 200);
}
else{
topLeft = e->pos();
myPoint = ui->videoShowLabel->mapFromGlobal(this->mapToGlobal(e->pos()));
}
}
void Physician::mouseReleaseEvent(QMouseEvent *e){
rubberBand->setWindowOpacity(0.5);
rubberBand->show();
}
void Physician::on_manualROIRadioButton_clicked()
{
rubberBand = new RubberBand(RubberBand::Rectangle, this);
}
What should i do to make rubberBand semiTransparent
I assume you sub classed QRubberBand (RubberBand).
After calling the setWindowopacity the paint event is generated (http://doc.qt.io/qt-5/qwidget.html#windowOpacity-prop)
So redefine the paint event in RubberBand class.
Inside the paint event call "initStyleOption" (given below)
http://doc.qt.io/qt-5/qrubberband.html#initStyleOption
By calling "initStyleOption" you can set the rubber band parameters for drawing.
The real issue with making the QRubberband semi-transparent is that mplayer is painting on a window without Qt having any knowledge of it. Hence Qt itself cannot act as a compositor to generate the required effect.
One possibility would be to make the QRubberBand a top level window. That way the compositing is the responsibility of the underlying graphics system rather than Qt.
With that in mind try the following. Firstly a utility base class to manage the geometry...
class abstract_rubber_band {
public:
virtual QRect get_geometry () const
{
return(QRect(m_parent->mapFromGlobal(widget().geometry().topLeft()), widget().size()));
}
virtual void set_geometry (const QRect &rect)
{
widget().setGeometry(map_rect(rect));
}
protected:
explicit abstract_rubber_band (QWidget *parent)
: m_parent(parent)
{}
/*
* #param point Coords relative to effective parent.
*/
QPoint map_point (QPoint point) const
{
if (point.x() < 0)
point.rx() = 0;
else if (point.x() >= m_parent->width())
point.rx() = m_parent->width() - 1;
if (point.y() < 0)
point.ry() = 0;
else if (point.y() >= m_parent->height())
point.ry() = m_parent->height() - 1;
point = m_parent->mapToGlobal(point);
return(point);
}
QRect map_rect (QRect rect) const
{
return(QRect(map_point(rect.topLeft()), map_point(rect.bottomRight())));
}
private:
QWidget &widget ()
{
return(dynamic_cast<QWidget &>(*this));
}
const QWidget &widget () const
{
return(dynamic_cast<const QWidget &>(*this));
}
QWidget *m_parent;
};
Now use the above as a base of the required rubber band class...
class rubber_band: public abstract_rubber_band,
public QRubberBand {
using super = QRubberBand;
public:
/*
* #param parent Note that this isn't actually used as the
* parent widget but rather the widget to which
* this rubber_band should be confined.
*/
explicit rubber_band (QWidget *parent)
: abstract_rubber_band(parent)
, super(QRubberBand::Rectangle)
{
setAttribute(Qt::WA_TranslucentBackground, true);
}
protected:
virtual void paintEvent (QPaintEvent *event) override
{
QPainter painter(this);
painter.fillRect(rect(), QColor::fromRgbF(0.5, 0.5, 1.0, 0.25));
QPen pen(Qt::green);
pen.setWidth(5);
painter.setPen(pen);
painter.setBrush(Qt::NoBrush);
painter.drawRect(rect().adjusted(0, 0, -1, -1));
/*
* Display the current geometry in the top left corner.
*/
QRect geom(get_geometry());
painter.drawText(rect().adjusted(5, 5, 0, 0),
Qt::AlignLeft | Qt::AlignTop,
QString("%1x%2+%3+%4").arg(geom.width()).arg(geom.height()).arg(geom.left()).arg(geom.top()));
}
};
The above rubber_band class should almost be a drop in replacement for QRubberBand. The main difference is that rather than reading/writing its geometry with geometry/setGeometry you must use get_geometry/set_geometry -- those will perform the mapping to/from global coordinates.
In your particular case create the rubber_band with...
rubberBand = new rubber_band(ui->videoShowLabel);
I would like to create coordinate points on a QGraphicsView. When the mouse hovers over the point, the coordinate will be shown.
I draw the coordinates by QGraphicsEllipseItem. In order to enable the hover event, I need to re-implement the QGraphicsEllipseItem. However, because the size of the QGraphicsEllipseItem is fixed when it was constructed, the hover text is not shown properly. How can I deal with this?
Here is my code:
The MainWindow:
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
{
view = new QGraphicsView(this);
view->setRenderHint(QPainter::Antialiasing);
scene = new QGraphicsScene(this);
view->fitInView(scene->sceneRect(), Qt::KeepAspectRatio);
view->setScene(scene);
setCentralWidget(view);
for (int y = 0; y < 900; y += 100)
for(int x = 0; x < 1400; x += 100)
drawPoint(x, y);
}
void MainWindow::drawPoint(int x, int y)
{
CoordinatePoint* point = new CoordinatePoint();
point->setRect(QRect(x, y, 3, 3));
point->setPen(QPen(Qt::red, 3, Qt::SolidLine));
point->setBrush(Qt::red);
scene->addItem(point);
}
The re-implement QGraphicsEllipseItem:
CoordinatePoint::CoordinatePoint(QGraphicsItem* parent)
:QGraphicsEllipseItem(parent)
{
setAcceptHoverEvents(true);
}
void CoordinatePoint::hoverEnterEvent(QGraphicsSceneHoverEvent* event)
{
hover = true;
mx = event->pos().x();
my = event->pos().y();
update();
}
void CoordinatePoint::hoverLeaveEvent(QGraphicsSceneHoverEvent* event)
{
hover = false;
update();
}
void CoordinatePoint::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
{
QGraphicsEllipseItem::paint(painter, option, widget);
if (hover)
{
painter->save();
painter->setPen(Qt::black);
painter->setBrush(Qt::black);
painter->drawText(mx + 2, my + 2,
"(" + QString::number(mx) + "," +
QString::number(my) + ")");
painter->restore();
}
}
I think that using a separate child item for the text will make your life a lot easier:
#include <QtWidgets>
class CoordinatePoint : public QGraphicsEllipseItem
{
public:
CoordinatePoint(QGraphicsItem* parent = Q_NULLPTR) :
QGraphicsEllipseItem(parent),
coordinateText(Q_NULLPTR)
{
setAcceptHoverEvents(true);
}
void hoverEnterEvent(QGraphicsSceneHoverEvent*)
{
if (!coordinateText) {
coordinateText = new QGraphicsTextItem(this);
coordinateText->setPlainText("(" + QString::number(x())
+ "," + QString::number(y()) + ")");
coordinateText->setX(2);
coordinateText->setY(2);
}
coordinateText->setVisible(true);
}
void hoverLeaveEvent(QGraphicsSceneHoverEvent*)
{
if (coordinateText) {
coordinateText->setVisible(false);
}
}
private:
QGraphicsTextItem *coordinateText;
};
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QMainWindow window;
QGraphicsView *view = new QGraphicsView(&window);
view->setRenderHint(QPainter::Antialiasing);
QGraphicsScene *scene = new QGraphicsScene(&window);
view->fitInView(scene->sceneRect(), Qt::KeepAspectRatio);
view->setScene(scene);
window.setCentralWidget(view);
for (int y = 0; y < 900; y += 100) {
for(int x = 0; x < 1400; x += 100) {
CoordinatePoint* point = new CoordinatePoint();
point->setRect(QRect(0, 0, 3, 3));
point->setX(x);
point->setY(y);
point->setPen(QPen(Qt::red, 3, Qt::SolidLine));
point->setBrush(Qt::red);
scene->addItem(point);
}
}
window.show();
return a.exec();
}
If having an extra QGraphicsTextItem for each coordinate worries you, you could construct one of them and just share it amongst them all, reparenting it as each one is hovered. This should work fine, as there can only ever be one coordinate hovered at a time.
If you try to draw the text as part of the ellipse item, you'd have to:
Increase the size of the item so that it's large enough to contain the text, which means overriding boundingRect().
Only draw the ellipse within a certain part of that area.
In hoverEnterEvent(), check that the mouse cursor is within the ellipse's area.
A bunch of other stuff, probably.
I am implementing undo/redo for move operation on QGraphicsItemGroup in my graphics scene. It works decently for point entity.
My command for move looks like:
class CommandMove : public QUndoCommand
{
public:
CommandMove(QGraphicsItemGroup *group, qreal fromX, qreal fromY,
qreal toX, qreal toY)
{
itemGroup = group;
mFrom = QPointF(fromX, fromY);
mTo = QPointF(toX, toY);
setText(QString("Point move (%1,%2) -> (%3,%4)").arg(fromX).arg(fromY)
.arg(toX).arg(toY));
}
virtual void undo()
{
itemGroup->setPos(mFrom);
}
virtual void redo()
{
itemGroup->setPos(mTo);
}
private:
QGraphicsItemGroup *itemGroup;
QPointF mFrom;
QPointF mTo;
};
My command is pushed to the undo stack as:
if (item.first->scenePos() != item.second)
{
mUndoStack->push(new CommandMove(item.first, item.second.x(),
item.second.y(), item.first->x(),
item.first->y()));
}
item is a QPair defined as:
typedef QPair<QGraphicsItemGroup *, QPointF> item;
Implemenatation for entities like line, circle etc. requires more information as compared to point. eg., start and end points for line. How do I define my command for moving my entities?
Edit
This is my implementation for line:
if (m1)
{
start_p = event->scenePos();
m1 = false;
m2 = true;
}
else if (!m1 && m2)
{
end_p = event->scenePos();
m3 = true;
m2 = false;
}
if (m3)
{
lineItem = new Line(start_p, end_p);
}
Here event is mousePressEvent.
Where do I use setPos to set the position of line?
I think you shouldn't care about all item's peculiarities. You can implement a move command that works well for any item or group of items. This is a modified version of your code.
class CommandMove : public QUndoCommand
{
public:
CommandMove(QGraphicsItem *item, qreal toX, qreal toY)
{
mItem = item;
mFrom = mItem->pos();
mTo = QPointF(toX, toY);
setText(QString("Point move (%1,%2) -> (%3,%4)").arg(mFrom.x()).arg(mFrom.y())
.arg(mTo.x()).arg(mTo,y()));
}
virtual void undo()
{
mItem->setPos(mFrom);
}
virtual void redo()
{
mItem->setPos(mTo);
}
private:
QGraphicsItem* mItem;
QPointF mFrom;
QPointF mTo;
};
I hope this helps.