问题描述
我在Qt和C ++上还很陌生。我有一个具有QLineSeries对象的QChart。我想向用户展示鼠标在坐标系上的投影。我的问题是我可以在除QChart对象之外的任何地方显示坐标。我只想将鼠标放在QChart上才能显示坐标。这是我的代码示例:
boxWhisker.h文件
QGraphicsSimpleTextItem *m_coordX;
QGraphicsSimpleTextItem *m_coordY;
QChart *chartTrendLine;
QChartView *trendLineChartView;
QLineSeries *trendLine;
boxWhisker.cpp文件
this->chartTrendLine = new QChart();
this->chartTrendLine->addSeries(this->trendLine);
this->chartTrendLine->legend()->setVisible(true);
this->chartTrendLine->createDefaultAxes();
this->chartTrendLine->setAcceptHoverEvents(true);
this->trendLineChartView = new QChartView(this->chartTrendLine);
this->trendLineChartView->setRenderHint(QPainter::Antialiasing);
this->m_coordX = new QGraphicsSimpleTextItem(this->chartTrendLine);
this->m_coordX->setPos(this->chartTrendLine->size().width()/2+50,this->chartTrendLine->size().height());
this->m_coordY = new QGraphicsSimpleTextItem(this->chartTrendLine);
this->m_coordY->setPos(this->chartTrendLine->size().width()/2+100,this->chartTrendLine->size().height());
void boxWhiskerDialog::mouseMoveEvent(QMouseEvent *mouseEvent)
{
this->m_coordY->setText(QString("Y: %1").arg(this->chartTrendLine->mapToValue(mouseEvent->pos()).y()));
this->m_coordX->setText(QString("X: %1").arg(this->chartTrendLine->mapToValue(mouseEvent->pos()).x()));
}
我的问题是如何仅在QChart上显示坐标?任何帮助将不胜感激!
编辑
在这里,我尝试创建一个由QChart类继承的新类,并在新类中定义mouseEvent函数。这是我的代码示例:
qchart_me.h:
class QChart_ME : public QT_CHARTS_NAMESPACE::QChart
{
public:
QChart_ME();
protected:
void mouseMoveEvent(QGraphicsSceneMouseEvent *event);
private:
QGraphicsSimpleTextItem *m_coordX;
QGraphicsSimpleTextItem *m_coordY;
QChart *m_chart;
};
qchart_me.cpp:
QChart_ME::QChart_ME()
{
}
void QChart_ME::mouseMoveEvent(QGraphicsSceneMouseEvent *Myevent)
{
m_coordX->setText(QString("X: %1").arg(m_chart->mapToValue(Myevent->pos()).x()));
m_coordY->setText(QString("Y: %1").arg(m_chart->mapToValue(Myevent->pos()).y()));
}
boxWhisker.h:
QChart_ME *chartTrendLine;
boxWhisker.cpp
this->chartTrendLine = new QChart_ME();
this->chartTrendLine->addSeries(this->trendLine);
this->chartTrendLine->legend()->setVisible(true);
this->chartTrendLine->createDefaultAxes();
this->chartTrendLine->setAcceptHoverEvents(true);
QGraphicsSceneMouseEvent *myEvent;
this->chartTrendLine->mouseMoveEvent(myEvent);
我试图编辑我的代码,例如Qt标注示例。
我得到的错误:
在此上下文中保护了'virtual void QChart_ME :: mouseMoveEvent(QGraphicsSceneMouseEvent *)'
this-> chartTrendLine-> mouseMoveEvent(myEvent);
我该如何解决这个问题?
解决方法
原因
您正在为Error: Process 'docker exec -i "myapp...' exited with code 1
Error: Error: No such container: myapp
类而不是boxWhiskerDialog
获得鼠标事件。
解决方案
子类QChart
并重新实现其QChart
,而不是重新实现mouseMoveEvent
。