c++ - Qt QXYSeries 和 ChartView - 修改悬停行为以在一个范围内触发

Question

我有一个由 QXYSeries 表示的散点图，并使用 Qt Charts 5.7 中的 ChartView 查看。

我想将鼠标悬停在绘图上，在一定距离内“悬停”触发，而不是仅当我的光标直接位于点上方时。想象鼠标周围有一个圆圈，只要系列的任何部分位于其中，就会触发悬停。

有没有办法获得这种行为？

Answer 1

最终，我通过创建一个继承自 QChartView 的类并重写 mouseMoveEvent(QMouseEvent* event) 实现了这种行为:

void ScatterView::mouseMoveEvent(QMouseEvent* event)
{
    if(!this->chart()->axisX() || !this->chart()->axisY())
    {
        return;
    }
    QPointF inPoint;
    QPointF chartPoint;
    inPoint.setX(event->x());
    inPoint.setY(event->y());
    chartPoint = chart()->mapToValue(inPoint);
    handleMouseMoved(chartPoint);
}

void ScatterView::handleMouseMoved(const QPointF &point)
{
    QPointF mousePoint = point;
    qreal distance(0.2); //distance from mouse to point in chart axes
    foreach (QPointF currentPoint, scatterSeries->points()) { 
        qreal currentDistance = qSqrt((currentPoint.x() - mousePoint.x())
                                      * (currentPoint.x() - mousePoint.x())
                                      + (currentPoint.y() - mousePoint.y())
                                      * (currentPoint.y() - mousePoint.y()));
        if (currentDistance < distance) {
            triggerPoint(currentPoint);
        }
    }
}