QLineSeries不包含itemClicked信号,如何解决
时间: 2024-10-09 07:12:25 浏览: 27
确实,`QLineSeries`本身并不直接提供`itemClicked`信号,但我们可以借助`QGraphicsItem`的行为来间接实现。你可以自定义一个`QGraphicsPathItem`,将直线转换成路径,并重写其`mousePressEvent`和`mouseMoveEvent`来达到类似的效果。
1. **创建自定义图形项**:
创建一个继承自`QGraphicsPathItem`的新类,比如`CustomPathItem`。
```cpp
class CustomPathItem : public QGraphicsPathItem {
public:
explicit CustomPathItem(QLineF line, QObject *parent = nullptr)
: QGraphicsPathItem(parent), m_line(line) {}
void setLine(const QLineF &line) { m_line = line; update(); }
private:
void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override {
painter->drawLine(m_line.p1(), m_line.p2());
}
signals:
void itemClicked(const QPointF &position);
protected:
void mousePressEvent(QGraphicsSceneMouseEvent *event) override {
emit itemClicked(event->pos());
QGraphicsPathItem::mousePressEvent(event);
}
void mouseMoveEvent(QGraphicsSceneMouseEvent *event) override {
if (event->button() == Qt::LeftButton) {
QPointF newPos = event->scenePos();
QPointF oldStart = mapToParent(m_line.p1());
QPointF newStart = newPos;
QPointF newEnd = newPos + QPointF(m_line.dx(), m_line.dy());
// 如果移动不会改变线的方向,则忽略
if (oldStart.y() != newStart.y() || oldStart.x() != newEnd.x()) {
setLine(QLineF(newStart, newEnd));
}
}
QGraphicsPathItem::mouseMoveEvent(event);
}
private:
QLineF m_line;
};
```
2. **添加到场景**:
在`QChart`中,用`CustomPathItem`代替`QLineSeries`并连接信号。
```cpp
CustomPathItem *customPath = new CustomPathItem(lineSeries.line(), chartScene);
// 连接信号
connect(customPath, &CustomPathItem::itemClicked, this, &YourClass::onCustomPathClicked);
// 添加到图表场景
chartScene.addItem(customPath);
```
现在,当你点击`CustomPathItem`时,它会发出`itemClicked`信号,你可以在`onCustomPathClicked`槽函数中处理后续操作。
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