如何获取点击 QGraphicsItem 的事件，并收到 focusOut 通知
我有一个从 QGraphicsItem 实现的类，称为 Node。
我有一个矩形“节点”，当用户单击它时我可以执行某些操作，
我使用 mousePress 和 mouseRelease 事件。
但我希望当用户单击“超出”矩形形状时收到通知。
我尝试实现这些功能：
Qt 代码：
void Node::focusInEvent ( QFocusEvent * event){
cout<<"in"<<endl;
update();
QGraphicsItem::focusInEvent(event);
}
void Node::focusOutEvent ( QFocusEvent * event ){
cout<<"out"<<endl;
update();
QGraphicsItem::focusOutEvent(event);
}
void Node::hoverEnterEvent(QGraphicsSceneHoverEvent *event){
cout<<"out"<<endl;
}
如果我单击矩形内或外，这些功能不会做出反应。 我应该自己设置一个逻辑，例如获取鼠标位置并控制它是否超出矩形？ 或者有内置的方法吗？
或者“Node”对象如何知道是否单击了其他 Node 对象？
我也想知道，谷歌搜索但找不到 focusinevent 和 focusoutevent 何时触发？我想当我单击该项目然后单击该项目时， focusOutEvent 必须起作用，我错了吗？
谢谢你的主意。
i have a class implemented from QGraphicsItem, called Node.
i have a rectangle shaped "Node" and i can do something when user clicked on it
i use mousePress and mouseRelease events.
but i want to be notified when user clicked "out of" the rectangle shape.
i tried to implement these functions:
Qt Code:
void Node::focusInEvent ( QFocusEvent * event){
cout<<"in"<<endl;
update();
QGraphicsItem::focusInEvent(event);
}
void Node::focusOutEvent ( QFocusEvent * event ){
cout<<"out"<<endl;
update();
QGraphicsItem::focusOutEvent(event);
}
void Node::hoverEnterEvent(QGraphicsSceneHoverEvent *event){
cout<<"out"<<endl;
}
these do not reacts if i click in or out of rectangle.
should i set a logic on my own for example getting the mouse position and control if it is out of rectangle?
or is there a built in method?
or how can a "Node" object know if other Node object is clicked?
also i wonder, googled but could not found that when does focusinevent and focusoutevent triggered? I guess focusOutEvent must work when i had clicked in the item, then out of the item, am i wrong?
thanks for idea.
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在构建节点时，您需要执行以下操作：
第一行使您的项目实际上能够接收焦点，而后者使您的项目能够收到鼠标事件的通知。
You need to do the following when you construct your nodes:
The first line makes your item actually capable of receiving focus, and the latter makes it so your item is notified of mouse events.
您是否使用 QGraphicsItem 调用了图形项目的 setFlags 方法： :ItemIsSelectable 或 QGraphicsItem::ItemIsMovable ？
根据 QT 文档。
Have you called setFlags method of your graphics item with QGraphicsItem::ItemIsSelectable or QGraphicsItem::ItemIsMovable ?
According to QT doc.