I am trying to connect to the mouse-enter event of QGraphicsItems that are placed onto a QGraphicsScene and visualized through a QGraphicsView. From what I understand, the method to override for this is dragEnterEvent in a class derived from QGraphicsItem (or one of it's subclasses). My attempt looks like this:
class StaPoly(QtGui.QGraphicsPolygonItem):
def __init__(self,*args):
QtGui.QGraphicsPolygonItem.__init__(self,*args)
self.setAcceptDrops(True)
def dragEnterEvent(self,event):
print "Enter!"
...
def draw(self):
p = self.parent
self.group = QtGui.QGraphicsItemGroup(scene=p.scene)
...
for xpix in lons:
poly = QtGui.QPolygonF()
poly << QtCore.QPointF(xpix-symw,ypix)
poly << QtCore.QPointF(xpix,ypix+symh)
poly << QtCore.QPointF(xpix+symw,ypix)
poly << QtCore.QPointF(xpix,ypix-symh)
item = StaPoly(poly)
item.setPen(Qt开发者_如何学运维Gui.QColor(color))
item.setBrush(QtGui.QColor(color))
self.group.addToGroup(item)
I hope the above snippets make it clear what I am trying to do. Note that the display is generated exactly as I desire, no issue there - however the polygons that get drawn are not responding to the enter-event - I am not seeing any evidence that dragEnterEvent() is being called.
The (partial) solution was this:
self.group.setHandlesChildEvents(False)
This ensures that individual items handle their own events, it seems that before the group was capturing them.
I still have a problem in that my GraphicsView overrides the mouseMoveEvent, and when enabled, no events get propagated to scene items.
EDIT: And it seems the solution to this second problem was to call the base class mouseMoveEvent handler from the Views mouseMoveEvent handler e.g.
def mouseMoveEvent(self,event):
QtGui.QGraphicsView.mouseMoveEvent(self, event)
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