[Moved] PyQt - Mouse events on GraphicsItems inside a GraphicsScene/GraphicsView



  • 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(QtGui.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.

    Any advice on how to make this work?



  • 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.


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