How to setObjectName of the QGraphicsLineItem

Question

I would like to set ObjectName to my LineItem

but when I use

self.line.setItemName('%d' % i)

it is not work and stop the program over there. Can someone tell me how to do? Plz

def createLineItem(self,start,end):

    global i
    i +=1

    self.line = QGraphicsLineItem(QLineF(start, end))
    print("~")
    self.line.setItemName('%d' % i)
    print("~~")
    print( "Line",self.line.objectName())
    self.scene().addItem(self.line)

Answer 1

First of all, where did you get that information that QGraphicsLineItem the setItemName method? QGraphicsLineItem does not have the setItemName method. On the other hand, objectName is a property of the QObjects but QGraphicsLineItem is not. An alternative to save names is to use the data method:

KEY_NAME = 0 

# ...

def createLineItem(self,start,end):
    global i
    i +=1
    line = QGraphicsLineItem(QLineF(start, end))
    line.setData(KEY_NAME, '%d' % i)
    print( "Line", line.data(KEY_NAME))
    self.scene().addItem(line)