Issues trying to disable dragging of the buttons

ConfusedProgrammer

Hello everybody,

I made a Button class that inherits QGraphicsRectItem in order to have the button to be draggable accross the view. A button object is the added to a scene and it allows me to drag the buttons just like I want.

My problem is that I want to be able to disable the dragging from a menu action item.

I tried to make a method on the button class that will simply toggle the flag : self.setFlag(QGraphicsItem.ItemIsMovable, False)

However when I use the method when I stored the objects in a list it results with this error.

AttributeError: 'NoneType' object has no attribute 'disable_dragbuttons'

Could anybody point me in the right direction?

Something to consider I am using Python with PySide2.

SGaist

Hi,

Can you show how you create these buttons and how to you put them it that list ?

ConfusedProgrammer

Yes I will, I am using python though. Here is the code.

class Button(QGraphicsRectItem):
    def __init__(self, text, *args): 
         QGraphicsRectItem.__init__(self, *args)
         #allows buttons to be dragged
         self.setFlag(QGraphicsItem.ItemIsMovable, True)

      def disable_button_drag(self):
            self.setFlag(QGraphicsItem.ItemIsMovable, True)  #disable dragging

#Adding 10 buttons to list and at scene 
def load_buttons(self):
      self.buttons = [self.scene.addItem(Button("name",coords)) for i in range(10)]

This results in 10 buttons drawn at the QGraphicsView and are draggable. Issue is that I cant modify the buttons afterward because of the Nonetype error.

SGaist

What do you get if you print(self.buttons) after calling load_buttons ?

ConfusedProgrammer

@SGaist

Hi I get a NoneType.

I found the issue turns out that I am calling a method inside that array. <doh!>

I did this now and it works.

def load_buttons(self):
   self.buttons = [Button(name,coords) for i in range(10)]
   
   for button in buttons:
          self.scene.addItem(button)
          print(button)

Now instead of printing None it now prints an object address.

After doing this the buttons now work as intended.

Thank you guys, you are really good.