How to update label in addon UI panel

Coding Python Support
1

Hi there,

I have been working on a Blender script that is meant to pick a from a list of strings and output it to a UI panel via label when an operator button is pressed by the user. However, the label in the panel does not update from whatever it is set to initially when I change the string variable in the code.

How could I go about updating this label or the panel from the script?

2

Do you have a draw() function? You’ll need one for that update to occur. Here’s one way to do it:

class OBJECT_PT_<PanelName>(Panel):
    ...
    @classmethod
    def poll(self,context):
        return context.object is not None

    def draw(self, context):
        layout = self.layout
        scene = context.scene
        subcolumn = layout.column()
        subrow = layout.row(align=True)
        subrow.label(text="<prop_reference>")

Another good option (I like having a Global variable storage class, it makes things a lot easier):

class Globals():
    var = <default value>
    #update var on operator execute()
g =  Globals()

...
class OBJECT_PT_<PanelName>(Panel):
    ...
    @classmethod
    def poll(self,context):
        return context.object is not None

    def draw(self, context):
        layout = self.layout
        scene = context.scene
        subcolumn = layout.column()
        subrow = layout.row(align=True)
        subrow.label(text=g.var)
1 Like
3

Thank you very much for the reply!

I have the draw function for the panel but there is no update after it is initially drawn. Is there a way to redraw all or part of it somehow? Or do I need to define the variables differently?

These are the string variables before they are redefined by the operator:

# strings to output to panel
ideaOutput1 = "default"
ideaOutput2 = "default2"

After the operator button is pressed and the string variables are changed, the output labels do not change:
Screenshot 2022-06-28 183122

The script is meant to select random list items and output them at the bottom there.

4

Hello ! I think you are changing the prop in a local scope which doesnt modify the global one. Would you mind copy pasting the content of your execute method ?

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