Bug in UI Preview

[nnikbin]

In UI Preview mode, running an add-in that adds a toolbar panel to Fusion 360, then stopping the add-in, then running it again creates an empty space in toolbar. Repeating the previous steps adds more and more empty spaces to the toolbar.

For reproducing the bug, please follow the following steps:

1- Enable UI Preview mode (using Preferences > Preview > UI Preview option)

2- Create an add-in using the following code (borrowed from @liujac code here)

3- Run the add-in

4- Stop the add-in

5- Run the add-in again

import adsk.core, adsk.fusion, adsk.cam, traceback

tbPanel = None
def run(context):
    ui = None
    try:
        app = adsk.core.Application.get()
        ui  = app.userInterface
        
        workSpace = ui.workspaces.itemById('FusionSolidEnvironment')
        tbPanels = workSpace.toolbarPanels
        
        global tbPanel
        tbPanel = tbPanels.itemById('NewPanel')
        if tbPanel:
            tbPanel.deleteMe()
        tbPanel = tbPanels.add('NewPanel', 'New Panel', 'SelectPanel', False)
        
        # Empty panel can't be displayed. Add a command to the panel
        cmdDef = ui.commandDefinitions.itemById('NewCommand')
        if cmdDef:
            cmdDef.deleteMe()
        cmdDef = ui.commandDefinitions.addButtonDefinition('NewCommand', 'New Command', 'Demo for new command')
        tbPanel.controls.addCommand(cmdDef)
        
        ui.messageBox('Hello addin')

    except:
        if ui:
            ui.messageBox('Failed:\n{}'.format(traceback.format_exc()))

def stop(context):
    ui = None
    try:
        app = adsk.core.Application.get()
        ui  = app.userInterface
        
        if tbPanel:
            tbPanel.deleteMe()
        
        ui.messageBox('Stop addin')

    except:
        if ui:
            ui.messageBox('Failed:\n{}'.format(traceback.format_exc()))

[keqingsong · Accepted solution]

We have a fix for this - it'll be in the next update!

[nnikbin]

Thank you @keqingsong for the good news!