Draw floating UILayout

Question

In sculpt mode you get this menu with a right click:

The UI elements in this menu are visually the same you would get by drawing a UI using bpy.types.UILayout functions. Yet, the only answers I found for drawing custom floating UI elements referred to bgl and blf, like in these two Blender StackExchange questions:

1. How to draw shapes in the node editor with python bgl
2. Floating UI window in 3D view

However, ideally I would use standard Blender UI elements to create something like that. Is there a way to draw standard Blender UI elements in floating windows like those in the screenshot using Python?

Answer 1

WindowManager.invoke_props_popup(operator, event)

Operator popup invoke (show operator properties and execute it automatically on changes)

Code based on How to call a confirmation dialog box?, I just replaced invoke_props_dialog by invoke_props_popup to diplay the popup without confirmation option:

import bpy
class SimplePropConfirmOperator(bpy.types.Operator):
    """Really?"""
    bl_idname = "my_category.custom_confirm_dialog"
    bl_label = "Do you really want to do that?"
    bl_options = {'REGISTER', 'UNDO'}
prop1: bpy.props.BoolProperty()
prop2: bpy.props.BoolProperty()

@classmethod
def poll(cls, context):
    return True

def execute(self, context):
    self.report({'INFO'}, "YES!")
    return {'FINISHED'}

def invoke(self, context, event):
    return context.window_manager.invoke_props_popup(self, event)

def draw(self, context):
    row = self.layout
    row.prop(self, "prop1", text="Property A")
    row.prop(self, "prop2", text="Property B")



class OBJECT_PT_CustomPanel(bpy.types.Panel):
    bl_label = "My Panel"
    bl_idname = "OBJECT_PT_custom_panel"
    bl_space_type = "VIEW_3D"

    bl_region_type = "UI"
    bl_category = "Tools"
    bl_context = "objectmode"
def draw(self, context):
    layout = self.layout
    layout.operator(SimplePropConfirmOperator.bl_idname)


def register():
    bpy.utils.register_class(OBJECT_PT_CustomPanel)
    bpy.utils.register_class(SimplePropConfirmOperator)
def unregister():
    bpy.utils.unregister_class(SimplePropConfirmOperator)
    bpy.utils.unregister_class(OBJECT_PT_CustomPanel)
if name == "main":
    register()