ObjectClassesList

Introduction

ObjectClassesList is a widget that allows users to view a list of all given object classes. The widget provides a flexible display option with a choice of single-column or multiple-column layouts. It also allows users to select or deselect one or more classes, making it easy to manage and organize object classes. This widget is a useful tool for visualizing and selecting classes in Supervisely.

Function signature

obj_classes_list = ObjectClassesList(
    object_classes=project_meta.obj_classes,
    selectable=False,
    columns=1,
    widget_id=None
)

objclass-list-default

Parameters

Parameters	Type	Description
object_classes	Union[ObjClassCollection, List[ObjClass]]	Supervisely object class collection or list of object classes
selectable	bool	Enable classes selection
columns	int	Number of columns
widget_id	str	ID of the widget

object_classes

Supervisely object class collection (ObjClassCollection) or list of ObjClass.

type: Union[ObjClassCollection, List[ObjClass]]

obj_classes_list = ObjectClassesList(
    object_classes=project_meta.obj_classes
)

selectable

Enable classes selection.

type: bool

default False

obj_classes_list = ObjectClassesList(
    object_classes=project_meta.obj_classes,
    selectable=True
)

objclass-list

columns

Number of columns.

type: int

default 1

obj_classes_list = ObjectClassesList(
    object_classes=project_meta.obj_classes,
    columns=2
)

objclass-list-columns

widget_id

ID of the widget.

type: str

default value: None

Methods and attributes

Attributes and Methods	Description
get_selected_classes()	Return list of selected classes.

Mini App Example

You can find this example in our Github repository:

supervisely-ecosystem/ui-widgets-demos/media/010_object_classes_list/src/main.py

Import libraries

import os
from random import randint

import supervisely as sly
from dotenv import load_dotenv
from supervisely.app.widgets import Button, Card, Container
from supervisely.app.widgets import Image, ObjectClassesList, ProjectThumbnail

Init API client

First, we load environment variables with credentials and init API for communicating with Supervisely Instance:

load_dotenv("local.env")
load_dotenv(os.path.expanduser("~/supervisely.env"))

api = sly.Api()

Initialize Project ID and Dataset ID we will use

project_id = sly.env.project_id()
dataset_id = sly.env.dataset_id()

Get Project info and meta

project_info = api.project.get_info_by_id(id=project_id)

project_meta = sly.ProjectMeta.from_json(api.project.get_meta(project_id))

Initialize ObjectClassesList widget

obj_classes_list = ObjectClassesList(
    object_classes=project_meta.obj_classes,
    selectable=True,
    columns=3,
)

Create app layout

Prepare a layout for app using Card widget with the content parameter and place widget that we've just created in the Container widget.

project_thumbnail = ProjectThumbnail(project_info)

cls_select_btn = Button(text="PREVIEW")

select_class_container = Container(widgets=[obj_classes_list, cls_select_btn])
image = Image()

preview_container = Container(
    widgets=[select_class_container, image],
    direction="horizontal",
    fractions=[2, 1],
)

card = Card(
    title="Object Classes List",
    content=Container(widgets=[project_thumbnail, preview_container]),
)
layout = Container(widgets=[card])

Create app using layout

Create an app object with layout parameter.

app = sly.Application(layout=layout)

Add functions to control widgets from python code

@cls_select_btn.click
def show_info():
    classes = obj_classes_list.get_selected_classes()
    obj_classes = api.object_class.get_list(
        project_id=project_id, filters=[{"field": "name", "operator": "in", "value": classes}]
    )

    imgs = api.image.get_filtered_list(
        dataset_id=dataset_id,
        filters=[{"type": "objects_class", "data": {"classId": obj.id}} for obj in obj_classes],
    )
    if len(imgs) == 0:
        image.clean_up()
        return
    index = randint(0, len(imgs) - 1)
    image.set(imgs[index].full_storage_url)

objclasslist-app