* Disable warning of subprocess launched by dataloader

* Add type hint

* dataset tutorial abstract

* complete dataloader & dataset tutorial

* minor fix

* minor fix

* resolve comments

* rename some link to be more specific

* add warning to manually constructed sampler

* fix as comments

* [Refactor]: modify interface of Visualizer.add_datasample (#365)

* [Refactor] Refactor data flow: refine `data_preprocessor`. (#359)

* refine data_preprocessor

* remove unused BATCH_DATA alias

* Fix type hints

* rename move_data to cast_data

* [Refactor] Refactor data flow: collate data in `collate_fn` of `DataLoader`  (#323)

* acollate data in dataloader

* fix docstring

* refine comment

* fix as comment

* refactor default collate and psedo collate

* foramt test file

* fix docstring

* fix as comment

* rename elem to data_item

* minor fix

* fix as comment

* [Refactor] Refactor data flow: `data_batch` argument of `Evaluator.process is a `dict` (#360)

* refine evaluator and metric

* compatible with new default collate

* replace default collate with pseudo

* Handle data_batch in metric

* fix unit test

* fix unit test

* fix unit test

* minor refine

* make data_batch optional

make data_batch optional

* rename outputs to predictions

* fix ut

* rename predictions to outputs

* fix docstring

* fix docstring

* fix unit test

* make outputs and data_batch to kwargs

* fix unit test

* keep signature of metric

* fix ut

* rename pred_sample arguments to data_sample(Visualizer)

* fix loop and ut

* [refactor]: Refactor model dataflow (#398)

* [Refactor] Refactor data flow: refine `data_preprocessor`. (#359)

* refine data_preprocessor

* remove unused BATCH_DATA alias

* Fix type hints

* rename move_data to cast_data

* refactor model data flow

tmp_commt

tmp commit

* make val_cfg and test_cfg optional

* roll back runner

* pass test mmdet

* fix as comment

fix as comment

fix ci in DataPreprocessor

* fix ut

* fix ut

* fix rebase main

* [Fix]: Fix test val ddp (#462)

* [Fix] Fix docstring and type hint of data flow (#463)

* Fix docstring of data flow

* change signature of hook

* fix unit test

* resolve conflicts

* fix lint

* Rename data to structure

* adjust the way to import module

* adjust the way to import module

* rename Structure to Data Structures in docs api

* rename structure to structures

* support using some modules of mmengine without torch

* fix circleci config

* fix circleci config

* fix registry ut

* minor fix

* move init method from model/utils to model/weight_init.py

* move init method from model/utils to model/weight_init.py

* move sync_bn to model

* move functions depending on torch to dl_utils

* format import

* fix logging ut

* add weight init in model/__init__.py

* move get_config and get_model to mmengine/hub

* move log_processor.py to mmengine/runner

* fix ut

* Add TimeCounter in dl_utils/__init__.py

* [Refactor] Refactor data_batch type.

* fix sampler

* [Refactor] Remove cur_dataloader in runner.

* fix set_epoch

* [Enhancement] refactor base data elment

* fix comment

* fix comment

* fix pop not existing key without error

* [Feature] Add Runner and Loop

* refine docstring

* refine docstring

* refine __init__ of Runner

* add Runner.save_checkpoint

* add comment for data_batch

* rename validation_cfg to val_cfg

* update branch

* update branch

* discard wear reference

* set seed for torch in dataloader worker

* refine comments

* reorder methods

* import module in __init__.py

* add runner.load_checkpoint

* rename attributes

* fix indent

* fix indent

* add comment for LOOPS

* add example for methods

* add example for methods

* refine examples

* add Runner.resume and refactor register_hooks

* remove type hint of runner in CheckpointHook

* rename before_run to before_train

* remove collate

* add before_run after_run for loop.run

* dummy collate_fn

* add more unit tests

* move call_hook('before_run') to runner

* minor fix

* add comments for collate_fn

* fix type hint

* refactor logic to load or resume checkpoint

* fix typo

* add comments for IterBasedTrainLoop

* refactor unit tests

* fix unit tests

* refactor

* fix setup_env

* refine

* minor fix

* Merge branch 'main' of github.com:open-mmlab/mmengine into zzd/add-runner

* minor fix

* minor fix

* refine

* refactor unit tests

* fix unit tests

* add launcher property

* add logger, message_hub and writer unit tests

* add cur_dataloader attribute for runner

* fix IterBasedTrainLoop

* add torch.no_grad decorator

* add master_only decorator for save_checkpoint

* add before_test_epoch in TestLoop

* refactor load_or_resume method

* refine docstring

* fix typo

* build_dataloader can handle dataset object

* add dump_config for runner

* collate_fn should not a lambda function

* minor fix

* refine docstring

* fix unit tests

* improve comments

* refine unit tests

* rename collate_fn to pseduo_collate

* add 'TODO' tag