spinetoolbox.spine_db_editor.mvcmodels.multi_db_tree_item

Base classes to represent items from multiple databases in a tree.

authors

16. Vennström (VTT), M. Marin (KTH)

date

17.6.2020

Module Contents

Classes

MultiDBTreeItem

A tree item that may belong in multiple databases.

class spinetoolbox.spine_db_editor.mvcmodels.multi_db_tree_item.MultiDBTreeItem(model=None, db_map_id=None)

Bases: spinetoolbox.mvcmodels.minimal_tree_model.TreeItem

A tree item that may belong in multiple databases.

Init class.

Parameters

• db_mngr (SpineDBManager) – a database manager

• db_map_data (dict) – maps instances of DiffDatabaseMapping to the id of the item in that db

item_type

Item type identifier string. Should be set to a meaningful value by subclasses.

visual_key = ['name']

property db_mngr(self)

property child_item_type(self)

Returns the type of child items. Reimplement in subclasses to return something more meaningful.

property display_id(self)

“Returns an id for display based on the display key. This id must be the same across all db_maps. If it’s not, this property becomes None and measures need to be taken (see update_children_by_id).

property display_data(self)

“Returns the name for display.

property display_database(self)

“Returns the database for display.

property display_icon(self)

Returns an icon to display next to the name. Reimplement in subclasses to return something nice.

property first_db_map(self)

Returns the first associated db_map.

property last_db_map(self)

Returns the last associated db_map.

property db_maps(self)

Returns a list of all associated db_maps.

property db_map_ids(self)

Returns dict with db_map as key and id as value

add_db_map_id(self, db_map, id_)

Adds id for this item in the given db_map.

take_db_map(self, db_map)

Removes the mapping for given db_map and returns it.

_deep_refresh_children(self)

Refreshes children after taking db_maps from them. Called after removing and updating children for this item.

deep_remove_db_map(self, db_map)

Removes given db_map from this item and all its descendants.

deep_take_db_map(self, db_map)

Removes given db_map from this item and all its descendants, and returns a new item from the db_map’s data.

Returns

MultiDBTreeItem, NoneType

deep_merge(self, other)

Merges another item and all its descendants into this one.

db_map_id(self, db_map)

Returns the id for this item in given db_map or None if not present.

db_map_data(self, db_map)

Returns data for this item in given db_map or None if not present.

db_map_data_field(self, db_map, field, default=None)

Returns field from data for this item in given db_map or None if not found.

_create_new_children(self, db_map, children_ids)

Creates new items from ids associated to a db map.

Parameters

• db_map (DiffDatabaseMapping) – create children for this db_map

• children_ids (iter) – create children from these ids

_merge_children(self, new_children)

Merges new children into this item. Ensures that each children has a valid display id afterwards.

has_children(self)

Returns whether or not this item has or could have children.

fetch_more(self)

Fetches children from all associated databases.

abstract _get_children_ids(self, db_map)

Returns a list of children ids. Must be reimplemented in subclasses.

append_children_by_id(self, db_map_ids)

Appends children by id.

Parameters

db_map_ids (dict) – maps DiffDatabaseMapping instances to list of ids

remove_children_by_id(self, db_map_ids)

Removes children by id.

Parameters

db_map_ids (dict) – maps DiffDatabaseMapping instances to list of ids

is_valid(self)

Checks if the item is still valid after an update operation.

update_children_by_id(self, db_map_ids)

Updates children by id. Essentially makes sure all children have a valid display id after updating the underlying data. These may require ‘splitting’ a child into several for different dbs or merging two or more children from different dbs.

Examples of problems:

• The user renames an object_class in one db but not in the others –> we need to split

• The user renames an object_class and the new name is already ‘taken’ by another object_class in another db_map –> we need to merge

Parameters

db_map_ids (dict) – maps DiffDatabaseMapping instances to list of ids

insert_children(self, position, *children)

Insert new children at given position. Returns a boolean depending on how it went.

Parameters

• position (int) – insert new items here

• children (iter) – insert items from this iterable

remove_children(self, position, count)

Removes count children starting from the given position.

clear_children(self)

Clear children list.

_refresh_child_map(self)

Recomputes the child map.

find_children_by_id(self, db_map, *ids, reverse=True)

Generates children with the given ids in the given db_map. If the first id is True, then generates all children with the given db_map.

find_rows_by_id(self, db_map, *ids, reverse=True)

_find_unsorted_rows_by_id(self, db_map, *ids)

Generates rows corresponding to children with the given ids in the given db_map. If the only id given is None, then generates rows corresponding to all children with the given db_map.

data(self, column, role=Qt.DisplayRole)

Returns data for given column and role.

default_parameter_data(self)

Returns data to set as default in a parameter table when this item is selected.