spinetoolbox.spine_db_editor.mvcmodels.multi_db_tree_item

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

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, db_map_ids=None)

Bases: spinetoolbox.mvcmodels.minimal_tree_model.TreeItem

A tree item that may belong in multiple databases.

Parameters

• model (MinimalTreeModel, optional) – item’s model

• db_map_ids (dict, optional) – maps instances of DatabaseMapping to the id of the item in that db

property visible_children

property db_mngr

abstract property child_item_class

Returns the type of child items.

property display_id

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 name

property display_data

Returns the name for display.

property display_database

Returns the database for display.

property display_icon

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

property first_db_map

Returns the first associated db_map.

property db_maps

Returns a list of all associated db_maps.

property db_map_ids

Returns dict with db_map as key and id as value

property _children_sort_key

property fetch_item_type

item_type

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

visual_key = ['name']

_fetch_index

row_count()

Overriden to use visible_children.

child(row)

Overriden to use visible_children.

child_number()

Overriden to use find_row which is a dict-lookup rather than a list.index() call.

refresh_child_map()

Recomputes the child map.

abstract set_data(column, value, role)

Sets data for this item.

Parameters

• column (int) – column index

• value (object) – a new value

• role (int) – role of the new value

Returns

True if data was set successfully, False otherwise

Return type

bool

add_db_map_id(db_map, id_)

Adds id for this item in the given db_map.

take_db_map(db_map)

Removes the mapping for given db_map and returns it.

deep_refresh_children()

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

deep_remove_db_map(db_map)

Removes given db_map from this item and all its descendants.

deep_take_db_map(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(other)

Merges another item and all its descendants into this one.

db_map_id(db_map)

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

db_map_data(db_map)

Returns data for this item in given db_map or an empty dict if not present.

db_map_data_field(db_map, field, default=None)

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

_create_new_children(db_map, children_ids, **kwargs)

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

Returns

new children

Return type

list of MultiDBTreeItem

make_or_restore_child(db_map, id_, **kwargs)

Makes or restores a child if one was ever made using given db_map and id. The purpose of restoring is to keep using the same FetchParent, which is useful in case the user undoes a series of removal operations that would add items in cascade to the tree.

Parameters

• db_map (DatabaseMapping) –

• id (int) –

Returns

MultiDBTreemItem

restore(db_map_ids, **kwargs)

_make_child(db_map_ids, **kwargs)

_merge_children(new_children)

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

_insert_children_sorted(new_children)

Inserts and sorts children.

can_fetch_more()

Returns whether this item can fetch more.

fetch_more()

Fetches children from all associated databases.

fetch_more_if_possible()

_key_for_index(db_map)

accepts_item(item, db_map)

handle_items_added(db_map_data)

handle_items_removed(db_map_data)

handle_items_updated(db_map_data)

append_children_by_id(db_map_ids, **kwargs)

Appends children by id.

Parameters

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

remove_children_by_id(db_map_ids)

Removes children by id.

Parameters

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

is_valid()

See base class.

update_children_by_id(db_map_ids, **kwargs)

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(position, children)

Inserts new children at given position.

Parameters

• position (int) – insert new items here

• children (Iterable of MultiDBTreeItem) – insert items from this iterable

Returns

True if children were inserted successfully, False otherwise

Return type

bool

remove_children(position, count)

Removes count children starting from the given position.

reposition_child(row)

find_row(db_map, id_)

find_children_by_id(db_map, *ids, reverse=True)

Generates children with the given ids in the given db_map. If the first id is None, then generates all children with the given db_map.

find_rows_by_id(db_map, *ids, reverse=True)

_find_unsorted_rows_by_id(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(column, role=Qt.ItemDataRole.DisplayRole)

Returns data for given column and role.

default_parameter_data()

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

tear_down()

Do stuff after the item has been removed.

register_fetch_parent()

Registers item’s fetch parent for all model’s databases.