Module: Positionable

Defined in:: lib/positionable.rb,
lib/positionable/version.rb

Overview

Positionable is a library which provides contiguous positionning capabilities to your ActiveRecord models. This module is designed to be an ActiveRecord extension.

Calling the is_positionable method in your ActiveRecord model will inject positionning capabilities. In particular, this will guarantee your records’ positions to be contiguous, ie.: there is no ‘hole’ between two adjacent positions.

Positionable has a strong management of records that belong to a group (a.k.a. scope). When a record is moved whithin its scope, or from a scope to another, other impacted records are also reordered accordingly.

You can use the provided instance methods (up!, down! or move_to) to move or reorder your records, whereas it is possible to update the position via mass-assignement. In particular, update_attributes({:position => new_position}) will trigger some ActiveRecord callbacks in order to maintain positions’ contiguity.

Additional methods are available to query your model: check if this the last? or first? of its own scope, retrieve the previous or the next records according to their positions, etc.

Defined Under Namespace

Modules: PositionableMethods Classes: RangeWithoutScopeError

Constant Summary collapse

VERSION =

"1.1.2"

Class Method Summary collapse

.included(base) ⇒ Object

Class Method Details

.included(base) ⇒ `Object`



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# File 'lib/positionable.rb', line 25

def self.included(base)
  base.extend(PositionableMethods)
end