Module: ActiveRecord::Acts::List::InstanceMethods
- Defined in:
- lib/acts_as_list/active_record/acts/list.rb
Overview
All the methods available to a record that has had acts_as_list
specified. Each method works by assuming the object to be the item in the list, so chapter.move_lower
would move that chapter lower in the list of all chapters. Likewise, chapter.first?
would return true
if that chapter is the first in the list of all chapters.
Instance Method Summary collapse
-
#decrement_position ⇒ Object
Decrease the position of this item without adjusting the rest of the list.
-
#first? ⇒ Boolean
Return
true
if this object is the first in the list. -
#higher_item ⇒ Object
Return the next higher item in the list.
-
#in_list? ⇒ Boolean
Test if this record is in a list.
-
#increment_position ⇒ Object
Increase the position of this item without adjusting the rest of the list.
-
#insert_at(position = acts_as_list_top) ⇒ Object
Insert the item at the given position (defaults to the top position of 1).
-
#last? ⇒ Boolean
Return
true
if this object is the last in the list. -
#lower_item ⇒ Object
Return the next lower item in the list.
-
#move_higher ⇒ Object
Swap positions with the next higher item, if one exists.
-
#move_lower ⇒ Object
Swap positions with the next lower item, if one exists.
-
#move_to_bottom ⇒ Object
Move to the bottom of the list.
-
#move_to_top ⇒ Object
Move to the top of the list.
-
#remove_from_list ⇒ Object
Removes the item from the list.
Instance Method Details
#decrement_position ⇒ Object
Decrease the position of this item without adjusting the rest of the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 148 def decrement_position return unless in_list? update_attribute position_column, self.send(position_column).to_i - 1 end |
#first? ⇒ Boolean
Return true
if this object is the first in the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 154 def first? return false unless in_list? self.send(position_column) == acts_as_list_top end |
#higher_item ⇒ Object
Return the next higher item in the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 166 def higher_item return nil unless in_list? acts_as_list_class.find(:first, :conditions => "#{scope_condition} AND #{position_column} = #{(send(position_column).to_i - 1).to_s}" ) end |
#in_list? ⇒ Boolean
Test if this record is in a list
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 182 def in_list? !send(position_column).nil? end |
#increment_position ⇒ Object
Increase the position of this item without adjusting the rest of the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 142 def increment_position return unless in_list? update_attribute position_column, self.send(position_column).to_i + 1 end |
#insert_at(position = acts_as_list_top) ⇒ Object
Insert the item at the given position (defaults to the top position of 1).
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 89 def insert_at(position = acts_as_list_top) insert_at_position(position) end |
#last? ⇒ Boolean
Return true
if this object is the last in the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 160 def last? return false unless in_list? self.send(position_column) == bottom_position_in_list end |
#lower_item ⇒ Object
Return the next lower item in the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 174 def lower_item return nil unless in_list? acts_as_list_class.find(:first, :conditions => "#{scope_condition} AND #{position_column} = #{(send(position_column).to_i + 1).to_s}" ) end |
#move_higher ⇒ Object
Swap positions with the next higher item, if one exists.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 104 def move_higher return unless higher_item acts_as_list_class.transaction do higher_item.increment_position decrement_position end end |
#move_lower ⇒ Object
Swap positions with the next lower item, if one exists.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 94 def move_lower return unless lower_item acts_as_list_class.transaction do lower_item.decrement_position increment_position end end |
#move_to_bottom ⇒ Object
Move to the bottom of the list. If the item is already in the list, the items below it have their position adjusted accordingly.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 115 def move_to_bottom return unless in_list? acts_as_list_class.transaction do decrement_positions_on_lower_items assume_bottom_position end end |
#move_to_top ⇒ Object
Move to the top of the list. If the item is already in the list, the items above it have their position adjusted accordingly.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 125 def move_to_top return unless in_list? acts_as_list_class.transaction do increment_positions_on_higher_items assume_top_position end end |
#remove_from_list ⇒ Object
Removes the item from the list.
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# File 'lib/acts_as_list/active_record/acts/list.rb', line 134 def remove_from_list if in_list? decrement_positions_on_lower_items update_attribute position_column, nil end end |