is an option for Dynamic, DynamicModule, Manipulate, and related constructs that specifies an expression to be evaluated when the construct can no longer be displayed or used.


  • The typical usage is Deinitialization:>expr.
  • Deinitialization is typically done when the cell containing a construct is deleted, or when the notebook containing it is closed.
  • Deinitialization will never be performed unless initialization has previously been performed.
  • Deinitialization may be delayed if, for example, a construct appears in an invisible location such as the clipboard.
  • An object that has been deinitialized can be initialized again if it is restored as a result of using Undo. It may be deinitialized again through the use of Redo or any other action that deletes the object.


open allclose all

Basic Examples  (3)

Choose a color and create the colored disk when the window is closed:

Click for copyable input

Temporarily change the background of a notebook:

Click for copyable input

Track and display how long a window was viewed:

Click for copyable input

Scope  (2)

Properties & Relations  (1)

Neat Examples  (1)

See Also

Initialization  Clear

Introduced in 2007