PackageDescription: RefreshingDisplayPolicy

Refreshing Display Policy

Last published: February 23, 2006 by 'stevek'

Defines 2 Classes
Extends 14 Classes

When a window's process is performing a long-running action, we want it to be unresponsive to user input, but not to damage repair. During these long-running actions, damage repair should be based on the visual state immediately preceeding the current action, since models may be in an unsuitable state for redisplay in the middle of the action. This visual state is stored in the double-buffering pixmap. Windows with other display policies are updated from their models during the long action.

Call 'RefreshingDisplayPolicy usePixmapWhile: aBlock' for long operations, like you might call 'Cursor execute showWhile: aBlock'. Note that aBlock may not open dialogs, or expect any other user input, as all clicks and keypresses will be discarded during aBlock.

This version is for MultiProcUI.
Steven Kelly,