Browse Prior Art Database

Improved Design for Graying and Enabling of the Paste Action

IP.com Disclosure Number: IPCOM000107317D
Original Publication Date: 1992-Feb-01
Included in the Prior Art Database: 2005-Mar-21
Document File: 2 page(s) / 86K

Publishing Venue

IBM

Related People

Fleming, SS: AUTHOR

Abstract

This invention eliminates the user interface performance and modality problems associated with conventional approaches for graying and enabling of the paste action.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Improved Design for Graying and Enabling of the Paste Action

       This invention eliminates the user interface performance
and modality problems associated with conventional approaches for
graying and enabling of the paste action.

      In the conventional user interface for the clipboard, the paste
action is grayed when the clipboard is empty. This occurs when the
user's system is first initialized until the user cuts or copies data
to the clipboard.  The clipboard may also become empty as a result of
the user explicitly emptying it, as can be done in some systems
today.

      Thus, the clipboard may change to and from the empty state as a
result of user actions outside of the application supporting the
paste action.  Because of this, conventional applications poll the
clipboard empty status whenever the pull-down containing the paste
action is about to be displayed.  The application must then
appropriately gray or enable the paste action before displaying the
pull-down.

      The polling of the clipboard status and graying or enabling of
the paste action cause a user performance penalty which results in a
noticeably slower display of the pull-down.  This performance penalty
is especially noticeable in lower performance workstations, systems
doing background processing, and applications with slow internal
processing of the polling task.

      Current designs also do not allow future support of modeless
menus, such as tear-off menus or modeless context menus.  This is
because, the clipboard empty state is only checked when the menu is
first displayed.  However, the user may use another application or
the clipboard application to change the empty state.  In current
designs, the tear-off menu or modeless context menus will not be
properly updated to reflect the new clipboard empty state.

      In this invention, a new design for graying and enabling the
paste action is used.  This design is described below:
      1.  The application code is extended to properly support the
clipboard viewer chain messages.  These include WM-CHANGECBCHAIN and
WM-DRAWCLIPBOARD.  The application code is also extended to remove
itself from the clipboard chain, if appropriate,...