Asynchronous multi-level undo support in javascript grid

Abstract

Architecture for multi-level undo on a client in grid-based applications. The architecture is a control driven cascading changes system where change tracking works seamlessly in asynchronous (and synchronous) scenarios. A client application is associated with a grid object and, instantiates and configures the grid object. The application can initiate a change to data in the grid and/or the user can edit the data in the grid directly. A result of the change is a notification to the application, the notification including an order key. The application consumes the notification and can then append new changes based on synchronous or asynchronous computations by calling an update function using the order key. The application uses the key to attach further updates which are properly collected together for undo/redo.

What is claimed is: 
     
         1 . A computer-implemented undo system, comprising:
 a change component for tracking asynchronous changes to data via a web application; and   a reverse component for performing reverse operations on the data changes to previous states.   
     
     
         2 . The system of  claim 1 , wherein the data changes are associated with a webpage. 
     
     
         3 . The system of  claim 1 , wherein the web application is a browser application. 
     
     
         4 . The system of  claim 1 , wherein the data changes are made via a client-based data grid. 
     
     
         5 . The system of  claim 4 , wherein the data changes are made manually or programmatically via the grid. 
     
     
         6 . The system of  claim 1 , wherein the reverse operations restore the data to a state that existed according to at least two previous changes. 
     
     
         7 . The system of  claim 1 , wherein the web application receives a notification of a change, the notification including an order key that documents the change relative to other changes. 
     
     
         8 . The system of  claim 1 , wherein the changes are associated with a server document, input to a client-based undo stack for the reverse operations, and tracked in a client-based change tracker. 
     
     
         9 . A computer-implemented method of providing reverse operations in data, comprising:
 detecting data changes in a server document of a server via a client-based grid;   assigning order keys to the changes in a change notification;   sending the change notifications to the server for validation;   receiving asynchronous validation information from the server based on the notifications;   ordering the validation information in the grid according to the order keys; and   managing undo/redo operations in the server document based on the order keys.   
     
     
         10 . The method of  claim 9 , further comprising cascading changes through an undo stack and a change tracker based on the changes in the grid. 
     
     
         11 . The method of  claim 9 , further comprising storing changes in an undo stack and reverting the changes until a first explicit change is reached as part of an undo/redo operation. 
     
     
         12 . The method of  claim 9 , further comprising storing explicit changes in a change tracker data structure. 
     
     
         13 . The method of  claim 9 , further comprising reverting all implicit changes before a next explicit action and then reverting the next explicit action. 
     
     
         14 . A computer-implemented method of providing reverse operations in data, comprising:
 initiating data changes to a web document of a server via a client web application;   storing the changes as an ordered history of the changes in a client undo stack and change entries in a client change tracker;   validating the changes at the server;   receiving validation information asynchronously from the server into the web application; and   managing undo/redo operations in the web document based on the ordered history of the changes in the undo stack and the change entries in the change tracker.   
     
     
         15 . The method of  claim 14 , further comprising exposing the data changes and visualization of the data changes via a client data grid. 
     
     
         16 . The method of  claim 14 , further comprising undoing changes in the web document that have occurred before a save operation performed in the web application. 
     
     
         17 . The method of  claim 14 , further comprising, in response to a save operation, reading changes from the change tracker, committing the changes to a datasource, and clearing the change tracker. 
     
     
         18 . The method of  claim 14 , wherein the ordered history of the changes is based on a change key assigned to each change. 
     
     
         19 . The method of  claim 14 , further comprising storing implicit change information and explicit change information in the undo stack along with functions to execute to undo implicit and explicit changes. 
     
     
         20 . The method of  claim 14 , further comprising exporting explicating changes as a collection of cell-level changes.