Class IzOperationHistoryActionHandler

All Implemented Interfaces:
IAdaptable, IAction, ActionFactory.IWorkbenchAction
Direct Known Subclasses:
IzRedoActionHandler, IzUndoActionHandler

public abstract class IzOperationHistoryActionHandler extends Action implements ActionFactory.IWorkbenchAction, IAdaptable
OperationHistoryActionHandler implements common behavior for the undo and redo actions. It supports filtering of undo or redo on a particular undo context. If an undo context is not specified, or there has been no history available for the specified undo context, then the workbench undo context will be used.

OperationHistoryActionHandler assumes a linear undo/redo model. When the handler is run, the operation history is asked to perform the most recent undo/redo for the handler's undo context. The handler can be configured (using #setPruneHistory(true)) to flush the operation undo or redo history for the handler's undo context when there is no valid operation on top of the history. This avoids keeping a stale history of invalid operations. By default, pruning does not occur and it is assumed that clients of the particular undo context are pruning the history when necessary.

This class is virtually a copy of the Eclipse OperationHistoryActionHandler, with the workbench site requirement removed in order to accommodate a shell instead.

Author:
Christopher Mindus
  • Method Details

    • dispose

      public void dispose()
      Dispose of the action, clean up listener.
      Specified by:
      dispose in interface ActionFactory.IWorkbenchAction
    • run

      public final void run()
      The action run method.
      Specified by:
      run in interface IAction
      Overrides:
      run in class Action
    • getAdapter

      public <T> T getAdapter(Class<T> adapter)
      Adapts...
      Specified by:
      getAdapter in interface IAdaptable
    • setContext

      public void setContext(IUndoContext context)
      Set the context shown by the handler. Normally the context is set up when the action handler is created, but the context can also be changed dynamically.
      Parameters:
      context - The context to be used for the undo history.
    • setPruneHistory

      public void setPruneHistory(boolean prune)
      Specify whether the action handler should actively prune the operation history when invalid operations are encountered. The default value is false.
      Parameters:
      prune - true if the history should be pruned by the handler, and false if it should not.
    • update

      public void update()
      Update enabling and labels according to the current status of the operation history.