source: trunk/doc/src/examples/undoframework.qdoc@ 846

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/*!
    \example tools/undoframework 
    \title Undo Framework Example

    This example shows how to implement undo/redo functionality 
    with the Qt undo framework.

    \image undoframeworkexample.png The Undo Diagram Example

    In the Qt undo framework, all actions that the user performs are
    implemented in classes that inherit QUndoCommand. An undo command
    class knows how to both \l{QUndoCommand::}{redo()} - or just do
    the first time - and \l{QUndoCommand::}{undo()} an action. For
    each action the user performs, a command is placed on a
    QUndoStack.  Since the stack contains all commands executed
    (stacked in chronological order) on the document, it can roll the
    state of the document backwards and forwards by undoing and redoing