| java.lang.Object
 jimm.datavision.gui.cmd.CommandHistory
| CommandHistory | | public class CommandHistory (Code) | | A command history holds comands and manages undo and redo behavior. To
use a new command for the first time, pass it to perform.
You can then call undo and redo to walk the
command history chain.
author:
Jim Menard, jimm@io.com |
| baselineIndex | | protected int baselineIndex(Code) | | If the command index is different than the baseline index then something
has changed, and isChanged will return true.
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| commandIndex | | protected int commandIndex(Code) | | |
| CommandHistory | | public CommandHistory()(Code) | | |
| add | | public synchronized void add(Command command)(Code) | | Add a command to the history list without performing it. If the history
cursor is not at the top of the stack, first erase all of the
commands after the cursor.
Parameters:
command - the command to add |
| canRedo | | public boolean canRedo()(Code) | | Answers the question, "Is there anything to redo?"
|
| canUndo | | public boolean canUndo()(Code) | | Answers the question, "Is there anything to undo?"
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| getCommandName | | public String getCommandName(int index)(Code) | | Return the name of the command at index. Returns null
if there is no such command.
|
| getRedoName | | public String getRedoName()(Code) | | Return the name of the command that would be redone were one to call
redo(). Returns null if there is no such command.
|
| getUndoName | | public String getUndoName()(Code) | | Return the name of the command that would be undone were one to call
undo(). Returns null if there is no such command.
|
| isChanged | | public boolean isChanged()(Code) | | Answers the question, "Has anything changed?"
|
| perform | | public synchronized void perform(Command command)(Code) | | Perform a command and add it to the history list. If the history
cursor is not at the top of the stack, first erase all of the
commands after the cursor.
Parameters:
command - the command to perform |
| redo | | public synchronized void redo()(Code) | | Redo the command under the the history cursor.
|
| setBaseline | | public void setBaseline()(Code) | | Resets the baseline index. The method isChanged returns
false only when the baseline index is equal to the
current command index.
|
| undo | | public synchronized void undo()(Code) | | Undo the command at the history cursor.
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| updateMenu | | protected void updateMenu()(Code) | | |
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