当前页面: 开发资料首页 → Java 专题 → Adding Undo and Redo to a Text Component

Adding Undo and Redo to a Text Component

摘要: Adding Undo and Redo to a Text Component

These code examples and other materials are subject to Sun Microsystems, Inc. Legal Terms
Adding Undo and Redo to a Text Component
JTextArea textarea = new JTextArea(); final UndoManager undo = new UndoManager(); Document doc = textarea.getDocument();
//The next two lines should be in one line. doc.addUndoableEditListener( new UndoableEditListener() { The next two lines should be in one line. public void undoableEditHappened( UndoableEditEvent evt) { undo.addEdit(evt.getEdit()); } });
textarea.getActionMap().put("Undo", new AbstractAction("Undo") { public void actionPerformed(ActionEvent evt) { try { if (undo.canUndo()) { undo.undo(); } } catch (CannotUndoException e) { } } }); textarea.getInputMap().put(KeyStroke.getKeyStroke( "control Z"), "Undo");
textarea.getActionMap().put("Redo", new AbstractAction("Redo") { public void actionPerformed(ActionEvent evt) { try { if (undo.canRedo()) { undo.redo(); } } catch (CannotRedoException e) { } } }); textarea.getInputMap().put(KeyStroke.getKeyStroke( "control Y"), "Redo");
Examplets TM provided by permission of the publisher, Addision-Wesley, and Author Patrick Chan. Order this book from Amazon
↑返回目录
前一篇: Anders Hejlsberg论为什么不在c＃引入类似java的checked exceptions
后一篇: Adapter模式在J2SE事件处理中的应用