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谁给看看？？？
来源: 互联网 发布时间：2017-04-17
本文导语: import java.awt.*; import java.awt.event.*; import javax.swing.*; import javax.swing.text.*; import javax.swing.undo.*; import javax.swing.event.*; public class UndoTest extends JFrame { protected Container pane; protected UndoAction un...
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.undo.*;
import javax.swing.event.*;
public class UndoTest extends JFrame {
protected Container pane;
protected UndoAction undoAction=new UndoAction();
protected RedoAction redoAction=new RedoAction();
protected UndoManager undoManager=new UndoManager();
public static void main(String args[]) {
UndoTest ut=new UndoTest();
ut.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ut.setSize(400,300);
ut.setVisible(true);
}
public void UndoTest() {
BuildLayout();
}
public void BuildLayout() {
pane=getContentPane();
JMenuBar jmb=new JMenuBar();
setJMenuBar(jmb);
JMenu jm=new JMenu("Edit");
jmb.add(jm);
jm.add(new JMenuItem("Test"));
jm.add(undoAction);
jm.add(redoAction);
JTextField textfield=new JTextField(10);
createUndoListener(textfield.getDocument());
pane.setLayout(new BorderLayout());
pane.add(textfield,BorderLayout.SOUTH);
undoAction.refreshUndoState();
redoAction.refreshRedoState();
}
protected void createUndoListener(Document document) {
document.addUndoableEditListener(new UndoableEditListener() {
public void undoableEditHappened(UndoableEditEvent uee){
undoManager.addEdit(uee.getEdit());
undoAction.refreshUndoState();
redoAction.refreshRedoState();
}
});
}
class UndoAction extends AbstractAction {
public UndoAction() {
super("Undo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.undo();
} catch (CannotUndoException cue) {
JOptionPane.showMessageDialog(pane,"Unable to Undo:"+cue);
}
refreshUndoState();
redoAction.refreshRedoState();
}
protected void refreshUndoState() {
if (undoManager.canUndo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getUndoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Undo");
}
}
}
class RedoAction extends AbstractAction {
public RedoAction() {
super("Redo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.redo();
} catch(CannotRedoException cre) {
JOptionPane.showMessageDialog(pane,"Unable to redo:"+cre);
}
refreshRedoState();
undoAction.refreshUndoState();
}
protected void refreshRedoState() {
if (undoManager.canRedo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getRedoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Redo");
}
}
}
}
这个程序是书上抄的，编译可以通过，可是却看不到程序中要显示的内容，谁给看看
。
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.undo.*;
import javax.swing.event.*;
public class UndoTest extends JFrame {
protected Container pane;
protected UndoAction undoAction=new UndoAction();
protected RedoAction redoAction=new RedoAction();
protected UndoManager undoManager=new UndoManager();
public static void main(String args[]) {
UndoTest ut=new UndoTest();
ut.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ut.setSize(400,300);
ut.setVisible(true);
}
public void UndoTest() {
BuildLayout();
}
public void BuildLayout() {
pane=getContentPane();
JMenuBar jmb=new JMenuBar();
setJMenuBar(jmb);
JMenu jm=new JMenu("Edit");
jmb.add(jm);
jm.add(new JMenuItem("Test"));
jm.add(undoAction);
jm.add(redoAction);
JTextField textfield=new JTextField(10);
createUndoListener(textfield.getDocument());
pane.setLayout(new BorderLayout());
pane.add(textfield,BorderLayout.SOUTH);
undoAction.refreshUndoState();
redoAction.refreshRedoState();
}
protected void createUndoListener(Document document) {
document.addUndoableEditListener(new UndoableEditListener() {
public void undoableEditHappened(UndoableEditEvent uee){
undoManager.addEdit(uee.getEdit());
undoAction.refreshUndoState();
redoAction.refreshRedoState();
}
});
}
class UndoAction extends AbstractAction {
public UndoAction() {
super("Undo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.undo();
} catch (CannotUndoException cue) {
JOptionPane.showMessageDialog(pane,"Unable to Undo:"+cue);
}
refreshUndoState();
redoAction.refreshRedoState();
}
protected void refreshUndoState() {
if (undoManager.canUndo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getUndoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Undo");
}
}
}
class RedoAction extends AbstractAction {
public RedoAction() {
super("Redo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.redo();
} catch(CannotRedoException cre) {
JOptionPane.showMessageDialog(pane,"Unable to redo:"+cre);
}
refreshRedoState();
undoAction.refreshUndoState();
}
protected void refreshRedoState() {
if (undoManager.canRedo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getRedoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Redo");
}
}
}
}
这个程序是书上抄的，编译可以通过，可是却看不到程序中要显示的内容，谁给看看
。
|
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.undo.*;
import javax.swing.event.*;
public class UndoTest extends JFrame {
protected Container pane;
protected UndoAction undoAction=new UndoAction();
protected RedoAction redoAction=new RedoAction();
protected UndoManager undoManager=new UndoManager();
public static void main(String args[]) {
UndoTest ut=new UndoTest();
// ut.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ut.setSize(400,300);
ut.setVisible(true);
}
public void BuildLayout() {
pane=getContentPane();
JMenuBar jmb=new JMenuBar();
JMenu jm=new JMenu("Edit");
jm.add(new JMenuItem("Test"));
jm.add(new JMenuItem("Test2"));
jm.add(undoAction);
jm.add(redoAction);
jmb.add(jm);
this.setJMenuBar(jmb);
JTextField textfield=new JTextField(10);
createUndoListener(textfield.getDocument());
pane.setLayout(new BorderLayout());
pane.add(textfield,BorderLayout.SOUTH);
undoAction.refreshUndoState();
redoAction.refreshRedoState();
this.validate();
}
protected void createUndoListener(Document document) {
document.addUndoableEditListener(new UndoableEditListener() {
public void undoableEditHappened(UndoableEditEvent uee){
undoManager.addEdit(uee.getEdit());
undoAction.refreshUndoState();
redoAction.refreshRedoState();
}
});
}
class UndoAction extends AbstractAction {
public UndoAction() {
super("Undo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.undo();
} catch (CannotUndoException cue) {
JOptionPane.showMessageDialog(pane,"Unable to Undo:"+cue);
}
refreshUndoState();
redoAction.refreshRedoState();
}
protected void refreshUndoState() {
if (undoManager.canUndo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getUndoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Undo");
}
}
}
class RedoAction extends AbstractAction {
public RedoAction() {
super("Redo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.redo();
} catch(CannotRedoException cre) {
JOptionPane.showMessageDialog(pane,"Unable to redo:"+cre);
}
refreshRedoState();
undoAction.refreshUndoState();
}
protected void refreshRedoState() {
if (undoManager.canRedo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getRedoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Redo");
}
}
}
public UndoTest()
{
BuildLayout();
}
}
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.undo.*;
import javax.swing.event.*;
public class UndoTest extends JFrame {
protected Container pane;
protected UndoAction undoAction=new UndoAction();
protected RedoAction redoAction=new RedoAction();
protected UndoManager undoManager=new UndoManager();
public static void main(String args[]) {
UndoTest ut=new UndoTest();
// ut.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ut.setSize(400,300);
ut.setVisible(true);
}
public void BuildLayout() {
pane=getContentPane();
JMenuBar jmb=new JMenuBar();
JMenu jm=new JMenu("Edit");
jm.add(new JMenuItem("Test"));
jm.add(new JMenuItem("Test2"));
jm.add(undoAction);
jm.add(redoAction);
jmb.add(jm);
this.setJMenuBar(jmb);
JTextField textfield=new JTextField(10);
createUndoListener(textfield.getDocument());
pane.setLayout(new BorderLayout());
pane.add(textfield,BorderLayout.SOUTH);
undoAction.refreshUndoState();
redoAction.refreshRedoState();
this.validate();
}
protected void createUndoListener(Document document) {
document.addUndoableEditListener(new UndoableEditListener() {
public void undoableEditHappened(UndoableEditEvent uee){
undoManager.addEdit(uee.getEdit());
undoAction.refreshUndoState();
redoAction.refreshRedoState();
}
});
}
class UndoAction extends AbstractAction {
public UndoAction() {
super("Undo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.undo();
} catch (CannotUndoException cue) {
JOptionPane.showMessageDialog(pane,"Unable to Undo:"+cue);
}
refreshUndoState();
redoAction.refreshRedoState();
}
protected void refreshUndoState() {
if (undoManager.canUndo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getUndoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Undo");
}
}
}
class RedoAction extends AbstractAction {
public RedoAction() {
super("Redo");
}
public void actionPerformed(ActionEvent event) {
try {
undoManager.redo();
} catch(CannotRedoException cre) {
JOptionPane.showMessageDialog(pane,"Unable to redo:"+cre);
}
refreshRedoState();
undoAction.refreshUndoState();
}
protected void refreshRedoState() {
if (undoManager.canRedo()) {
setEnabled(true);
putValue(Action.NAME,undoManager.getRedoPresentationName());
}
else {
setEnabled(false);
putValue(Action.NAME,"Redo");
}
}
}
public UndoTest()
{
BuildLayout();
}
}
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本站(WWW.)站内文章除注明原创外，均为转载、整理或搜集自网络。欢迎任何形式的转载，转载请注明出处。