疯狂JAVA讲义---第十二章：Swing编程（六）微调控制器和列表框

今天主要讲下JSpinner和JList。JSpinner用的不多，一般都用滚动条来代替，但当值要精确时，用滚动条会经常滚不到自己要的值，这也是很尴尬的，这时JSpinner就派上用场了。

其实JSpinner没什么花样，主要构造时要传个SpinnerModel，这个类有3个子类

SpinnerNumberModel用于设置数值型的JSpinner

SpinnerDateModel用于实现时间控件的微调

SpinnerListModel用于传入List或数组之间的微调，eg

public class TestJSpinner{final int SPINNER_NUM = 6;JFrame mainWin = new JFrame("微调控制器示范");Box spinnerBox = new Box(BoxLayout.Y_AXIS);JSpinner[] spinners = new JSpinner[SPINNER_NUM];JLabel[] valLabels = new JLabel[SPINNER_NUM];JButton okBn = new JButton("确定");public void init() {for (int i = 0 ; i < SPINNER_NUM ; i++ ){valLabels[i] = new JLabel();}//-----------普通Spinner-----------spinners[0] = new JSpinner();addSpinner(spinners[0], "普通" , valLabels[0]);//-----------指定最小值、最大值、步长的Spinner-----------//创建一个SpinnerNumberModel对象，指定最小值、最大值和步长SpinnerNumberModel numModel = new SpinnerNumberModel(3.4, -1.1, 4.3, 0.1); spinners[1] = new JSpinner(numModel);addSpinner(spinners[1], "数 值 范 围" , valLabels[1]);//-----------使用SpinnerListModel的Spinner------------String[] books = new String[]{"轻量级J2EE企业应用实战","Struts2权威指南","基于J2EE的Ajax宝典"};//使用字符串数组创建SpinnerListModel对象SpinnerListModel bookModel = new SpinnerListModel(books);//使用SpinnerListModel对象创建JSpinner对象spinners[2] = new JSpinner(bookModel);addSpinner(spinners[2], "字符串序列值" , valLabels[2]);//-----------使用序列值是ImageIcon的Spinner------------ArrayList<ImageIcon> icons = new ArrayList<ImageIcon>();icons.add(new ImageIcon("a.gif"));icons.add(new ImageIcon("b.gif"));//使用ImageIcon数组创建SpinnerListModel对象SpinnerListModel iconModel = new SpinnerListModel(icons);//使用SpinnerListModel对象创建JSpinner对象spinners[3] = new JSpinner(iconModel);addSpinner(spinners[3], "图标序列值" , valLabels[3]);//-----------使用SpinnerDateModel的Spinner------------//分别获取起始时间、结束时间、初时时间Calendar cal = Calendar.getInstance();Date init = cal.getTime();cal.add(Calendar.DAY_OF_MONTH , -3);Date start = cal.getTime();cal.add(Calendar.DAY_OF_MONTH , 8);Date end = cal.getTime();//创建一个SpinnerDateModel对象，指定最小时间、最大时间和初始时间SpinnerDateModel dateModel = new SpinnerDateModel(init , start , end , Calendar.HOUR_OF_DAY);//以SpinnerDateModel对象创建JSpinnerspinners[4] = new JSpinner(dateModel);addSpinner(spinners[4], "时 间 范 围" , valLabels[4]);//-----------使用DateEditor来格式化Spinner------------dateModel = new SpinnerDateModel();spinners[5] = new JSpinner(dateModel);//创建一个JSpinner.DateEditor对象，用于对指定Spinner进行格式化JSpinner.DateEditor editor = new JSpinner.DateEditor(spinners[5],"公元yyyy年MM月dd日 HH时");//设置使用JSpinner.DateEditor对象进行格式化spinners[5].setEditor(editor);addSpinner(spinners[5], "使用DateEditor" , valLabels[5]);//为“确定”按钮添加一个事件监听器okBn.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent evt){//取出每个微调控制器的值，并将该值用后面的Label标签显示出来。for (int i = 0 ; i < SPINNER_NUM ; i++){valLabels[i].setText(spinners[i].getValue().toString());}}});JPanel bnPanel = new JPanel();bnPanel.add(okBn);mainWin.add(spinnerBox, BorderLayout.CENTER);mainWin.add(bnPanel, BorderLayout.SOUTH);mainWin.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);mainWin.pack();mainWin.setVisible(true);}//定义一个方法，用于将滑动条添加到容器中public void addSpinner(JSpinner spinner, String description,JLabel valLabel){Box box = new Box(BoxLayout.X_AXIS);JLabel desc = new JLabel(description + "：");desc.setPreferredSize(new Dimension(100 , 30));box.add(desc);box.add(spinner);valLabel.setPreferredSize(new Dimension(180 , 30));box.add(valLabel);spinnerBox.add(box);}public static void main(String[] args){new TestJSpinner().init();}}

相比前面的Jspinner来说，JList和JComboBox就用的多些，eg

public class TestList{private JFrame mainWin = new JFrame("测试列表框");String[] books = new String[]{"Spring2.0宝典","轻量级J2EE企业应用实战","基于J2EE的Ajax宝典","Struts2权威指南","ROR敏捷开发最佳实践"};JList bookList = new JList(books);JComboBox bookSelector;//定义布局选择按钮所在的面板JPanel layoutPanel = new JPanel();ButtonGroup layoutGroup = new ButtonGroup();//定义选择模式按钮所在的面板JPanel selectModePanel = new JPanel();ButtonGroup selectModeGroup = new ButtonGroup();JTextArea favoriate = new JTextArea(4 , 40);public void init(){//JList的可视高度可同时显示三个列表项bookList.setVisibleRowCount(3); //默认选中第三项到第五项（第一项的索引是0）bookList.setSelectionInterval(2, 4);addLayoutButton("纵向滚动", JList.VERTICAL);addLayoutButton("纵向换行", JList.VERTICAL_WRAP);addLayoutButton("横向换行", JList.HORIZONTAL_WRAP);addSelectModelButton("无限制", ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);addSelectModelButton("单选", ListSelectionModel.SINGLE_SELECTION);addSelectModelButton("单范围", ListSelectionModel.SINGLE_INTERVAL_SELECTION);Box listBox = new Box(BoxLayout.Y_AXIS);//将JList组件放在JScrollPane中，再将该JScrollPane添加到listBox容器中listBox.add(new JScrollPane(bookList));//添加布局选择按钮面板、选择模式按钮面板listBox.add(layoutPanel);listBox.add(selectModePanel);//为JList添加事件监听器bookList.addListSelectionListener(new ListSelectionListener(){public void valueChanged(ListSelectionEvent e){//获取用户所选择的所有图书Object[] books = bookList.getSelectedValues();favoriate.setText("");for (Object book : books ){favoriate.append(book.toString() + "/n");}}});Vector<String> bookCollection = new Vector<String>();bookCollection.add("Spring2.0宝典");bookCollection.add("轻量级J2EE企业应用实战");bookCollection.add("基于J2EE的Ajax宝典");bookCollection.add("Struts2权威指南");bookCollection.add("ROR敏捷开发最佳实践");//用一个Vector对象来创建一个JComboBox对象bookSelector = new JComboBox(bookCollection);//为JComboBox添加事件监听器bookSelector.addItemListener(new ItemListener(){public void itemStateChanged(ItemEvent e) {//获取JComboBox所选中的项Object book = bookSelector.getSelectedItem();favoriate.setText(book.toString());}});//设置可以直接编辑bookSelector.setEditable(true);//设置下拉列表框的可视高度可同时显示4个列表项bookSelector.setMaximumRowCount(4);JPanel p = new JPanel();p.add(bookSelector);Box box = new Box(BoxLayout.X_AXIS);box.add(listBox);box.add(p);mainWin.add(box);JPanel favoriatePanel = new JPanel();favoriatePanel.setLayout(new BorderLayout());favoriatePanel.add(new JScrollPane(favoriate));favoriatePanel.add(new JLabel("您喜欢的图书：") , BorderLayout.NORTH);mainWin.add(favoriatePanel , BorderLayout.SOUTH);mainWin.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);mainWin.pack();mainWin.setVisible(true);}private void addLayoutButton(String label, final int orientation){layoutPanel.setBorder(new TitledBorder(new EtchedBorder(), "确定选项布局"));JRadioButton button = new JRadioButton(label);//把该单选按钮添加到layoutPanel面板中layoutPanel.add(button);//默认选中第一个按钮if (layoutGroup.getButtonCount() == 0) button.setSelected(true);layoutGroup.add(button);button.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent event){//改变列表框里列表项的布局方向bookList.setLayoutOrientation(orientation);}});}private void addSelectModelButton(String label, final int selectModel){selectModePanel.setBorder(new TitledBorder(new EtchedBorder(), "确定选择模式"));JRadioButton button = new JRadioButton(label);//把该单选按钮添加到selectModePanel面板中selectModePanel.add(button);//默认选中第一个按钮if (selectModeGroup.getButtonCount() == 0) button.setSelected(true);selectModeGroup.add(button);button.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent event){//改变列表框里的选择模式bookList.setSelectionMode(selectModel);}});}public static void main(String[] args) {new TestList().init();}}

JList和JComboBox除了样子上的区别，就是JComboBox只支持单选，而JList可以多选。