Swing布局管理器介绍

1、内容面板代码：public static void addComponentsToPane(Container pane) pane.setLayout(new FlowLayout();pane.add(new JButton("Button 1");pane.add(new JButton("Button 2");pane.add(new JButton("Button 3");pane.add(new JButton("Long-Named Button 4");pane.add(new JButton(&q

2、uot;5");BorderLayout一个BorderLayout对象将界面分成五大区域，分别用BorderLayout类的静态常量指定： -PAGE_START-PAGE_END-LINE_START-LINE_END-CENTER效果：内容面板代码：public static void addComponentsToPane(Container pane) JButton button = new JButton("Button 1 (PAGE_START)"); pane.add(button, BorderLayout.PAGE_START);butto

3、n = new JButton("Button 2 (CENTER)");button.setPreferredSize(new Dimension(200, 100);pane.add(button, BorderLayout.CENTER);button = new JButton("Button 3 (LINE_START)");pane.add(button, BorderLayout.LINE_START);button = new JButton("Long-Named Button 4 (PAGE_END)"); pan

4、e.add(button, BorderLayout.PAGE_END);button = new JButton("5 (LINE_END)");pane.add(button, BorderLayout.LINE_END);BoxLayoutBoxLayout可以将组件由上至下或由左至右依次加入当前面板。效果：内容面板代码：public static void addComponentsToPane(Container pane) JPanel xPanel = new JPanel();xPanel.setLayout(new BoxLayout(xPanel, Bo

5、xLayout.X_AXIS); addButtons(xPanel);JPanel yPanel = new JPanel();yPanel.setLayout(new BoxLayout(yPanel, BoxLayout.Y_AXIS); addButtons(yPanel);pane.add(yPanel, BorderLayout.PAGE_START);pane.add(xPanel, BorderLayout.PAGE_END);private static void addAButton(String text, Container container) JButton but

6、ton = new JButton(text);button.setAlignmentX(Component.CENTER_ALIGNMENT);container.add(button);private static void addButtons(Container container) addAButton("Button 1", container);addAButton("Button 2", container);addAButton("Button 3", container);addAButton("Long

7、-Named Button 4", container);addAButton("5", container);CardLayout卡片布局和其他布局不同，因为它隐藏了一些组件。卡片布局就是一组容器或者组件，它们一次仅仅显是一个，组中的每个容器称为卡片。效果：内容面板代码：public void addComponentToPane(Container pane) final JPanel contentPanel = new JPanel();JPanel controlPanel = new JPanel();final CardLayout cardLayo

8、ut=new CardLayout();pane.setLayout(new BorderLayout();pane.add(contentPanel, BorderLayout.CENTER);pane.add(controlPanel, BorderLayout.PAGE_END);controlPanel.setLayout(new FlowLayout();JButton b = new JButton10;for (int i = 0; i < 10; i+) bi = new JButton("No." + i);contentPanel.add(bi);

9、contentPanel.setLayout(cardLayout);JButton nextButton = new JButton("next");nextButton.addActionListener(new ActionListener()public void actionPerformed(ActionEvent e) cardLayout.next(contentPanel););controlPanel.add(nextButton);GridLayoutGridLayout让你建立一个组件表格，并且当组件加入时，会依序又左至右，由上至下填充到每个格子，它

10、不能由你指定想放那个格子就放那个格子效果：内容面板代码：public static void addComponentsToPane(Container pane) JButton buttons = new JButton9;pane.setLayout(new GridLayout(3, 3);for (int i = 0; i < buttons.length; i+) buttonsi = new JButton(i + "");pane.add(buttonsi);GridBagLayoutGridBagLayout是所有AWT布局管理器当中最复杂的，同时他

11、的功能也是最强大的。GridBagLayout同GridLayout一样，在容器中以网格形式来管理组件。但GridBagLayout功能要来得强大得多。1、GridBagLayout管理的所有行和列都可以是大小不同的；2、GridLayout把每个组件限制到一个单元格，而GridBagLayout并不这样：组件在容器中可以占据任意大小的矩形区域。GridBagLayout通常由一个专用类来对他布局行为进行约束，该类叫GridBagConstraints。其中有11个公有成员变量，GridBagConstraints可以从这11个方面来进行控制和操纵。这些内容是：1、gridx组件的横向坐标；2

12、、girdy组件的纵向坐标；3、gridwidth组件的横向宽度，也就是指组件占用的列数；4、gridheight组件的纵向长度，也就是指组件占用的行数；5、weightx指行的权重，告诉布局管理器如何分配额外的水平空间；6、weighty指列的权重，告诉布局管理器如何分配额外的垂直空间；7、anchor当组件小于其显示区域时使用此字段；8、fill如果显示区域比组件的区域大的时候，可以用来控制组件的行为。控制组件是垂直填充，还是水平填充，或者两个方向一起填充；9、insets指组件与表格空间四周边缘的空白区域的大小；10、ipadx 组件间的横向间距，组件的宽度就是这个组件的最小宽度加上ip

13、adx值；11、ipady 组件间的纵向间距，组件的高度就是这个组件的最小高度加上ipady值。说明：1、gridx，gridy：其实就是组件行列的设置，注意都是从0开始的，比如 gridx=0，gridy=1时放在0行1列；2、gridwidth，gridheight：默认值为1；GridBagConstraints.REMAINDER常量，代表此组件为此行或此列的最后一个组件，会占据所有剩余的空间；3、weightx，weighty：当窗口变大时，设置各组件跟着变大的比例。比如组件A的weightx=0.5，组件B的weightx=1，那么窗口X轴变大时剩余的空间就会以1：2的比例分配给组

14、件A和B；4、anchor：当组件空间大于组件本身时，要将组件置于何处。 有CENTER（默认值）、NORTH、NORTHEAST、EAST、SOUTHEAST、WEST、NORTHWEST选择。5、insets：设置组件之间彼此的间距。它有四个参数，分别是上，左，下，右，默认为（0，0，0，0）。效果：内容面板代码：public static void addComponentsToPane(Container pane) JButton button;pane.setLayout(new GridBagLayout();GridBagConstraints c = new GridBagC

15、onstraints();button = new JButton("Button 1");c.fill = GridBagConstraints.HORIZONTAL;c.gridx = 0;c.gridy = 0;pane.add(button, c);button = new JButton("Button 2");c.fill = GridBagConstraints.HORIZONTAL;c.weightx = 0.5;c.gridx = 1;c.gridy = 0;pane.add(button, c);button = new JButto

16、n("Button 3");c.fill = GridBagConstraints.HORIZONTAL;c.weightx = 0.5;c.gridx = 2;c.gridy = 0;pane.add(button, c);button = new JButton("Long-Named Button 4"); c.fill = GridBagConstraints.HORIZONTAL;c.ipady = 40; / make this component tallc.weightx = 0.0;c.gridwidth = 3;c.gridx = 0

17、;c.gridy = 1;pane.add(button, c);button = new JButton("5");c.fill = GridBagConstraints.HORIZONTAL;c.ipady = 0; / reset to defaultc.weighty = 1.0; / request any extra vertical spacec.anchor = GridBagConstraints.PAGE_END; / bottom of space c.insets = new Insets(10, 0, 0, 0); / top paddingc.g

18、ridx = 1; / aligned with button 2c.gridwidth = 2; / 2 columns widec.gridy = 2; / third rowpane.add(button, c);一个GardBagLayout布局的左右选择框，代码GridBagLayoutFrame.java见附件，效果：GridBagLayoutFrame.java附件源码import java.awt.Dimension;import java.awt.GridBagConstraints;import java.awt.GridBagLayout;import java.awt.

19、event.ActionEvent;import java.awt.event.ActionListener;import javax.swing.BorderFactory;import javax.swing.DefaultListModel;import javax.swing.JButton;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JList;import javax.swing.JPanel;import javax.swing.JTextField;public class Gri

20、dBagLayoutFrame extends JFrame private static final long serialVersionUID = 6819222900970457455L; private JPanel mainPanel = new JPanel();private JButton addButton = new JButton();private JButton leftButton = new JButton();private JButton rightButton = new JButton();private JLabel label = new JLabel

21、();private JTextField field = new JTextField();private DefaultListModel leftModel = new DefaultListModel(); private DefaultListModel rightMOdel = new DefaultListModel(); private JList leftList = new JList(leftModel);private JList rightList = new JList(rightMOdel);public GridBagLayoutFrame(String tit

22、le) setTitle("GridBagLayoutFrameDemo");setPreferredSize(new Dimension(600, 400); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); initComponent();addData();pack();setVisible(true);private static void createAndShowGUI() new GridBagLayoutFrame("GridBagLayoutFrameDemo");private void

23、initComponent() label.setText("添加选项：");addButton.setText("添加");leftList.setPreferredSize(new Dimension(150, 150);rightList.setPreferredSize(leftList.getPreferredSize(); leftButton.setText("左");rightButton.setText("右");mainPanel.setBorder(BorderFactory.createTi

24、tledBorder("左右选择框"); mainPanel.setLayout(new GridBagLayout(); GridBagConstraints c = new GridBagConstraints(); c.gridx = 0; / 0行0列 c.gridy = 0; c.gridwidth = 1; c.gridheight = 1; c.fill = GridBagConstraints.HORIZONTAL; c.weightx = 0; c.weighty = 0; mainPanel.add(label, c); c.gridx+; c.weig

25、htx = 1; mainPanel.add(field, c); c.gridx+; c.weightx = 0; c.gridwidth = 1; c.gridheight = 1; / c.fill = GridBagConstraints.HORIZONTAL; mainPanel.add(addButton, c); c.gridx = 0; c.gridy = 1; c.weightx = 1; c.weighty = 1; c.gridwidth = 2; c.gridheight = 2; c.fill = GridBagConstraints.BOTH; mainPanel.

26、add(leftList, c); c.gridx = 2; c.gridy = 1; c.gridwidth = 1; c.gridheight = 1; c.weightx = 0; c.weighty = 0.5; c.anchor = GridBagConstraints.SOUTH; c.fill = GridBagConstraints.HORIZONTAL; mainPanel.add(leftButton, c);c.gridx = 2; c.gridy = 2; c.anchor = GridBagConstraints.NORTH; c.fill = GridBagCons

27、traints.HORIZONTAL; mainPanel.add(rightButton, c); c.gridx = 3; c.gridy = 1; c.gridwidth = 1; c.gridheight = 2; c.weightx = 1; c.weighty = 1; c.fill = GridBagConstraints.BOTH; mainPanel.add(rightList, c); this.getContentPane().add(mainPanel); private void addData() addButton.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) addItem(); ); leftButton.addActionListener(new ActionListener() public void actionPerformed(ActionEvent e) leftItem(); );