java的Swing库采用Beans的方式允许我们更加方便的创建界面。
1:进度条
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
public class Progress extends JPanel {
JProgressBar pb = new JProgressBar(); //进度条
JSlider sb = new JSlider(JSlider.HORIZONTAL, 0, 100, 60);//滑动条
public Progress() {
setLayout(new GridLayout(2,1));
add(pb);
sb.setValue(0);
sb.setPaintTicks(true);
sb.setMajorTickSpacing(20); //设置滑动条的主间隔个数
sb.setMinorTickSpacing(5); //每个间隔细分为5个间隔
sb.setBorder(new TitledBorder("Slide Me"));
pb.setModel(sb.getModel()); // Share model
add(sb);
}
public static void main(String args[]) {
JFrame jf = new JFrame();
Progress pro = new Progress();
jf.add(pro);
jf.setSize(200,300);
jf.setVisible(true);
}
} ///:~
结果如下所示:
2:ButtonGroup以及动态映射
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import java.lang.reflect.*;
public class ButtonGroups extends JPanel {
static String[] ids = {
"June", "Ward", "Beaver","Wally", "Eddie", "Lumpy",
};
static JPanel makeBPanel(Class bClass, String[] ids) {
ButtonGroup bg = new ButtonGroup();
JPanel jp = new JPanel();
String title = bClass.getName();
title = title.substring( title.lastIndexOf('.') + 1);
jp.setBorder(new TitledBorder(title));
for(int i = 0; i < ids.length; i++) {
AbstractButton ab = new JButton("failed");
try {
//动态获得一个有一个String参数的构造函数
Constructor ctor = bClass.getConstructor(new Class[] { String.class });
//创造一个Object
ab = (AbstractButton)ctor.newInstance(new Object[]{ids[i]});
} catch(Exception ex) {
System.out.println("can't create " + bClass);
}
bg.add(ab);//按钮组添加按钮
jp.add(ab);
}
return jp;
}
public ButtonGroups() {
add(makeBPanel(JButton.class, ids));
add(makeBPanel(JToggleButton.class, ids));
add(makeBPanel(JCheckBox.class, ids));
add(makeBPanel(JRadioButton.class, ids));
}
public static void main(String args[]) {
JFrame jf = new JFrame();
ButtonGroups btg = new ButtonGroups();
jf.add(btg);
jf.setSize(500,300);
jf.setVisible(true);
}
} ///:~
结果如下所示:
这个程序的特点就是通过reflect来实现添加不同类型的按钮组,AbstractButton 是所有不同类型的button的父类,所以可以通过它来操作子类的重定义函数。通过Constructor ctor = bClass.getConstructor(new Class[] { String.class });来获得有一个参数是String类型的构造函数,通过ab = (AbstractButton)ctor.newInstance(new Object[]{ids[i]});来创建一个button的对象。
ButtonGroup的作用就是一个button组中有一个被选中其他button就处于落选状态。
3:按钮图标
static Icon face = new Icon("face0.jpg");//建立图标
JButton jb = new JButton("bt",face); //建立带有图标的按钮
jb.setIcon(face);//设置图标
jb.setRolloverIcon(faces[1]);//设置滚动时的按钮图标
jb.setPressedIcon(faces[2]); //设置按下时的按钮图标
jb.setDisabledIcon(faces[4]);//设置禁用时的按钮图标
结果如下所示:
4:弹出菜单
弹出菜单也很简单,包括菜单的创建,菜单命令的响应,如下所示:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Popup extends JPanel {
JPopupMenu popup = new JPopupMenu();
JTextField t = new JTextField(10);
public Popup() {
add(t);
ActionListener al = new ActionListener() {
public void actionPerformed(ActionEvent e){
t.setText( ((JMenuItem)e.getSource()).getText());
}
};
JMenuItem m = new JMenuItem("Hither");
m.addActionListener(al);
popup.add(m);
m = new JMenuItem("Yon");
m.addActionListener(al);
popup.add(m);
m = new JMenuItem("Afar");
m.addActionListener(al);
popup.add(m);
popup.addSeparator();
m = new JMenuItem("Stay Here");
m.addActionListener(al);
popup.add(m);
PopupListener pl= new PopupListener();
addMouseListener(pl);
t.addMouseListener(pl);//这样即便鼠标点击label,也会弹出菜单
}
class PopupListener extends MouseAdapter {
public void mousePressed(MouseEvent e) {
maybeShowPopup(e);
}
public void mouseReleased(MouseEvent e) {
maybeShowPopup(e);
}
private void maybeShowPopup(MouseEvent e) {
//判断鼠标事件是否为弹出菜单的触发事件
if(e.isPopupTrigger()) {
popup.show(e.getComponent(), e.getX(), e.getY());
}
}
}
public static void main(String args[]) {
JFrame jf = new JFrame();
Popup pm = new Popup();
jf.add(pm);
jf.setSize(500,500);
jf.setVisible(true);
}
} ///:~
结果如下所示:
通过鼠标监听器来监听弹出菜单事件,e.isPopupTrigger()来判断是否是弹出菜单的触发事件;popup.show(e.getComponent(), e.getX(), e.getY());在点击鼠标的位置显示弹出菜单;
5:树形控件
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.tree.*;
// Takes an array of Strings and makes the first
// element a node and the rest leaves:
class Branch {
DefaultMutableTreeNode r;
public Branch(String[] data) {
r = new DefaultMutableTreeNode(data[0]);
for(int i = 1; i < data.length; i++)
r.add(new DefaultMutableTreeNode(data[i]));
}
public DefaultMutableTreeNode node() {
return r;
}
}
public class Trees extends JPanel {
String[][] data = {
{ "Colors", "Red", "Blue", "Green" },
{ "Flavors", "Tart", "Sweet", "Bland" },
{ "Length", "Short", "Medium", "Long" },
{ "Volume", "High", "Medium", "Low" },
{ "Temperature", "High", "Medium", "Low" },
{ "Intensity", "High", "Medium", "Low" },
};
static int i = 0;
DefaultMutableTreeNode root, child, chosen;
JTree tree;
DefaultTreeModel model;
public Trees() {
setLayout(new BorderLayout());
root = new DefaultMutableTreeNode("root");//建立树的根节点
tree = new JTree(root);//建立一棵树
// Add it and make it take care of scrolling:
add(new JScrollPane(tree), BorderLayout.CENTER);
// Capture the tree's model:
model =(DefaultTreeModel)tree.getModel();
JButton test = new JButton("Press me");
test.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e){
if(i < data.length)
{
//通过Branch建立子节点的所有节点
child = new Branch(data[i++]).node();
// What's the last one you clicked?
chosen = (DefaultMutableTreeNode)tree.getLastSelectedPathComponent();
if(chosen == null)
chosen = root;
// The model will create the appropriate event. In
// response, the tree will update itself:
model.insertNodeInto(child, chosen, 0);
// This puts the new node on the currently chosen node.
}
}
});
// Change the button's colors:
test.setBackground(Color.blue);
test.setForeground(Color.white);
JPanel p = new JPanel();
p.add(test);
add(p, BorderLayout.SOUTH);
}
public static void main(String args[]) {
JFrame jf = new JFrame();
Trees nt = new Trees();
jf.add(nt);
jf.setSize(1000,1000);
jf.setVisible(true);
}
} ///:~
结果如下所示:
程序中通过Branch来建立一个分支,这个分支是两层的,包含一个根节点以及几个叶子节点;
通过按钮PressMe来负责树形控件中节点的插入,
chosen = (DefaultMutableTreeNode)tree.getLastSelectedPathComponent();这句话获取最后选择的节点,插入会在此节点下插入;
model.insertNodeInto(child, chosen, 0);这句话表示插入分支child,插入位置是chosen,0表示插在它下面的第一个位置
6:表格的创建
java中表格的创建还是比较方便的,我们只需要实现interface TableModel中的三个主要的函数即可,所以我们要用到抽象类
AbstracttableModel,这个类实现了tableModel 中的大部分函数,但是三个函数
public int getRowCount();
public int getColumnCount();
public Object getValueAt(int row, int column);
需要我们另外独自去实现。下面的程序很好的说明了这一点:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;
import javax.swing.event.*;
// T he TableModel controls all the data:
class DataModel extends AbstractTableModel {
Object[][] data = {
{"one", "two", "three", "four"},
{"five", "six", "seven", "eight"},
{"nine", "ten", "eleven", "twelve"},
};
// Prints data when table changes:
class TML implements TableModelListener {
public void tableChanged(TableModelEvent e) {
for(int i = 0; i < data.length; i++) {
for(int j = 0; j < data[0].length; j++)
System.out.print(data[i][j] + " ");
System.out.println();
}
}
}
DataModel() {
addTableModelListener(new TML());
}
//必须完成interface TableModel的函数
public int getColumnCount() {
return data[0].length;
}
//必须完成interface TableModel的函数
public int getRowCount() {
return data.length;
}
//必须完成interface TableModel的函数
public Object getValueAt(int row, int col) {
return data[row][col];
}
public void setValueAt(Object val, int row, int col) {
data[row][col] = val;
// Indicate the change has happened:
fireTableDataChanged();
}
public boolean isCellEditable(int row, int col) {
return true;
}
};
public class Table extends JPanel {
public Table() {
setLayout(new BorderLayout());
JTable table = new JTable(new DataModel());
JScrollPane scrollpane = JTable.createScrollPaneForTable(table);
add(scrollpane, BorderLayout.CENTER);
}
public static void main(String args[]) {
JFrame jf = new JFrame();
Table ta = new Table();
jf.add(ta);
jf.setSize(300,300);
jf.setVisible(true);
}
}
结果如下所示: