listtest2.java

awt图形界面的生成

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

public class ListTest2 extends Applet {
	private DoubleList list;
	private Button   printButton = new Button("Print ...");
	private String[] leftStrs = { "1", "2", "3", "4", "5", 
	                              "6", "7", "8", "9", "10"};
	private String[] rightStrs = { "one", "two", "three", "four", 
	                               "five", "six", "seven", 
								   "eight", "nine", "ten"};
	public void init() {
		Panel controlPanel = new Panel();
		controlPanel.add(printButton);

		setLayout(new BorderLayout());
		add(controlPanel, "North");
		add(list = new DoubleList(leftStrs, rightStrs), "Center");

		printButton.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent event) {
				String[] left  = list.getLeftSideItems();
				String[] right = list.getRightSideItems();
				String[] sleft  = list.getLeftSideSelectedItems();
				String[] sright = list.getRightSideSelectedItems();

				System.out.println("Left Side Items:");
				for(int i=0; i < left.length; ++i)
					System.out.println(left[i]);
				System.out.println();

				System.out.println("Right Side Items:");
				for(int i=0; i < right.length; ++i)
					System.out.println(right[i]);
				System.out.println();

				System.out.println("Left Side Selected Items:");
				for(int i=0; i < sleft.length; ++i)
					System.out.println(sleft[i]);
				System.out.println();

				System.out.println("Right Side Selected Items:");
				for(int i=0; i < sright.length; ++i)
					System.out.println(sright[i]);
				System.out.println();
			}
		});
	}
}
class DoubleList extends Panel {
	private List left = new List(), right = new List();
	private Panel controlPanel = new ControlPanel(this);

	public DoubleList(String[] leftStrs, String[] rightStrs) {
		GridBagLayout      gbl = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();

		left.setMultipleMode (true);
		right.setMultipleMode(true);

		setLayout(gbl);

		gbc.fill    = GridBagConstraints.BOTH;
		gbc.weightx = 1.0;
		gbc.weighty = 1.0;
		gbl.setConstraints(left, gbc);

		gbc.fill    = GridBagConstraints.VERTICAL;
		gbc.weightx = 0;
		gbc.weighty = 1.0;
		gbl.setConstraints(controlPanel, gbc);

		gbc.fill    = GridBagConstraints.BOTH;
		gbc.weightx = 1.0;
		gbc.weighty = 1.0;
		gbl.setConstraints(right, gbc);

		add(left);
		add(controlPanel);
		add(right);

		for(int i=0; i < leftStrs.length; ++i) 
			left.add(leftStrs[i]);

		for(int i=0; i < rightStrs.length; ++i) 
			right.add(rightStrs[i]);
	}
	public void moveLeftToRight() {
		String[] leftSelected = left.getSelectedItems();
		int[]    leftSelectedIndexes = left.getSelectedIndexes();

		for(int i=0; i < leftSelectedIndexes.length; ++i) {
			left.remove(leftSelectedIndexes[i]-i);
		}
		for(int i=0; i < leftSelected.length; ++i) {
			right.add(leftSelected[i], i);
			right.select(i);
		}
	}
	public void moveRightToLeft() {
		String[] rightSelected = right.getSelectedItems();
		int[]    rightSelectedIndexes = right.getSelectedIndexes();

		for(int i=0; i < rightSelectedIndexes.length; ++i) {
			right.remove(rightSelectedIndexes[i]-i);
		}
		for(int i=0; i < rightSelected.length; ++i) {
			left.add(rightSelected[i], i);
			left.select(i);
		}
	}
	public void moveAllRightToLeft() {
		int rightCnt = right.getItemCount();

		for(int i=0; i < rightCnt; ++i) {
			left.add(right.getItem(i), i);
			if(right.isIndexSelected(i))
				left.select(i);
		}
		right.removeAll();
	}
	public void moveAllLeftToRight() {
		int leftCnt = left.getItemCount();

		for(int i=0; i < leftCnt; ++i) {
			right.add(left.getItem(i), i);
			if(left.isIndexSelected(i))
				right.select(i);
		}
		left.removeAll();
	}
	public String[] getRightSideItems() {
		return right.getItems();
	}
	public String[] getRightSideSelectedItems() {
		return right.getSelectedItems();
	}
	public String[] getLeftSideItems() {
		return left.getItems();
	}
	public String[] getLeftSideSelectedItems() {
		return left.getSelectedItems();
	}
}
class ControlPanel extends Panel {
	private DoubleList  doubleList;
	private Button leftToRight     = new Button(">");
	private Button allLeftToRight  = new Button(">>");
	private Button rightToLeft     = new Button("<");
	private Button allRightToLeft  = new Button("<<");
	private Font   buttonFont      = new Font("TimesRoman",
		                                       Font.BOLD, 14);

	public ControlPanel(DoubleList dblList) {
		this.doubleList = dblList;

		GridBagLayout      gbl = new GridBagLayout();
		GridBagConstraints gbc = new GridBagConstraints();

		setLayout(gbl);

		gbc.gridwidth = GridBagConstraints.REMAINDER;
		gbc.fill      = GridBagConstraints.HORIZONTAL;
		gbl.setConstraints(leftToRight,    gbc);
		gbl.setConstraints(allLeftToRight, gbc);
		gbl.setConstraints(rightToLeft,     gbc);
		gbl.setConstraints(allRightToLeft,  gbc);

		add(leftToRight);
		add(allLeftToRight);
		add(rightToLeft);
		add(allRightToLeft);

		leftToRight.setFont   (buttonFont);
		allLeftToRight.setFont(buttonFont);
		rightToLeft.setFont   (buttonFont);
		allRightToLeft.setFont(buttonFont);

		leftToRight.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent event) {
				doubleList.moveLeftToRight();
			}
		});
		allLeftToRight.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent event) {
				doubleList.moveAllLeftToRight();
			}
		});
		rightToLeft.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent event) {
				doubleList.moveRightToLeft();
			}
		});
		allRightToLeft.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent event) {
				doubleList.moveAllRightToLeft();
			}
		});
	}	
	public Insets getInsets() {
		return new Insets(4,4,4,4);
	}
	public void paint(Graphics g) {
		Dimension size = getSize();
		g.setColor(Color.black);
		g.drawRect(0,0,size.width-1,size.height-1);	
		g.setColor(Color.lightGray);
		g.fill3DRect(1,1,size.width-2,size.height-2,true);	
	}
}