spinner.java

ALGAE是一个快速创建算法演示的框架。目前支持的算法实现语言包括java和c

package edu.odu.cs.zeil.AlgAE.gui;

import java.awt.Button;
import java.awt.Checkbox;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Label;
import java.awt.Panel;
import java.awt.TextField;

import java.awt.event.*;

import java.util.Vector;


import java.lang.String;

import edu.odu.cs.zeil.AlgAE.gui.OutlinedPanel;

public class Spinner extends OutlinedPanel
{
  private TextField valueText;
  private int value;
  private int oldValue;
  private int minValue;
  private int maxValue;
  private Vector listeners;


  private void sanityCheck()
  {
    value = Math.min(maxValue, Math.max(minValue, value));
  }
  
  
  public Spinner (int initialValue, int minvalue, int maxvalue)
  {
    listeners = new Vector();
    
    minValue = minvalue;
    maxValue = maxvalue;
    
    oldValue = initialValue;
    value = initialValue;
    sanityCheck();

    Button increaseValueButton = new Button("+");
    Button decreaseValueButton = new Button("-");
    valueText = new TextField(String.valueOf(value), 2);

    setLayout (new FlowLayout());
    add (increaseValueButton);
    add (valueText);
    add (decreaseValueButton);

    increaseValueButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
	++value;
	sanityCheck();
	valueText.setText (String.valueOf(value));
      }});

    decreaseValueButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
	--value;
	sanityCheck();
	valueText.setText (String.valueOf(value));
      }});
    
    valueText.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
	String text = valueText.getText();
	try {
	  value = Integer.valueOf(text).intValue();
	}
	catch (NumberFormatException except) {
	  value = oldValue;
	}
	sanityCheck();
      }});

    addMouseListener(new MouseAdapter() {
      public void mouseExited(MouseEvent e) {
	if (value != oldValue)
	  {
	    oldValue = value;
	    for (int i = 0; i < listeners.size(); ++i)
	      {
		ActionListener a = (ActionListener)listeners.elementAt(i);
		a.actionPerformed
		  (new ActionEvent(Spinner.this,
				   ActionEvent.ACTION_PERFORMED,
				   "spinner value changed"));
	      }
	  }
      }
    });
  }


  /**
     * Get the value of value.
     * @return Value of value.
     */
  public int getValue() {return value;}
  
  /**
     * Set the value of value.
     * @param v  Value to assign to value.
     */
  public void setValue(int  v) {value = v;}

  
  public void addActionListener (ActionListener l)
    {
      listeners.addElement (l);
    }
  
  
}