calc.java

计算机代数系统

package net.sf.yacas;


import java.lang.*;
import java.awt.*;
import java.applet.*;
import java.awt.event.*;
import java.util.*;
import java.math.*;

public class calc extends Applet implements ActionListener //, Runnable
{
  YacasNotebookComponent notebook;
	 
	Button button1 = new Button("1 (./?)");
	Button button2 = new Button("2 (abc)");
	Button button3 = new Button("3 (def)");
	Button button4 = new Button("4 (ghi)");
	Button button5 = new Button("5 (jkl)");
	Button button6 = new Button("6 (mno)");
	Button button7 = new Button("7 (pqrs)");
	Button button8 = new Button("8 (tuv)");
	Button button9 = new Button("9 (wxyz)");
	Button buttonRoll = new Button("*+");
	Button button0 = new Button("0 [ ]");
	Button buttonEnter = new Button("#");

  // arrows
  Button buttonUp       = new Button("/\\"); 
  Button buttonDown     = new Button("\\/"); 
  Button buttonLeft     = new Button("<"); 
  Button buttonRight    = new Button(">"); 
	Button buttonCenter   = new Button("O");
	Button buttonClear    = new Button("C");

	/* This the only method that is called explicitly -- every other method is 
	 * called depending on the user's actions.
	 */
	public void init() 
	{   
    notebook = new YacasNotebookComponent(getDocumentBase().toString()+".hints",this);

		//Allows for configuring a layout with the restraints of a grid or 
		//something similar
		setLayout(null);
		
		//This will resize the applet to the width and height provided
		resize(276/*420*/,540/*368*/);
		
		//This sets the default font to Helvetica, plain, size 12
		setFont(new Font("Helvetica", Font.PLAIN, 12));

		/* Display Panel, which appears at the top of the screen. The label is
		 * placed and sized with the setBounds(x,y,width,height) method, and the
		 * font, foreground color and background color are all set. Then the 
		 * label is added to the layout of the applet.
		 */
		notebook.setBounds(42,15,192/*308*/,240);
//		notebook.setFont(new Font("Helvetica", Font.PLAIN, 20));
//		notebook.setForeground(new Color(65280));
//		notebook.setBackground(new Color(0));
//		add(notebook);
		
		/* Memory Panel, which appears just to the right of the Display Panel.
		 * The label is placed and sized with the setBounds(x,y,width,height)
		 * method, and the font, foreground color and background color are all
		 * set. Then the label is added to the layout of the applet.
		 */
		/* The following declarations initialize all of the Numberic Buttons
		 * that will displayed on the applet. 
		 * 
		 * First, an ActionListener (which will capture events) is added to the 
		 * button, sending the applet as the argument
		 * 
		 * Second, the button is placed and sized with the setBounds(x,y,width,
		 * height) method.
		 * 
		 * Then the default font is set for the button, and the button is added
		 * to the layout of the applet.
		 */
    Font font = new Font("Dialog", Font.BOLD, 9);

		buttonUp.addActionListener(this);
		buttonUp.setBounds(106,274+38*0,60,34);
		buttonUp.setFont(font);
		buttonUp.setForeground(new Color(0xff));
		add(buttonUp);

		buttonLeft.addActionListener(this);
		buttonLeft.setBounds(42,274+38*1,60,34);
		buttonLeft.setFont(font);
		buttonLeft.setForeground(new Color(0xff));
		add(buttonLeft);

		buttonCenter.addActionListener(this);
		buttonCenter.setBounds(106,274+38*1,60,34);
		buttonCenter.setFont(font);
		add(buttonCenter);

		buttonRight.addActionListener(this);
		buttonRight.setBounds(170,274+38*1,60,34);
		buttonRight.setFont(font);
		buttonRight.setForeground(new Color(0xff));
		add(buttonRight);

		buttonDown.addActionListener(this);
		buttonDown.setBounds(106,274+38*2,60,34);
		buttonDown.setFont(font);
		buttonDown.setForeground(new Color(0xff));
		add(buttonDown);

		buttonClear.addActionListener(this);
		buttonClear.setBounds(170,274+38*2,60,34);
		buttonClear.setFont(font);
		buttonClear.setForeground(new Color(0xff0000));
		add(buttonClear);


		button1.addActionListener(this);
		button1.setBounds(42,274+38*3,60,34);
		button1.setFont(font);
		add(button1);

		button2.addActionListener(this);
		button2.setBounds(106,274+38*3,60,34);
		button2.setFont(font);
		add(button2);

		button3.addActionListener(this);
		button3.setBounds(170,274+38*3,60,34);
		button3.setFont(font);
		add(button3);

		button4.addActionListener(this);
		button4.setBounds(42,274+38*4,60,34);
		button4.setFont(font);
		add(button4);

		button5.addActionListener(this);
		button5.setBounds(106,274+38*4,60,34);
		button5.setFont(font);
		add(button5);

		button6.addActionListener(this);
		button6.setBounds(170,274+38*4,60,34);
		button6.setFont(font);
		add(button6);

		button7.addActionListener(this);
		button7.setBounds(42,274+38*5,60,34);
		button7.setFont(font);
		add(button7);

		button8.addActionListener(this);
		button8.setBounds(106,274+38*5,60,34);
		button8.setFont(font);
		add(button8);

		button9.addActionListener(this);
		button9.setBounds(170,274+38*5,60,34);
		button9.setFont(font);
		add(button9);


		buttonRoll.addActionListener(this);
		buttonRoll.setBounds(42,274+38*6,60,34);
		buttonRoll.setFont(font);
		add(buttonRoll);

		button0.addActionListener(this);
		button0.setBounds(106,274+38*6,60,34);
		button0.setFont(font);
		add(button0);

		buttonEnter.addActionListener(this);
		buttonEnter.setBounds(170,274+38*6,60,34);
		buttonEnter.setFont(font);
		add(buttonEnter);
    invalidate();
  }	//end of calc init method
	

	
  
/***************************************************************************
 * 
 * This is the overridden update method for this applet -- update is used to 
 * eliminate the flicker that happens with repainting an image from scratch.
 * 
 **************************************************************************/
	public void update(Graphics g)
	{
    notebook.paint(g);
  }
	public void paint(Graphics g)
	{
    notebook.paint(g);
  }
  	
	/************************************************************************
	/*
	/* This method is called whenever an action is performed on the applet,
	/* specifically whenever one of the buttons on the applet is pressed
	/* 
	/************************************************************************/
	public void actionPerformed(ActionEvent event)
	{
		Object src = event.getSource();
    if (src instanceof Button)
		{
      if (src == button1) notebook.button_symbol();
      if (src == button2) notebook.button_0('2');
      if (src == button3) notebook.button_0('3');
      if (src == button4) notebook.button_0('4');
      if (src == button5) notebook.button_0('5');
      if (src == button6) notebook.button_0('6');
      if (src == button7) notebook.button_0('7');
      if (src == button8) notebook.button_0('8');
      if (src == button9) notebook.button_0('9');
      if (src == button0) notebook.button_space();

      if (src == buttonRoll) notebook.button_nextword();
      if (src == buttonEnter) notebook.button_enter();
      if (src == buttonUp) notebook.button_up();
      if (src == buttonDown) notebook.button_down();
      if (src == buttonLeft) notebook.button_left();
      if (src == buttonRight) notebook.button_right();
      if (src == buttonCenter) notebook.button_center();
      if (src == buttonClear) notebook.button_clear();
      if (notebook.dirty)
        repaint();
   	}			
  }//end of actionPerformed method

/****************************************************************************
 * 
 * The following method handles all of the key events that occurs when a user
 * enters values from the keyboard. It accepts an Event object and an integer
 * representing the key pressed as arguments.
 * 
 * It should be noted that in order to accept keys entered to the lcdDisplay,
 * the applet must be in focus.
 * 
 ***************************************************************************/
	public boolean keyDown(Event evt, int key) 
	{
		return true;				//indicate successful operation
	}
	
/****************************************************************************
 * 
 * The following methods are overridden for the timer Thread, as this applet
 * implements Runnable. 
 * 
 ****************************************************************************/
/*
	//overridden start method
	public void start()
	{
	}
	
	//overridden stop method
	public void stop()
    {
    }
	
	//overridden run method
	public void run()
	{
	}	
*/
}				//end of calc class