driver.java

Java程序设计(美) David D. Riley著 机械工业出版社 书籍配套 代码

import javax.swing.*;
import java.awt.*;
import java.util.Scanner;

/** Temperature Program Director  (Figures 8.47, 8.48 and 8.49)
 *  Author: David D. Riley
 *  Date: May, 2004
 */
import javax.swing.*;
import java.awt.*;
import java.util.Scanner;
public class Driver  {
	private  JFrame  window;
	private  FahrenheitField  fahrenFld;
	private  FahrenheitSlider  fahrenSlider;
	private  JTextField  celsiusFld;

    public Driver()  {
		window = new JFrame("Fahrenheit to Celsius");
		window.setBounds(10, 10, 300, 200);
		window.setVisible(true);
		window.setLayout(null);
		fahrenFld = new FahrenheitField(125, 5, this);
		window.add(fahrenFld);
		celsiusFld = new JTextField();
		celsiusFld.setBounds(85, 120, 150, 30);
		window.add(celsiusFld, 0);
		fahrenSlider = new FahrenheitSlider(-100, 300, 0, fahrenFld);
		fahrenSlider.setBounds(125, 40, 100, 30);
		window.add(fahrenSlider, 0);
		makeAndAddLabels(window);
		window.repaint();
	}

	/**	pre:	c != null 
	 *	post:	Fahrenheit and Celsius labels have been added to the 
	 *			left of the respective fields.  
	 */
	private  void  makeAndAddLabels(JFrame f)   {
		Label celsiusLabel, fahrenLabel;	
		fahrenLabel = new Label("Fahrenheit:"); 
		fahrenLabel.setBounds(20, 5, 100, 30);
		fahrenLabel.setForeground(Color.red);
		f.add(fahrenLabel, 0);
		celsiusLabel = new Label("Celsius:"); 
		celsiusLabel.setBounds(20, 120, 60, 30);
		celsiusLabel.setForeground(Color.red);
		f.add(celsiusLabel, 0);
	}
    
	/**	pre:	celsiusFld != null  and  fahrenFld != null 
	 *	post:	celsiusFld displays the Celsius equivalent of the temperature
	 *			from fahrenFld   
	 */
	public  void  updateCelsius()   {
		double fahrenTemp;
		fahrenTemp = (new Scanner(fahrenFld.getText())).nextDouble();	
		celsiusFld.setText("" + (fahrenTemp- 32.0) * 5.0/9.0 );
		celsiusFld.repaint();
	}

	/**	pre:	fahrenFld != null  and  fahrenSlider != null 
	 *	post:	fahrenSlider is set to the value from fahrenFld   
	 */
	public  void  updateFahrenSlider()   {
		double fahrenTemp;
		fahrenTemp = (new Scanner(fahrenFld.getText())).nextDouble();	
		fahrenSlider.setValue((int)fahrenTemp);
	}
}