这是一个摄氏的转化。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class CelsiusConverter implements ActionListener {
JFrame converterFrame;
JPanel converterPanel;
JTextField tempCelsius;
JLabel celsiusLabel, fahrenheitLabel;
JButton convertTemp;
public CelsiusConverter() {
converterFrame = new JFrame("Convert Celsius to Fahrenheit");
converterFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
converterFrame.setSize(new Dimension(120, 40));
converterPanel = new JPanel(new GridLayout(2, 2));
addWidgets();
converterFrame.getRootPane().setDefaultButton(convertTemp);
converterFrame.getContentPane().add(converterPanel, BorderLayout.CENTER);
converterFrame.pack();
converterFrame.setVisible(true);
}
private void addWidgets() {
tempCelsius = new JTextField(2);
celsiusLabel = new JLabel("Celsius", SwingConstants.LEFT);
convertTemp = new JButton("Convert");
fahrenheitLabel = new JLabel("Fahrenheit", SwingConstants.LEFT);
convertTemp.addActionListener(this);
converterPanel.add(tempCelsius);
converterPanel.add(celsiusLabel);
converterPanel.add(convertTemp);
converterPanel.add(fahrenheitLabel);
celsiusLabel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
fahrenheitLabel.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
}
public void actionPerformed(ActionEvent event) {
int tempFahr = (int)((Double.parseDouble(tempCelsius.getText()))
* 1.8 + 32);
fahrenheitLabel.setText(tempFahr + " Fahrenheit");
}
private static void createAndShowGUI() {
JFrame.setDefaultLookAndFeelDecorated(true);
CelsiusConverter converter = new CelsiusConverter();
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
这里和以前的还是没有太多的变化，就是复杂了一点。
其他就是这行代码了：
int tempFahr = (int)((Double.parseDouble(tempCelsius.getText()))
* 1.8 + 32);
