我在我的程序中将 JTexfield 居中时遇到问题。Textfield 没有与 JButton 对齐。我试过使用 x.setHoriontalAlignment(JTextfield.CENTER); 但无济于事。有任何想法吗?
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.JPanel;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.GridBagLayout;
public class WidgetProject implements ActionListener
{
//class constants
private static final Color BUTTON_COLOUR1 = Color.WHITE;
private static final int BUTTON_HEIGHT = 75;
private static final int BUTTON_WIDTH = 400;
private static final int TEXTFIELD_HEIGHT = 400;
private static final int TEXTFIELD_WIDTH = 50;
private static final String SECONDS_PER_MINUTE = "Seconds to Minutes or Minutes to Seconds";
private static final String BUTTON2_MODIFIED_LABEL = "yes";
private static final String POUNDS_PER_KILOGRAM = "Pounds to Kilograms or Kilograms to Pounds";
private static final String CHANGE_MY_LABEL = "1";
private static final int HEIGHT = 400;
private static final int WIDTH = 400;
// instance fields
private JButton button1;
private JButton button2;
private JButton button3;
private JButton button4;
private JFrame frame;
private JTextField textInput;
private JPanel panel;
/**
* A free-standing frame with two buttons.
*
* @param title the title of this frame
*/
public WidgetProject(String title)
{
// Establish the frame.
frame = new JFrame(title);
frame.setLayout(new BoxLayout(frame.getContentPane(), BoxLayout.Y_AXIS));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(WIDTH, HEIGHT));
// Establish button dimensions.
Dimension buttonDimension = new Dimension(BUTTON_WIDTH, BUTTON_HEIGHT);
// Establish Textfield dimensions.
Dimension textDimension = new Dimension(TEXTFIELD_HEIGHT, TEXTFIELD_WIDTH);
// Create and add the first button.
button1 = new JButton(SECONDS_PER_MINUTE);
button1.setActionCommand(CHANGE_MY_LABEL);
button1.addActionListener(this);
button1.setPreferredSize(buttonDimension);
button1.setMinimumSize(buttonDimension);
button1.setMaximumSize(buttonDimension);
button1.setBackground(BUTTON_COLOUR1);
frame.add(button1);
// Create and add the second button.
button2 = new JButton(POUNDS_PER_KILOGRAM);
button2.setActionCommand(CHANGE_MY_LABEL);
button2.addActionListener(this);
button2.setPreferredSize(buttonDimension);
button2.setMinimumSize(buttonDimension);
button2.setMaximumSize(buttonDimension);
button2.setBackground(BUTTON_COLOUR1);
frame.add(button2);
// Create an input text field.
textInput = new JTextField(20);
textInput.setPreferredSize(textDimension);
textInput.setMinimumSize(textDimension);
textInput.setMaximumSize(textDimension);
textInput.setHorizontalAlignment(JTextField.CENTER);
panel = new JPanel();
panel.add(textInput);
String string = textInput.getText();
// Display the frame and text field.
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.add(textInput);
} // 构造函数 ButtonDuo 结束