Question

我有以下程序。当我更改列大小，并单击任何中心，左或右对齐按钮时，如果列大小太高，则一切都会更改。我希望窗口的尺寸增大，并且面板的排列没有任何变化。有人可以提出一些见解。

package workingwithjtextfields;

import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.*;
import javax.swing.border.*;


public class WorkingwithJTextFields extends JFrame {

    private JTextField jtfMessage = new JTextField(100);
    private JTextField jtfColumn = new JTextField(5);
    private JRadioButton jrbLeft, jrbCenter, jrbRight;

    public static void main(String[] args) //Main program begins here.
    {
        JFrame frame = new WorkingwithJTextFields();//Instantiating an object.
        //frame.pack();
        frame.setTitle("Exercise 17.11");//Setting the frame title.
        frame.setSize(500, 110);//Setting the size.
        frame.setLocationRelativeTo(null);//Setting the location.
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);// Default closing options.
        frame.setVisible(true);//Setting visibility to true.

    }//End of main program

    public WorkingwithJTextFields() {

        // jtfMessage.setColumns(100);
        final JPanel parent = new JPanel();
        parent.setLayout(new GridLayout(2, 1, 3, 3));

        final JPanel p1 = new JPanel();
        p1.setLayout(new FlowLayout(FlowLayout.CENTER, 30, 0));

        p1.add(new JLabel("TextField", SwingConstants.CENTER));

        jtfMessage = new JTextField("Type anything", SwingConstants.RIGHT);
        jtfMessage.setHorizontalAlignment(SwingConstants.CENTER);
        jtfMessage.setColumns(30);
        p1.add(jtfMessage);

        parent.add(p1);

        JPanel jpRadioButtons = new JPanel();
        jpRadioButtons.setLayout(new GridLayout(1, 3));
        jpRadioButtons.add(jrbLeft = new JRadioButton("Left"));
        jpRadioButtons.add(jrbCenter = new JRadioButton("Center"));
        jpRadioButtons.add(jrbRight = new JRadioButton("Right"));
        jpRadioButtons.setBorder(new TitledBorder("Horizontal Border"));

        final JPanel p2 = new JPanel();
        p2.setLayout(new GridLayout(1, 2, 1, 1));

        p2.add(jpRadioButtons);

        JPanel p3 = new JPanel();
        p3.setLayout(new GridLayout(1, 1, 1, 1));
        p3.add(new JLabel("Column Size"));

        jtfColumn = new JTextField("60", SwingConstants.RIGHT);
        jtfColumn.setHorizontalAlignment(SwingConstants.CENTER);

        p3.add(jtfColumn);
        Border lineBorder = new LineBorder(Color.LIGHT_GRAY, 1);
        p3.setBorder(lineBorder);
        p2.add(p3);
        parent.add(p2);
        add(parent);

        jrbLeft.addActionListener(
                new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        jtfMessage.setHorizontalAlignment(SwingConstants.LEFT);
                        jrbCenter.setSelected(false);
                        jrbRight.setSelected(false);
                        jtfMessage.setColumns(Integer.parseInt(jtfColumn.getText()));
                        p1.revalidate();
                        p1.repaint();

                    }
                }
        );

        jrbCenter.addActionListener(
                new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        jtfMessage.setHorizontalAlignment(SwingConstants.CENTER);
                        jrbLeft.setSelected(false);
                        jrbRight.setSelected(false);
                        jtfMessage.setColumns(Integer.parseInt(jtfColumn.getText()));
                    }
                }
        );

        jrbRight.addActionListener(
                new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        jtfMessage.setHorizontalAlignment(SwingConstants.RIGHT);
                        jrbCenter.setSelected(false);
                        jrbLeft.setSelected(false);
                        jtfMessage.setColumns(Integer.parseInt(jtfColumn.getText()));
                    }

                }
        );

    }

}

Answer 1

Java应用程序使用LayoutManagers来控制它，如果你想100％控制它，你将不得不使用像Netbeans的AbsoluteLayout这样的非标准组件，但是你必须在你的应用程序中包含它的.jar。

Answer 2

当您更改字段的列大小时，您需要在字段窗口中调用pack以使其将窗口大小调整为其包含的组件的首选大小

例如......

jrbLeft.addActionListener(
        new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                jtfMessage.setHorizontalAlignment(SwingConstants.LEFT);
                jrbCenter.setSelected(false);
                jrbRight.setSelected(false);
                jtfMessage.setColumns(Integer.parseInt(jtfColumn.getText()));
                p1.revalidate();
                SwingUtilities.getWindowAncestor(p1).pack();
                SwingUtilities.getWindowAncestor(p1).setLocationRelativeTo(null);
            }
        }
);

调整窗口大小

2 个答案: