Re: align Swing JLabels and JTextFields vertically with

From:

Knute Johnson <nospam@knutejohnson.com>

Newsgroups:

comp.lang.java.programmer

Date:

Thu, 21 Apr 2011 16:47:25 -0700

Message-ID:

<hm3sp.33733$Ay5.30278@newsfe07.iad>

How about this? One thing I don't understand is how SpringLayout
determines sizes.

import java.awt.*;
import javax.swing.*;
import javax.swing.border.*;

public class test extends JPanel {
     JLabel l1,l2,l3;
     JTextField tf1,tf2,tf3;

     public test() {
         super(new GridBagLayout());

         GridBagConstraints c = new GridBagConstraints();
         c.fill = GridBagConstraints.BOTH;
         c.weightx = c.weighty = 1.0;
         c.gridx = 0;

         SpringLayout spring = new SpringLayout();

         JPanel p1 = new JPanel(spring);
         p1.setBorder(BorderFactory.createTitledBorder("Panel 1"));
         add(p1,c);

         l1 = new JLabel("Label1");
         spring.putConstraint(SpringLayout.EAST,l1,-2,
          SpringLayout.HORIZONTAL_CENTER,p1);
         spring.putConstraint(SpringLayout.VERTICAL_CENTER,l1,0,
          SpringLayout.VERTICAL_CENTER,p1);
         tf1 = new JTextField("this is text field 1",20);
         spring.putConstraint(SpringLayout.WEST,tf1,2,
          SpringLayout.HORIZONTAL_CENTER,p1);
         spring.putConstraint(SpringLayout.VERTICAL_CENTER,tf1,0,
          SpringLayout.VERTICAL_CENTER,p1);

         p1.add(l1);
         p1.add(tf1);

         JPanel p2 = new JPanel(spring);
         p2.setBorder(BorderFactory.createTitledBorder("Panel 3"));
         add(p2,c);

         l2 = new JLabel("************ LONG LABEL ***********");
         spring.putConstraint(SpringLayout.EAST,l2,-2,
          SpringLayout.HORIZONTAL_CENTER,p2);
         spring.putConstraint(SpringLayout.VERTICAL_CENTER,l2,0,
          SpringLayout.VERTICAL_CENTER,p2);
         tf2 = new JTextField("Short Textfield");
         spring.putConstraint(SpringLayout.WEST,tf2,2,
          SpringLayout.HORIZONTAL_CENTER,p2);
         spring.putConstraint(SpringLayout.VERTICAL_CENTER,tf2,0,
          SpringLayout.VERTICAL_CENTER,p2);

         p2.add(l2);
         p2.add(tf2);

         JPanel p3 = new JPanel(spring);
         p3.setBorder(BorderFactory.createTitledBorder("Panel 3"));
         add(p3,c);

         l3 = new JLabel("Label 3");
         spring.putConstraint(SpringLayout.EAST,l3,-2,
          SpringLayout.HORIZONTAL_CENTER,p3);
         spring.putConstraint(SpringLayout.VERTICAL_CENTER,l3,0,
          SpringLayout.VERTICAL_CENTER,p3);

         tf3 = new JTextField("TextField 3",30);
         spring.putConstraint(SpringLayout.WEST,tf3,2,
          SpringLayout.HORIZONTAL_CENTER,p3);
         spring.putConstraint(SpringLayout.VERTICAL_CENTER,tf3,0,
          SpringLayout.VERTICAL_CENTER,p3);

         p3.add(l3);
         p3.add(tf3);

System.out.println(spring.maximumLayoutSize(p3));
System.out.println(spring.minimumLayoutSize(p3));
System.out.println(spring.preferredLayoutSize(p3));
     }

     public static void main(String[] args) {
         EventQueue.invokeLater(new Runnable() {
             public void run() {
                 JFrame f = new JFrame();
                 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                 test t = new test();
                 f.add(t,BorderLayout.CENTER);
                 f.setSize(600,450);
                 f.setVisible(true);
             }
         });
     }
}

--

Knute Johnson
s/knute/nospam/