Java Swing GridBagLayout is a Swing layout manager that is difficult to use and needs good practice to master it. GridBagLayout lay’s out components vertically and horizontally within a grid of rows and columns that can be of different sizes. To understand GridBagLayout, its essential to know what a GridBagConstraint is ?
GridBagConstraints are used to specify how a component must be positioned within the display area of your panel. It gives you complete control to set various parameters like coordinate positions (gridx & gridy), width, height, (gridwidth & gridheight) internal padding (ipadx & ipady), external padding (insets), anchor, weightx and weighty.
Below is a Swing GridBagLayout Example that demonstrates
- How to work with the GridBagLayout and GridBagConstraints classes.
- How to create and set a gridbag layout
- how to set gridbag constraints on each component that is added to the layout.
[sourcecode language='java']
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JRadioButton;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class JavaGridNagLayoutExample {
private JTextField jtfName;
private JTextField jtfAge;
private JTextArea jtaAddress;
private JTextField jtfState;
private JTextField jtfCity;
private JRadioButton jrbMale;
private JRadioButton jrbFemale;
private JButton jbtSubmit;
public void addComponentsToPane(JFrame frame) {
Container pane = frame.getContentPane();
ButtonGroup group = new ButtonGroup();
group.add(jrbMale);
group.add(jrbFemale);
GridBagConstraints gBC = new GridBagConstraints();
gBC.fill = GridBagConstraints.HORIZONTAL;
gBC.insets = new Insets(5, 5, 0, 5);
JLabel jlbName = new JLabel(”Name : “);
gBC.gridx = 0;
gBC.gridy = 0;
pane.add(jlbName, gBC);
jtfName = new JTextField(20);
gBC.gridx = 1;
gBC.gridy = 0;
gBC.gridwidth = 2;
pane.add(jtfName, gBC);
JLabel jlbAge = new JLabel(”Age : “);
gBC.gridx = 0;
gBC.gridy = 1;
gBC.gridwidth = 1;
pane.add(jlbAge, gBC);
jtfAge = new JTextField(5);
gBC.gridx = 1;
gBC.gridy = 1;
gBC.fill = GridBagConstraints.NONE;
gBC.anchor = GridBagConstraints.WEST;
gBC.gridwidth = 2;
pane.add(jtfAge, gBC);
gBC.fill = GridBagConstraints.HORIZONTAL;
JLabel jlbSex = new JLabel(”Sex : “);
gBC.gridx = 0;
gBC.gridy = 2;
gBC.gridwidth = 1;
pane.add(jlbSex, gBC);
jrbMale = new JRadioButton(”Male”);
gBC.gridx = 1;
gBC.gridy = 2;
pane.add(jrbMale, gBC);
jrbFemale = new JRadioButton(”Female”);
gBC.gridx = 2;
gBC.gridy = 2;
pane.add(jrbFemale, gBC);
JLabel jlbAddress = new JLabel(”Address : “);
gBC.gridx = 0;
gBC.gridy = 3;
pane.add(jlbAddress, gBC);
jtaAddress = new JTextArea(5, 10);
gBC.gridx = 1;
gBC.gridy = 3;
gBC.gridwidth = 2;
pane.add(jtaAddress, gBC);
JLabel jlbCity = new JLabel(”City : “);
gBC.gridx = 0;
gBC.gridy = 4;
gBC.gridwidth = 1;
pane.add(jlbCity, gBC);
jtfCity = new JTextField(10);
gBC.gridx = 1;
gBC.gridy = 4;
gBC.gridwidth = 2;
pane.add(jtfCity, gBC);
gBC.gridwidth = 1;
JLabel jlbState = new JLabel(”State : “);
gBC.gridx = 3;
gBC.gridy = 4;
gBC.insets.right = 0;
pane.add(jlbState, gBC);
gBC.insets.right = 5;
jtfState = new JTextField(10);
gBC.gridx = 4;
gBC.gridy = 4;
pane.add(jtfState, gBC);
jbtSubmit = new JButton(”Submit”);
gBC.gridx = 4;
gBC.gridy = 5;
pane.add(jbtSubmit, gBC);
}
public static void main(String[] args) {
JavaGridNagLayoutExample test = new JavaGridNagLayoutExample();
JFrame frame = new JFrame(”GridBagLayout Demo”);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(new GridBagLayout());
test.addComponentsToPane(frame);
frame.pack();
frame.setVisible(true);
}
}
[/sourcecode]
An advantage of the GridBagLayout over GridLayout is that we can layout out components in rows and columns of different sizes.
Check GridBagLayout Class Related API
java.awt.GridBagLayout Class
java.awt.GridBagConstraints Class
You may also want to check out How to Use GridBagLayout tutorial from the Sun Java Site .
Need to show the output sample also……
Nice work, but i would be better if you set the components to have a fix size or scrollable,they expand the whole form if you enter too much data
that ok
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