SWING - GridBagLayout Class
Introduction
The class GridBagLayout arranges components in a horizontal and vertical manner.
Class declaration
Following is the declaration for java.awt.GridBagLayout class:
public class GridBagLayout extends Object implements LayoutManager2, Serializable
Field
Following are the fields for java.awt.GridBagLayout class:
static int DEFAULT_SIZE -- Indicates the size from the component or gap should be used for a particular range value.
static int PREFERRED_SIZE -- Indicates the preferred size from the component or gap should be used for a particular range value.
Class constructors
S.N. | Constructor & Description |
---|---|
1 | GridBagLayout() Creates a grid bag layout manager. |
Class methods
S.N. | Method & Description |
---|---|
1 | void addLayoutComponent(Component comp, Object constraints) Adds the specified component to the layout, using the specified constraints object. |
2 | void addLayoutComponent(String name, Component comp) Adds the specified component with the specified name to the layout. |
3 | protected void adjustForGravity(GridBagConstraints constraints, Rectangle r) Adjusts the x, y, width, and height fields to the correct values depending on the constraint geometry and pads. |
4 | protected void AdjustForGravity(GridBagConstraints constraints, Rectangle r) This method is obsolete and supplied for backwards compatability only; new code should call adjustForGravity instead. |
5 | protected void arrangeGrid(Container parent) Lays out the grid. |
6 | protected void ArrangeGrid(Container parent) This method is obsolete and supplied for backwards compatability only; new code should call arrangeGrid instead. |
7 | GridBagConstraints getConstraints(Component comp) Gets the constraints for the specified component. |
8 | float getLayoutAlignmentX(Container parent) Returns the alignment along the x axis. |
9 | float getLayoutAlignmentY(Container parent) Returns the alignment along the y axis. |
10 | int[][] getLayoutDimensions() Determines column widths and row heights for the layout grid. |
11 | protected java.awt.GridBagLayoutInfo getLayoutInfo(Container parent, int sizeflag) Fills in an instance of GridBagLayoutInfo for the current set of managed children. |
12 | protected java.awt.GridBagLayoutInfo GetLayoutInfo(Container parent, int sizeflag) This method is obsolete and supplied for backwards compatability only; new code should call getLayoutInfo instead. |
13 | Point getLayoutOrigin() Determines the origin of the layout area, in the graphics coordinate space of the target container. |
14 | double[][] getLayoutWeights() Determines the weights of the layout grid's columns and rows. |
15 | protected Dimension getMinSize(Container parent, java.awt.GridBagLayoutInfo info) Figures out the minimum size of the master based on the information from getLayoutInfo(). |
16 | protected Dimension GetMinSize(Container parent, java.awt.GridBagLayoutInfo info) This method is obsolete and supplied for backwards compatability only; new code should call getMinSize instead. |
17 | void invalidateLayout(Container target) Invalidates the layout, indicating that if the layout manager has cached information it should be discarded. |
18 | void layoutContainer(Container parent) Lays out the specified container using this grid bag layout. |
19 | Point location(int x, int y) Determines which cell in the layout grid contains the point specified by (x, y). |
20 | protected GridBagConstraints lookupConstraints(Component comp) Retrieves the constraints for the specified component. |
21 | Dimension maximumLayoutSize(Container target) Returns the maximum dimensions for this layout given the components in the specified target container. |
22 | Dimension minimumLayoutSize(Container parent) Determines the minimum size of the parent container using this grid bag layout. |
23 | Dimension preferredLayoutSize(Container parent) Determines the preferred size of the parent container using this grid bag layout. |
24 | void removeLayoutComponent(Component comp) Removes the specified component from this layout. |
25 | void setConstraints(Component comp, GridBagConstraints constraints) Sets the constraints for the specified component in this layout. |
26 | String toString() Returns a string representation of this grid bag layout's values. |
Methods inherited
This class inherits methods from the following classes:
java.lang.Object
GridBagLayout Example
Create the following java program using any editor of your choice in say D:/ > SWING > com > tutorialspoint > gui >
SwingLayoutDemo.javapackage com.tutorialspoint.gui; import java.awt.*; import java.awt.event.*; import javax.swing.*; public class SwingLayoutDemo { private JFrame mainFrame; private JLabel headerLabel; private JLabel statusLabel; private JPanel controlPanel; private JLabel msglabel; public SwingLayoutDemo(){ prepareGUI(); } public static void main(String[] args){ SwingLayoutDemo swingLayoutDemo = new SwingLayoutDemo(); swingLayoutDemo.showGridBagLayoutDemo(); } private void prepareGUI(){ mainFrame = new JFrame("Java SWING Examples"); mainFrame.setSize(400,400); mainFrame.setLayout(new GridLayout(3, 1)); headerLabel = new JLabel("",JLabel.CENTER ); statusLabel = new JLabel("",JLabel.CENTER); statusLabel.setSize(350,100); mainFrame.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent windowEvent){ System.exit(0); } }); controlPanel = new JPanel(); controlPanel.setLayout(new FlowLayout()); mainFrame.add(headerLabel); mainFrame.add(controlPanel); mainFrame.add(statusLabel); mainFrame.setVisible(true); } private void showGridBagLayoutDemo(){ headerLabel.setText("Layout in action: GridBagLayout"); JPanel panel = new JPanel(); panel.setBackground(Color.darkGray); panel.setSize(300,300); GridBagLayout layout = new GridBagLayout(); panel.setLayout(layout); GridBagConstraints gbc = new GridBagConstraints(); gbc.fill = GridBagConstraints.HORIZONTAL; gbc.gridx = 0; gbc.gridy = 0; panel.add(new JButton("Button 1"),gbc); gbc.gridx = 1; gbc.gridy = 0; panel.add(new JButton("Button 2"),gbc); gbc.fill = GridBagConstraints.HORIZONTAL; gbc.ipady = 20; gbc.gridx = 0; gbc.gridy = 1; panel.add(new JButton("Button 3"),gbc); gbc.gridx = 1; gbc.gridy = 1; panel.add(new JButton("Button 4"),gbc); gbc.gridx = 0; gbc.gridy = 2; gbc.fill = GridBagConstraints.HORIZONTAL; gbc.gridwidth = 2; panel.add(new JButton("Button 5"),gbc); controlPanel.add(panel); mainFrame.setVisible(true); } }
Compile the program using command prompt. Go to D:/ > SWING and type the following command.
D:\SWING>javac com\tutorialspoint\gui\SwingLayoutDemo.java
If no error comes that means compilation is successful. Run the program using following command.
D:\SWING>java com.tutorialspoint.gui.SwingLayoutDemo
Verify the following output
![SWING GridBagLayout](/swing/images/swing_gridbaglayout.jpg)