AWT GridLayout Class


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Introduction

The class GridLayout arranges components in a rectangular grid.

Class declaration

Following is the declaration for java.awt.GridLayout class:

public class GridLayout
   extends Object
      implements LayoutManager, Serializable

Class constructors

S.N.Constructor & Description
1

GridLayout()

Creates a grid layout with a default of one column per component, in a single row.

2

GridLayout(int rows, int cols)

Creates a grid layout with the specified number of rows and columns.

3

GridLayout(int rows, int cols, int hgap, int vgap)

Creates a grid layout with the specified number of rows and columns.

Class methods

S.N.Method & Description
1

void addLayoutComponent(String name, Component comp)

Adds the specified component with the specified name to the layout.

2

int getColumns()

Gets the number of columns in this layout.

3

int getHgap()

Gets the horizontal gap between components.

4

int getRows()

Gets the number of rows in this layout.

5

int getVgap()

Gets the vertical gap between components.

6

void layoutContainer(Container parent)

Lays out the specified container using this layout.

7

Dimension minimumLayoutSize(Container parent)

Determines the minimum size of the container argument using this grid layout.

8

Dimension preferredLayoutSize(Container parent)

Determines the preferred size of the container argument using this grid layout.

9

void removeLayoutComponent(Component comp)

Removes the specified component from the layout.

10

void setColumns(int cols)

Sets the number of columns in this layout to the specified value.

11

void setHgap(int hgap)

Sets the horizontal gap between components to the specified value.

12

void setRows(int rows)

Sets the number of rows in this layout to the specified value.

13

void setVgap(int vgap)

Sets the vertical gap between components to the specified value.

14

String toString()

Returns the string representation of this grid layout's values.

Methods inherited

This class inherits methods from the following classes:

  • java.lang.Object

GridLayout Example

Create the following java program using any editor of your choice in say D:/ > AWT > com > tutorialspoint > gui >

AwtLayoutDemo.java
package com.tutorialspoint.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtLayoutDemo {
   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;
   private Label msglabel;

   public AwtLayoutDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtLayoutDemo  awtLayoutDemo = new AwtLayoutDemo();  
      awtLayoutDemo.showGridLayoutDemo();       
   }
      
   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      msglabel = new Label();
      msglabel.setAlignment(Label.CENTER);
      msglabel.setText("Welcome to TutorialsPoint AWT Tutorial.");

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showGridLayoutDemo(){
      headerLabel.setText("Layout in action: GridLayout");      

      Panel panel = new Panel();
      panel.setBackground(Color.darkGray);
      panel.setSize(300,300);
      GridLayout layout = new GridLayout(0,3);
      layout.setHgap(10);
      layout.setVgap(10);
      
      panel.setLayout(layout);        
      panel.add(new Button("Button 1"));
      panel.add(new Button("Button 2")); 
      panel.add(new Button("Button 3")); 
      panel.add(new Button("Button 4")); 
      panel.add(new Button("Button 5")); 
      controlPanel.add(panel);
      mainFrame.setVisible(true);  
   }
}

Compile the program using command prompt. Go to D:/ > AWT and type the following command.

D:\AWT>javac com\tutorialspoint\gui\AwtlayoutDemo.java

If no error comes that means compilation is successful. Run the program using following command.

D:\AWT>java com.tutorialspoint.gui.AwtlayoutDemo

Verify the following output

AWT GridLayout
awt_layouts.htm

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