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AWT FlowLayout Class

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FlowLayout

Introduction

The class FlowLayout components in a left-to-right flow.

Class declaration

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

public class FlowLayout
   extends Object
      implements LayoutManager, Serializable

Field

Following are the fields for java.awt.BorderLayout class:

  • static int CENTER — This value indicates that each row of components should be centered.
  • static int LEADING — This value indicates that each row of components should be justified to the leading edge of the container’s orientation, for example, to the left in left-to-right orientations.
  • a static int LEFT — This value indicates that each row of components should be left-justified.
  • static int RIGHT — This value indicates that each row of components should be right-justified.
  • static int TRAILING — This value indicates that each row of components should be justified to the trailing edge of the container’s orientation, for example, to the right in left-to-right orientations.

Class constructors

S.N.Constructor & Description
1FlowLayout()Constructs a new FlowLayout with a centered alignment and a default 5-unit horizontal and vertical gap.
2FlowLayout(int align)Constructs a new FlowLayout with the specified alignment and a default 5-unit horizontal and vertical gap.
3FlowLayout(int align, int hgap, int vgap)Creates a new flow layout manager with the indicated alignment and the indicated horizontal and vertical gaps.

Class methods

S.N.Method & Description
1void addLayoutComponent(String name, Component comp)Adds the specified component to the layout.
2int getAlignment()Gets the alignment for this layout.
3int getHgap()Gets the horizontal gap between components.
4int getVgap()Gets the vertical gap between components.
5void layoutContainer(Container target)Lays out the container.
6Dimension minimumLayoutSize(Container target)Returns the minimum dimensions needed to layout the visible components contained in the specified target container.
7Dimension preferredLayoutSize(Container target)Returns the preferred dimensions for this layout given the visible components in the specified target container.
8void removeLayoutComponent(Component comp)Removes the specified component from the layout.
9void setAlignment(int align)Sets the alignment for this layout.
10void setHgap(int hgap)Sets the horizontal gap between components.
11void setVgap(int vgap)Sets the vertical gap between components.
12String toString()Returns a string representation of this FlowLayout object and its values.

Methods inherited

This class inherits methods from the following classes:

  • java.lang.Object

FlowLayout Example

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

package com.adglob.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.showFlowLayoutDemo();       
   }
      
   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 Adglob AWT Tutorial.");

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

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

   private void showFlowLayoutDemo(){
      headerLabel.setText("Layout in action: FlowLayout");      

      Panel panel = new Panel();
      panel.setBackground(Color.darkGray);
      panel.setSize(200,200);
      FlowLayout layout = new FlowLayout();
      layout.setHgap(10);              
      layout.setVgap(10);
      panel.setLayout(layout);        
      panel.add(new Button("OK"));
      panel.add(new Button("Cancel"));       

      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\adglob\gui\AwtlayoutDemo.java

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

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

Verify the following output

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