WEB PROGRAMMING 2

1. 1.4 USE LAYOUT1.4 USE LAYOUT
MANAGERMANAGER

2.  By the end of the class, student should be able to:
◦ Define the use of layout manager in AWT
◦ Use layout manager in AWT:
 FlowLayout
 GridLayout
 BorderLayout
 BoxLayout
◦ Write java program using layout manager

3.  The UI components are placed in
containers.
 Each container has a layout manager to
arrange the GUI components within
the container.

4.  FlowLayout
 GridLayout
 BorderLayout
 BoxLayout

5. container.setLayout(new
SpecificLayout());
container.setLayout(new
SpecificLayout());
setLayout(new SpecificLayout());setLayout(new SpecificLayout());
Set the layout manager
here
Set the layout manager
here
AWT
SWING

6.  Simplest and most basic layout manager
 Components arranged in container from left to
right in the order in which they were added
 When edge of container reached, continues on
next line
 Can determine the gap between components in
pixels.

7.  Three constant (alignment):
◦ FlowLayout.RIGHT
◦ FlowLayout.LEFT
◦ FlowLayout.CENTER

8. FlowLayout.CENTER
FlowLayout.RIGHT
FlowLayout.LEFT

9.  public FlowLayout(int align, int hGap, int vGap)
Constructs a new FlowLayout with a specified alignment,
horizontal gap and vertical gap. The gaps are the distances in
pixel between components.
 public FlowLayout(int alignment)
Constructs a new FlowLayout with a specified alignment and a
default gap of 5 pixels for both horizontal and vertical.
 public FlowLayout()
Constructs a new FlowLayout with a default center alignment
and a default gap of 5 pixels for both horizontal and vertical.

10. import java.awt.*;
import javax.swing.*;
public class TestFlowLayout extends JFrame
{
public TestFlowLayout()
{
super(“Create FlowLayout");
Container c = getContentPane();
c.setLayout(new FlowLayout(FlowLayout.LEFT,20,10));
for (int i=1; i<9;i++)
c.add(new Button("button "+i));
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestFlowLayout s = new TestFlowLayout();
s.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
10
20

11.  Divides container into a grid
 Components placed in rows and columns
 All components have same width and height
◦ Added starting from top left, then from left to right
◦ When row full, continues on next row, left to right

12.  public GridLayout()
Construct a new GridLayout with one column
in a single row.
 public GridLayout(int rows,
int columns)
Constructs a new GridLayout with the
specified number of rows and columns.

13.  public GridLayout(int rows, int
columns, int hGap, int vGap)
Constructs a new GridLayout with the
specified number of rows and columns,
along with specified horizontal and vertical
gaps between components.

14. import java.awt.*;
import javax.swing.*;
public class TestGridLayout extends JFrame
{
public TestGridLayout()
{
super(“Create GridLayout");
Container s = getContentPane();
s.setLayout(new GridLayout(3,2,20,10));
for (int i=1; i<7;i++)
s.add(new Button("button "+i));
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestGridLayout t = new TestGridLayout();
t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

15.  Divides the window into 5 areas:
◦ BorderLayout.NORTH - North
◦ BorderLayout. SOUTH - South
◦ BorderLayout. EAST - East
◦ BorderLayout. WEST - West
◦ BorderLayout. CENTER - Center

16.  public BorderLayout()
Construct a new BorderLayout without
horizontal or vertical gaps
 public BorderLayout(int hGap,
int vGap)
Constructs a new BorderLayout with the
specified horizontal and vertical gaps
between the components.

17. import java.awt.*;
import javax.swing.*;
public class TestBorderLayout extends JFrame
{
public TestBorderLayout()
{
super(“Create BorderLayout");
Container s = getContentPane();
s.setLayout(new BorderLayout(20,10));
Button bNorth = new Button(“North");
Button bSouth = new Button(“South");
Button bEast = new Button(“East");
Button bWest = new Button(“West");
Button bCenter = new Button(“Center");
s.add(bNorth,BorderLayout.NORTH);
s.add(bSouth,BorderLayout.SOUTH);
s.add(bEast,BorderLayout.EAST);
s.add(bWest,BorderLayout.WEST);
s.add(bCenter,BorderLayout.CENTER);
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestBorderLayout t = new TestBorderLayout();
t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

18. import java.awt.*;
import javax.swing.*;
public class TestBorderLayout extends JFrame
{
public TestBorderLayout()
{
super(“Create BorderLayout");
Container s = getContentPane();
s.setLayout(new BorderLayout(20,10));
Button bNorth = new Button(“North");
Button bSouth = new Button(“South");
Button bEast = new Button(“East");
Button bWest = new Button(“West");
Button bCenter = new Button(“Center");
//s.add(bNorth,BorderLayout.NORTH);
s.add(bSouth,BorderLayout.SOUTH);
s.add(bEast,BorderLayout.EAST);
s.add(bWest,BorderLayout.WEST);
s.add(bCenter,BorderLayout.CENTER);
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestBorderLayout t = new TestBorderLayout();
t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

19. import java.awt.*;
import javax.swing.*;
public class TestBorderLayout extends JFrame
{
public TestBorderLayout()
{
super(“Create BorderLayout");
Container s = getContentPane();
s.setLayout(new BorderLayout(20,10));
Button bNorth = new Button(“North");
Button bSouth = new Button(“South");
Button bEast = new Button(“East");
Button bWest = new Button(“West");
Button bCenter = new Button(“Center");
s.add(bNorth,BorderLayout.NORTH);
s.add(bSouth,BorderLayout.SOUTH);
//s.add(bEast,BorderLayout.EAST);
s.add(bWest,BorderLayout.WEST);
s.add(bCenter,BorderLayout.CENTER);
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestBorderLayout t = new TestBorderLayout();
t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

20. import java.awt.*;
import javax.swing.*;
public class TestBorderLayout extends JFrame
{
public TestBorderLayout()
{
super(“Create BorderLayout");
Container s = getContentPane();
s.setLayout(new BorderLayout(20,10));
Button bNorth = new Button(“North");
Button bSouth = new Button(“South");
Button bEast = new Button(“East");
Button bWest = new Button(“West");
Button bCenter = new Button(“Center");
//s.add(bNorth,BorderLayout.NORTH);
s.add(bSouth,BorderLayout.SOUTH);
//s.add(bEast,BorderLayout.EAST);
//s.add(bWest,BorderLayout.WEST);
s.add(bCenter,BorderLayout.CENTER);
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestBorderLayout t = new TestBorderLayout();
t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

21. import java.awt.*;
import javax.swing.*;
public class TestBorderLayout extends JFrame
{
public TestBorderLayout()
{
super(“Create BorderLayout");
Container s = getContentPane();
s.setLayout(new BorderLayout(20,10));
Button bNorth = new Button(“North");
Button bSouth = new Button(“South");
Button bEast = new Button(“East");
Button bWest = new Button(“West");
Button bCenter = new Button(“Center");
s.add(bNorth,BorderLayout.NORTH);
s.add(bSouth,BorderLayout.SOUTH);
s.add(bEast,BorderLayout.EAST);
s.add(bWest,BorderLayout.WEST);
//s.add(bCenter,BorderLayout.CENTER);
setSize(350,200);
setVisible(true);
}
public static void main(String[] arg)
{
TestBorderLayout t = new TestBorderLayout();
t.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

22.  A layout manager that allows multiple
components to be laid out either vertically
or horizontally.
 The value of axis can be one of the
following:
◦ BoxLayout.X_AXIS
◦ BoxLayout.Y_AXIS
◦ BoxLayout.LINE_AXIS
◦ BoxLayout.PAGE_AXIS

23.  4 layout manager: FlowLayout, BorderLayout,
GridLayout and BoxLayout.