Here is sample tutorial to increase JTextArea font size using JSlider.
javax.swing.*: For JFrame, JTextArea, JSlider components.
java.awt.*: For GridLayout, Font
javax.swing.event.*: For ChangeListener, ChangeEvent
JTextArea: Holds text of multiple lines of text.
jt.setLineWrap(true): Proceed to next line, when reached to end ignoring words.
jt.setWrapStyleWord(true): When, word reaches end of line incompletely, entire word settles in a next line. As observed in Notepad.
JScrollPane: For JTextArea, when size is increased, JTextArea looks odd, so scrollpane is added.
JSlider: Observed in Media players, used in adjusting progress. Here used for increasing font size.
jl.setValue(20): Font size of JTextArea is 20 initially. See above.
ChangeEvent: Generated when user changes JSlider value.
ChangeListener: Listener for ChangeEvent.
setFont(font): Used to set font for JTextArea, takes java.awt.Font as parameter, Font class constructor consists of three parameters, font name, style, size respectively.
setExtendedState(MAXIMIZED_BOTH): Make frame maximized both the sides.
import javax.swing.*;
import java.awt.*;
import javax.swing.event.*;
class JTextAreaFont extends JFrame
{
JTextArea jt;
JScrollPane js;
JSlider jl;
public JTextAreaFont()
{
setTitle("Increase JTextArea Font Size");
setLayout(new GridLayout());
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
jt=new JTextArea();
jt.setLineWrap(true);
jt.setWrapStyleWord(true);
jt.setFont(new Font("Times New Roman",Font.BOLD,20));
js=new JScrollPane(jt);
add(js);
jl=new JSlider(1,200);
jl.setValue(20);
add(jl);
jl.addChangeListener(new ChangeListener(){
public void stateChanged(ChangeEvent ce)
{
jt.setFont(new Font("Times New Roman",Font.BOLD,jl.getValue()));
}
});
setExtendedState(MAXIMIZED_BOTH);
}
public static void main(String args[])
{
new JTextAreaFont();
}
}
javax.swing.*: For JFrame, JTextArea, JSlider components.
java.awt.*: For GridLayout, Font
javax.swing.event.*: For ChangeListener, ChangeEvent
JTextArea: Holds text of multiple lines of text.
jt.setLineWrap(true): Proceed to next line, when reached to end ignoring words.
jt.setWrapStyleWord(true): When, word reaches end of line incompletely, entire word settles in a next line. As observed in Notepad.
JScrollPane: For JTextArea, when size is increased, JTextArea looks odd, so scrollpane is added.
JSlider: Observed in Media players, used in adjusting progress. Here used for increasing font size.
jl.setValue(20): Font size of JTextArea is 20 initially. See above.
ChangeEvent: Generated when user changes JSlider value.
ChangeListener: Listener for ChangeEvent.
setFont(font): Used to set font for JTextArea, takes java.awt.Font as parameter, Font class constructor consists of three parameters, font name, style, size respectively.
setExtendedState(MAXIMIZED_BOTH): Make frame maximized both the sides.