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Why JTextArea is small?

I try to make a simple app in SWING: using BorderLayout layout on the JFrame, i put on SOUTH an executing button, on WEST a panel that contains a combobox and on EAST a panel that contains 2 JTextAreas. The problem is, both JTextArea are damn small. Any help and explanation will be welcomed.
This is the code for the panel with the 2 text areas
package cipher;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.border.Border;
class TextPanel extends JPanel {
private JTextArea inputArea, outputArea;
public TextPanel() {
initSize();
initTextArea();
initBorder();
initLayout();
packing();
}
private void packing() {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.weighty = 1;
add(inputArea,gbc);
gbc.gridx = 0;
gbc.gridy = 1;
gbc.weightx = 1;
gbc.weighty = 1;
add(outputArea,gbc);
}
private void initBorder() {
Border outer = BorderFactory.createEmptyBorder(5, 5, 5, 5);
Border inner = BorderFactory.createTitledBorder("Text");
setBorder(BorderFactory.createCompoundBorder(outer,inner));
}
private void initLayout() {
setLayout(new GridBagLayout());
}
private void initTextArea() {
inputArea = new JTextArea();
inputArea.setPreferredSize(new Dimension(385,400));
outputArea = new JTextArea();
outputArea.setPreferredSize(new Dimension(385,400));
}
private void initSize() {
Dimension size = getPreferredSize();
size.width = 390;
setPreferredSize(size);
}
}
I've tried using setSize(x,y) but without success. I've tried using JTextArea(rows,columns) but without success. I've used even setPreferredSize with a Dimension but no succeed.

The probable cause of your issue is the container area is smaller than the preferred size of the text area, GridBagLayout will then default to the minimum size instead.
This is a good example of why you should avoid setting these properties directly and instead make use of the layout manager and the components properties.
To start with, make use of the JTextArea's column and rows properties. This will make a better "guess" at the amount of space it needs to display text to fit within these confines.
Second, use GridBagConstraints#fill to override GridBagLayout and force it to make use of the available space
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.border.Border;
import javax.swing.border.LineBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TextPanel());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TextPanel extends JPanel {
private JTextArea inputArea, outputArea;
public TextPanel() {
initTextArea();
initBorder();
initLayout();
packing();
}
private void packing() {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(inputArea, gbc);
gbc.gridx = 0;
gbc.gridy = 1;
gbc.weightx = 1;
gbc.weighty = 1;
gbc.fill = GridBagConstraints.BOTH;
add(outputArea, gbc);
}
private void initBorder() {
Border outer = BorderFactory.createEmptyBorder(5, 5, 5, 5);
Border inner = BorderFactory.createTitledBorder("Text");
setBorder(BorderFactory.createCompoundBorder(outer, inner));
}
private void initLayout() {
setLayout(new GridBagLayout());
}
private void initTextArea() {
// The borders are just here so you can see the different text areas
inputArea = new JTextArea(10, 20);
inputArea.setBorder(new LineBorder(Color.BLACK));
outputArea = new JTextArea(10, 20);
outputArea.setBorder(new LineBorder(Color.BLACK));
}
}
}
I'd also change...
inputArea = new JTextArea(10, 20);
inputArea.setBorder(new LineBorder(Color.BLACK));
outputArea = new JTextArea(10, 20);
outputArea.setBorder(new LineBorder(Color.BLACK));
and make use of JScrollPanes instead of LineBorder

Debugging GridBagLayout - components clumped to center

I'm trying to get the following layout
Label..................NumericField
Label2................NumericField
Label3333..........NumericField
Basically the (.) dots would be empty space. I had tried GridBagLayout with making the label's gridwidth as 5 and the NumericField's gridwidth as 1. I'm posting the code below. But I don't see the desired result and I see all components aligned at the center instead of Labels being at left border and NFs being at right border.
For Labels:
GridBagConstraints localC = new GridBagConstraints();
localC.anchor = GridBagConstraints.FIRST_LINE_START;
//localC.fill = GridBagConstraints.HORIZONTAL;
localC.weightx = 1.0;
localC.weighty = 1.0;
localC.gridx = 0;
localC.gridy = 0;
localC.gridheight = 1;
localC.gridwidth = 5;
localC.insets = new Insets(0, 0, 0, 0);
For NumericFields
localC.anchor = GridBagConstraints.RELATIVE;
localC.weightx = 0.5;
localC.weighty = 0.5;
localC.gridx = 1;
localC.gridy = 0;
localC.gridheight = 1;
localC.gridwidth = 1;
I'm new to JAVA and struggling with layouts generally.

Add a value to the Insets right property, which will add that number of pixels to the right side of the column. You could also use GridBagConstraints#anchor set to GridBagConstraints.WEST, which will force the components in the columns to be positioned on the left hand side of the "column", this ensures that when a component in the column is wider, they won't be laid out in the middle of the resulting space.
gridwidth determines how a given cell will span across multiple columns, but if there are no other components in the resulting columns, they are discard (defaulted to 0), so in your layout, it's meaningless.
See How to Use GridBagLayout more details
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.anchor = GridBagConstraints.WEST;
gbc.insets = new Insets(0, 0, 0, 12);
add(new JLabel("Label"), gbc);
gbc.gridy++;
add(new JLabel("Label2"), gbc);
gbc.gridy++;
add(new JLabel("Label3333"), gbc);
gbc.gridx = 1;
gbc.gridy = 0;
gbc.insets = new Insets(0, 0, 0, 0);
add(new JTextField(10), gbc);
gbc.gridy++;
add(new JTextField(10), gbc);
gbc.gridy++;
add(new JTextField(10), gbc);
}
}
}

GridBagLayout not getting expected result

Trying to understand how the GridBagLayout for Java works. Never used it before so its probably a stupid error that I've made.
My objective is to place a JLabel at the top center of the page. I've been using the java tutorials on Oracle but have had no luck. It seems the label remains in the center of the page. (center as in dead center of the x and y graph).
From what I understood, if I set the gridx and gridy constraint to 0, the compiler will look at the top, first row of the program and place the text their. I then used the PAGE START anchor to place the text in the center of the page. I'm not entirely sure what the weightx and weighty function does in my defence.
import javax.swing.*;
import java.awt.*;
class test
{
public static void main (String Args [])
{
//frame and jpanel stuff
JFrame processDetail = new JFrame("Enter information for processes");
JPanel panelDetail = new JPanel(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
//label to add on top centre
JLabel label = new JLabel("LOOK AT ME");
//set size of frame and operation
processDetail.setSize(500,500);
processDetail.setDefaultCloseOperation(processDetail.EXIT_ON_CLOSE);
//add the label to panel
c.fill = GridBagConstraints.HORIZONTAL;
c.anchor = GridBagConstraints.PAGE_START;
c.weightx = 0; //not sure what this does entirely
c.gridx = 0; //first column
c.gridy = 0; //first row
panelDetail.add(label, c);
processDetail.add(panelDetail);
processDetail.setVisible(true);
}
}

You're only adding one thing to the GBL using container, and so it will be centered. If you add a 2nd component below your JLabel, the JLabel will show up at the top. For example,
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.*;
public class Test2 {
private static void createAndShowGui() {
JPanel mainPanel = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.gridheight = 1;
gbc.gridwidth = 1;
gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.fill = GridBagConstraints.BOTH;
gbc.anchor = GridBagConstraints.PAGE_START;
mainPanel.add(new JLabel("Look at me!", SwingConstants.CENTER), gbc);
gbc.gridy = 1;
gbc.gridheight = 10;
gbc.gridwidth = 10;
mainPanel.add(Box.createRigidArea(new Dimension(400, 400)), gbc);
JFrame frame = new JFrame("Test2");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Myself, I'd use BorderLayout if I wanted my JLabel to be at the top.

Dynamicly adding JPanels to a JFrame

This is my first question inhere, so please bear with me :)
Im working on a dynamic part of a GUI, and for some reason its teasing me.
The class is opened in a new window after login.
What I want, is for a new JPanel to be built and added to 'container' every time the "add player" button is clicked. It is supposed to put them below eachother, yet all it does is to add one button on the first click, and then the rest of the clicks afterwards does nothing.
Any help is appreciated :)
package Gui;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JFrame;
//import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
#SuppressWarnings("serial")
public class TeamManagerGUI extends JFrame implements ActionListener
{
// private JLabel pNameLabel = new JLabel("Player Name: "),
// pSchoolLabel = new JLabel("School: ");
// private JTextField pNameField = new JTextField(),
// pSchoolField = new JTextField();
private JButton addButton = new JButton("Add Player"),
removeButton = new JButton("Remove player");
private JPanel container = new JPanel(),
playerContainer = new JPanel();
int frameCounter = 1;
public TeamManagerGUI()
{
super("Team Manager User Interface");
setSize(1200,800);
setDefaultCloseOperation(EXIT_ON_CLOSE);
container.setLayout(new GridBagLayout());
playerContainer.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
gbc.insets = new Insets(3,3,3,3);
addButton.addActionListener(this);
container.add(addButton,gbc);
gbc.gridx = 1;
gbc.gridy = 0;
gbc.insets = new Insets(3,3,3,3);
container.add(removeButton,gbc);
this.add(container);
}
public void playerFrame()
{
GridBagConstraints gbc = new GridBagConstraints();
playerFrameArr.add(new JPanel());
gbc.gridx = 0;
gbc.gridy = 0;
playerContainer.add(new JButton("LABEL"),gbc);
gbc.gridx = 1;
gbc.gridy = 0;
playerContainer.add(new JButton("BUTTON"),gbc);
gbc.gridx = 0;
gbc.gridy = frameCounter+1;
container.add(playerContainer,gbc);
System.out.println(frameCounter);
frameCounter++;
}
public void addPlayerRow()
{
playerFrame();
container.revalidate();
container.repaint();
}
public void removePlayerRow()
{
//Not yet implemented
}
public void actionPerformed(ActionEvent ae)
{
if(ae.getSource() == addButton)
{
addPlayerRow();
}
if(ae.getSource() == removeButton)
{
//Not yet implemented
}
}
}

You are adding the playerContainer again and again. I think you should actually use the newly created JPanel. This one should be populated and added to the main container.
Adding a single panel multiple times will not render properly as this screws up the layout. I think you need to keep a reference to the new JPanel and fill this one with your layout and the buttons.
I am thinking something like this:
public void playerFrame()
{
GridBagConstraints gbc = new GridBagConstraints();
JPanel newPanel = new JPanel(new GridBagLayout());
playerFrameArr.add(newPanel);
gbc.gridx = 0;
gbc.gridy = 0;
newPanel.add(new JButton("LABEL"), gbc);
gbc.gridx = 1;
gbc.gridy = 0;
newPanel.add(new JButton("BUTTON"), gbc);
gbc.gridx = 0;
gbc.gridy = frameCounter + 1;
container.add(newPanel, gbc);
System.out.println(frameCounter);
frameCounter++;
}

Java/Swing: Trying to get BorderLayout to play nice with GridBagLayout

I'd like to have a window that has 3 menus, one tied to the left, another tied to the center and the last one tied to the right. Like this:
--------------------------------------------
-toolbar1---------toolbar2---------toolbar3-
--------------------------------------------
- -
- rest of the window does something here -
The problem I'm having is that this is the result I get:
--------------------------------------------
---------toolbar1toolbar2toolbar3-----------
--------------------------------------------
- -
- rest of the window does something here -
Here's some sample code (compiles and shows the problem):
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TestClass extends JFrame {
public TestClass() {
super("test");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
final JPanel upper = new JPanel();
upper.setLayout(new GridBagLayout());
final GridBagConstraints gbc = new GridBagConstraints();
final JButton toolbar1 = new JButton("toolbar1");
final JButton toolbar2 = new JButton("toolbar2");
final JButton toolbar3 = new JButton("toolbar3");
gbc.gridx = 0;
gbc.gridy = 0;
gbc.anchor = GridBagConstraints.WEST;
upper.add(toolbar1, gbc);
gbc.gridx = 1;
gbc.anchor = GridBagConstraints.CENTER;
upper.add(toolbar2, gbc);
gbc.gridx = 2;
gbc.anchor = GridBagConstraints.EAST;
upper.add(toolbar3, gbc);
add(upper, BorderLayout.NORTH);
final JPanel something = new JPanel();
something.setBackground(Color.WHITE);
something.setPreferredSize(new Dimension(600, 600));
something.repaint();
add(something, BorderLayout.CENTER);
pack();
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String[] args) {
final TestClass test = new TestClass();
}
}
How can I fix it? I thought that by setting the anchor in the GridBagConstraints I'd take care of it, but that didn't work.

You forgot to add :
gbc.weightx = 1.0;
gbc.weighty = 1.0;
Your changed code should look like :
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TestClass extends JFrame {
public TestClass() {
super("test");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
final JPanel upper = new JPanel();
GridBagLayout gridbag = new GridBagLayout();
upper.setLayout(gridbag);
GridBagConstraints gbc = new GridBagConstraints();
final JButton toolbar1 = new JButton("toolbar1");
final JButton toolbar2 = new JButton("toolbar2");
final JButton toolbar3 = new JButton("toolbar3");
gbc.gridx = 0;
gbc.gridy = 0;
gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.anchor = GridBagConstraints.WEST;
upper.add(toolbar1, gbc);
gbc.gridx = 1;
gbc.anchor = GridBagConstraints.CENTER;
upper.add(toolbar2, gbc);
gbc.gridx = 2;
gbc.anchor = GridBagConstraints.EAST;
gbc.gridwidth = GridBagConstraints.REMAINDER;
upper.add(toolbar3, gbc);
add(upper, BorderLayout.NORTH);
final JPanel something = new JPanel();
something.setBackground(Color.WHITE);
something.setPreferredSize(new Dimension(600, 600));
something.repaint();
add(something, BorderLayout.CENTER);
pack();
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String[] args) {
final TestClass test = new TestClass();
}
}
It works.

If your toolbar looks like a BorderLayout (WEST, CENTER, EAST), why not use a BorderLayout instead of a GridBagLayout?
Anyway, if you insist on using GridBagLayout, set the weightx constraint for toolbar2 to 1. This tells the layout manager that, if more room is available, it should give it all to toolbar2.
gbc.weightx = 1;
upper.add(toolbar2, gbc);
gbc.weightx = 0;