Develop Reference

BorderLayout combined with FlowLayout: JTextArea ruins GUI (Java Swing)

I use a BorderLayout combined with a FlowLayout, which works perfectly when I set up the BorderLayout.NORTH. However, in the CENTER area I would like to add a JTextArea (to print out console), but when I create a panel, add JTextArea, after adding a panel to BorderLayout.CENTER nothing appears and became grey. I have tried several combinations and tricks, also I have checked several forum posts without luck. Here is my very simplified code (should run flawlessly, I have commented the problematic part if you remove the comment the bug present):
public static void main(String[] args) {
blogGUI();
}
public static void blogGUI() {
JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setVisible(true);
frame.setSize(700, 500);
frame.setLayout(new BorderLayout()); //a frame BorderLayout elrendezésü
JPanel panel1 = new JPanel();
//panel.setBounds(0,0,700,500);
panel1.setBackground(new java.awt.Color(255,255,255));
panel1.setVisible(true);
panel1.setSize(new Dimension(140, 30));
JPanel panel2 = new JPanel();
//panel.setBounds(0,0,700,500);
panel2.setBackground(new java.awt.Color(255,255,255));
panel2.setVisible(true);
panel2.setSize(new Dimension(140, 30));
JButton btNewEntry = new JButton("New Post");
JButton btModifyEntry = new JButton("Modify");
JButton btDeleteEntry = new JButton("Delete");
JButton btShowEntries = new JButton("List");
JButton btExit = new JButton("Exit");
JLabel lbFile = new JLabel("Open Blog:");
JLabel lbFilePath = new JLabel("Nothing selected...");
JButton btFileOpen = new JButton("Open");
btNewEntry.setPreferredSize(new Dimension(100,30));
btModifyEntry.setPreferredSize(new Dimension(100,30));
btDeleteEntry.setPreferredSize(new Dimension(100,30));
btShowEntries.setPreferredSize(new Dimension(100,30));
btExit.setPreferredSize(new Dimension(100,30));
lbFile.setPreferredSize(new Dimension(100,30));
lbFilePath.setPreferredSize(new Dimension(310,30));
btFileOpen.setPreferredSize(new Dimension(100,30));
panel1.add(btNewEntry);
panel1.add(btModifyEntry);
panel1.add(btDeleteEntry);
panel1.add(btShowEntries);
panel1.add(btExit);
panel2.add(lbFile);
panel2.add(btFileOpen);
panel2.add(lbFilePath);
JPanel cpanelNorth = new JPanel();
cpanelNorth.setBackground(new java.awt.Color(135,206,250));
cpanelNorth.setLayout(new FlowLayout());
cpanelNorth.setPreferredSize(new Dimension(500, 95));
cpanelNorth.add(panel1);
cpanelNorth.add(panel2);
frame.add(cpanelNorth, BorderLayout.NORTH);
/*Something wrong here! From this point, if this uncommented ruins the gui.*/
JPanel panel3 = new JPanel();
panel3.setLayout(new FlowLayout());
//panel.setBounds(0,0,700,500);
panel3.setBackground(new java.awt.Color(255,255,255));
//panel3.setVisible(true);
//panel3.setPreferredSize(new Dimension(30, 30));
JTextArea textArea = new JTextArea("Welcome to...!");
//textArea.setPreferredSize(new Dimension(50,50));
textArea.setBackground(new java.awt.Color(255,0,0));
panel3.add(textArea);
frame.add(panel3, BorderLayout.CENTER);

Hi Andrew Thompson and user16320675, Thanks for the quick help, this solved my issue. How can I further improve the quality the code? I had to put only one setPrefferedSize() at the JTextArea, all other places I removed (without this the window shrinks to zero)
I reduced my code
image: https://ibb.co/Xj7tYKf
I have removed allsetPrefferedSize()
I put frame.setVisible(true) at the end, and also frame.pack() at the end
Here is my code:
package bloggui;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextArea;
public class Start {
public static void main(String[] args) {
blogGUI();
}
public static void blogGUI() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
JPanel panel1 = new JPanel();
panel1.setBackground(new java.awt.Color(255,255,255));
JPanel panel2 = new JPanel();
panel2.setBackground(new java.awt.Color(255,255,255));
JButton btNewEntry = new JButton("New Post");
JButton btModifyEntry = new JButton("Modify");
JButton btDeleteEntry = new JButton("Delete");
JButton btShowEntries = new JButton("List");
JButton btExit = new JButton("Exit");
JLabel lbFile = new JLabel("Open Blog:");
JLabel lbFilePath = new JLabel("Nothing selected...");
JButton btFileOpen = new JButton("Open");
panel1.add(btNewEntry);
panel1.add(btModifyEntry);
panel1.add(btDeleteEntry);
panel1.add(btShowEntries);
panel1.add(btExit);
panel2.add(lbFile);
panel2.add(btFileOpen);
panel2.add(lbFilePath);
JPanel cpanelNorth = new JPanel();
cpanelNorth.setBackground(new java.awt.Color(135,206,250));
cpanelNorth.setLayout(new FlowLayout());
cpanelNorth.add(panel1);
cpanelNorth.add(panel2);
frame.add(cpanelNorth, BorderLayout.NORTH);
frame.pack();
JPanel panel3 = new JPanel();
panel3.setLayout(new FlowLayout());
panel3.setBackground(new java.awt.Color(135,206,250));
JTextArea textArea = new JTextArea("Welcome to...!");
textArea.setBackground(new java.awt.Color(255,255,255));
textArea.setPreferredSize(new Dimension(620, 400)); //Must not use setPreferredSize() [I must use it only once here!]
panel3.add(textArea);
frame.add(panel3, BorderLayout.CENTER);
frame.pack(); //Must be at the end
frame.setVisible(true); //Must be at the end
}
}

Why is BorderLayout not displaying properly with multiple layers?

I am setting up a UI for a blackjack helper program and while I know its not the most beautiful way to do things, it makes sense.
The layering for what seems to be the upper layers is not working properly. Any suggestions?
The left should have four layers, as should the middle and the right side should have two layers between the keypad and the enter buttons. Image is attached below.
import java.util.*;
import java.lang.*;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.text.*;
// main method, runs the program
class BlackjackHelper
{
public static void main(String\[\] args)
{
Frame21 game = new Frame21();
//pop window with rules of game
}
}
// JFrame Construction
class Frame21 extends JFrame
{
// create needed components of program
JLabel questionDisplay = new JLabel("What is your first card?");
JLabel actionDisplay = new JLabel("Enter your first card");
JLabel dealerCardText = new JLabel("Dealer's Card:");
JLabel dealerCardDisplay = new JLabel("N/A");
JLabel handOneText = new JLabel("Hand One:");
JLabel handOneDisplay = new JLabel("N/A");
JLabel handTwoText = new JLabel("Hand Two:");
JLabel handTwoDisplay = new JLabel("N/A");
JLabel statsText = new JLabel("Win %:");
JLabel statsDisplay = new JLabel("N/A");
JButton aceButton = new JButton("A");
JButton twoButton = new JButton("2");
JButton threeButton = new JButton("3");
JButton fourButton = new JButton("4");
JButton fiveButton = new JButton("5");
JButton sixButton = new JButton("6");
JButton sevenButton = new JButton("7");
JButton eightButton = new JButton("8");
JButton nineButton = new JButton("9");
JButton tenButton = new JButton("10");
JButton faceButton = new JButton("F");
JButton clearButton = new JButton("C");
JButton standButton = new JButton("Stand");
JButton hitButton = new JButton("Hit");
JButton doubleButton = new JButton("Double");
JButton splitButton = new JButton("Split");
JButton winButton = new JButton("Win");
JButton loseButton = new JButton("Lose");
JButton resetButton = new JButton("Reset All");
JButton enterButton = new JButton("Enter");
public Frame21()
{
// JFrame - the main area of the program
JFrame frame = new JFrame("Blackjack Helper");
// JPanel right - the rightside of the program
JPanel rightSide = new JPanel();
JPanel rightNorthSide = new JPanel();
rightNorthSide.setLayout(new GridLayout(3,4));
rightNorthSide.add(aceButton);
rightNorthSide.add(twoButton);
rightNorthSide.add(threeButton);
rightNorthSide.add(fourButton);
rightNorthSide.add(fiveButton);
rightNorthSide.add(sixButton);
rightNorthSide.add(sevenButton);
rightNorthSide.add(eightButton);
rightNorthSide.add(nineButton);
rightNorthSide.add(tenButton);
rightNorthSide.add(faceButton);
rightNorthSide.add(clearButton);
JPanel rightSouthSide = new JPanel();
rightSouthSide.add(resetButton, BorderLayout.WEST);
rightSouthSide.add(enterButton, BorderLayout.EAST);
rightSide.add(rightNorthSide, BorderLayout.NORTH);
rightSide.add(rightSouthSide, BorderLayout.SOUTH);
frame.add(rightSide, BorderLayout.EAST);
// JPanel Center - the center of the program
JPanel center = new JPanel();
JPanel centerNorth = new JPanel();
centerNorth.add(questionDisplay, BorderLayout.NORTH);
centerNorth.add(actionDisplay, BorderLayout.SOUTH);
JPanel centerSouth = new JPanel();
JPanel centerSouthNorth = new JPanel();
centerSouthNorth.add(dealerCardText, BorderLayout.WEST);
centerSouthNorth.add(dealerCardDisplay, BorderLayout.EAST);
JPanel centerSouthSouth = new JPanel();
JPanel centerSouthSouthWest = new JPanel();
centerSouthSouthWest.add(handOneText, BorderLayout.NORTH);
centerSouthSouthWest.add(handOneDisplay, BorderLayout.SOUTH);
JPanel centerSouthSouthEast = new JPanel();
centerSouthSouthEast.add(handTwoText, BorderLayout.NORTH);
centerSouthSouthEast.add(handTwoDisplay, BorderLayout.SOUTH);
centerSouthSouth.add(centerSouthSouthWest, BorderLayout.WEST);
centerSouthSouth.add(centerSouthSouthEast, BorderLayout.EAST);
centerSouth.add(centerSouthNorth, BorderLayout.NORTH);
centerSouth.add(centerSouthSouth, BorderLayout.SOUTH);
center.add(centerNorth, BorderLayout.NORTH);
center.add(centerSouth, BorderLayout.SOUTH);
frame.add(center, BorderLayout.CENTER);
// JPanel left - the center of the program
JPanel left = new JPanel();
JPanel leftNorth = new JPanel();
JPanel leftNorthNorth = new JPanel();
JPanel leftNorthSouth = new JPanel();
JPanel leftSouth = new JPanel();
JPanel leftSouthNorth = new JPanel();
JPanel leftSouthSouth = new JPanel();
leftNorthNorth.add(standButton, BorderLayout.WEST);
leftNorthNorth.add(hitButton, BorderLayout.EAST);
leftNorthSouth.add(doubleButton, BorderLayout.WEST);
leftNorthSouth.add(splitButton, BorderLayout.EAST);
leftNorth.add(leftNorthNorth, BorderLayout.NORTH);
leftNorth.add(leftNorthSouth, BorderLayout.SOUTH);
leftSouthNorth.add(statsText, BorderLayout.WEST);
leftSouthNorth.add(statsDisplay, BorderLayout.EAST);
leftSouthSouth.add(winButton, BorderLayout.WEST);
leftSouthSouth.add(loseButton, BorderLayout.EAST);
leftSouth.add(leftSouthNorth, BorderLayout.NORTH);
leftSouth.add(leftSouthSouth, BorderLayout.SOUTH);
left.add(leftNorth, BorderLayout.NORTH);
left.add(leftSouth, BorderLayout.SOUTH);
frame.add(left, BorderLayout.WEST);
frame.setSize(1600, 200);
frame.setVisible(true);
frame.setResizable(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}

The layering for what seems to be the upper layers is not working properly. Any suggestions? The left should have four layers.
A BorderLayout does not "layer".
Only a single component can be added to each of the 5 areas of the BorderLayout.
So, yes, you can create a JPanel and add multiple components to that panel, and then add the panel to an area of the BorderLayout.
JPanel rightSouthSide = new JPanel();
rightSouthSide.add(resetButton, BorderLayout.WEST);
rightSouthSide.add(enterButton, BorderLayout.EAST);
However, the above code is incorrect. The default layout manager of a JPanel is the FlowLayout. So specifying BorderLayout constraints does nothing (and is very confusing).
If by "layers" you mean "rows", then you need to use a panel with a different layout manage. Maybe you can use a BoxLayout to add rows of panels.
Overall, your approach to creating panels with different components is valid, the problem is you also need to use the appropriate layout manager for each of your child panels.
Read the Swing tutorial on Layout Managers for more information about how each of the layout managers work.

Using JPanel to make a calculator: how to use layout?

I'm working on a question that simply states to make an GUI that looks like This calculator, it doesn't have to function, just look like it. So I think I have the JPanel and JButton components right but I can't organize the fields to make it come out right. I'm pretty new so any crash course on how to organize a GUI would be appreciated.
Here's what I have so far:
// Using a JPanel to help lay out components.
import java.awt.GridLayout;
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JButton;
import javax.swing.JTextField;
public class Calculator extends JFrame
{
private final JPanel buttonJPanel2, buttonJPanel3, buttonJPanel4,
buttonJPanel5; // panel to hold buttons
private final JButton[] buttons3, buttons4, buttons5;
private final JButton[] buttons2;
private final JTextField buttonJPanel1;
// no-argument constructor
public Calculator()
{
super("Calculator");
buttonJPanel1 = new JTextField();
add(buttonJPanel1, BorderLayout.NORTH); // add panel1 to JFrame
buttons2 = new JButton[4];
buttons2[0] = new JButton("7");
buttons2[1] = new JButton("8");
buttons2[2] = new JButton("9");
buttons2[3] = new JButton("/");
buttonJPanel2 = new JPanel();
buttonJPanel2.setLayout(new GridLayout(1, buttons2.length));
add(buttonJPanel2, BorderLayout.AFTER_LAST_LINE); // add panel2 to JFrame
buttons3 = new JButton[4];
buttons3[0] = new JButton("4");
buttons3[1] = new JButton("5");
buttons3[2] = new JButton("6");
buttons3[3] = new JButton("*");
buttonJPanel3 = new JPanel();
buttonJPanel3.setLayout(new GridLayout(1, buttons3.length));
add(buttonJPanel3, BorderLayout.AFTER_LAST_LINE); // add panel3 to JFrame
buttons4 = new JButton[4];
buttons4[0] = new JButton("1");
buttons4[1] = new JButton("2");
buttons4[2] = new JButton("3");
buttons4[3] = new JButton("-");
buttonJPanel4 = new JPanel();
buttonJPanel4.setLayout(new GridLayout(1, buttons4.length));
add(buttonJPanel4, BorderLayout.AFTER_LAST_LINE); // add panel4 to JFrame
buttons5 = new JButton[4];
buttons2[0] = new JButton("0");
buttons5[1] = new JButton(".");
buttons5[2] = new JButton("=");
buttons5[3] = new JButton("+");
buttonJPanel5 = new JPanel();
buttonJPanel5.setLayout(new GridLayout(1, buttons5.length));
add(buttonJPanel5, BorderLayout.AFTER_LAST_LINE); // add panel5 to
//JFrame
}
public static void main(String[] args)
{
PanelFrame panelFrame = new PanelFrame();
panelFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panelFrame.setSize(700, 500);
panelFrame.setVisible(true);
}
} // end class PanelFrame

In short: every component has to be declared,
JButton button1;
initialized
button1 = new JButton("Click me!");
and added to the component above it in the hierarchy (in this case the panel)
panel1.add(button1);
If you do not add the components to the panel and the panel to the frame they will not be part of the GUI, thus not visible.
A JPanel can be set to adjust its layout in different ways using a LayoutManager as you have done with GridLayout (which seems fitting for a calculator). I suggest you read about how to use the grid layout here.
Hope I could help :)

You need to add the buttons to the `JPanel'. For example:
for(JButton b : buttons2) { buttonJPanel2.add(b); }
BorderLayout accepts one component at each location, so if you set BorderLayout.AFTER_LAST_LINE twice, the last add overwrites previous one.

setVgap(0), setHgap(0) not working in gridlayout?

I am trying to build an app that has some components such as buttons, labels, text fields, a menu bar and a picture (I didn't tackle the image problem yet so there is no code for that).
So I made a grid layout for my frame and constructed 6 panels with their respective components as explained in the code bellow. But when I run it it doesn't show anything at first, just a blank frame, unless I maximize the window. Because when I do that everything appears to be working fine. Except for 2 things.
I have setVgap() and setHgap() to zero but there are still gaps between the components. and the 2nd thing is that the BorderLayout.NORTH, (..).SOUTH etc don't seem to work either.
public class Window extends JFrame {
private static final long serialVersionUID = 1L;
private JPanel menupanel = new JPanel();
public Window() {
super("Image Application");
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
requestFocus();
// Setting Layout
GridLayout grid = new GridLayout(6, 0, 0, 0);
//grid.setVgap(0);
//grid.setHgap(0);
this.setLayout(grid);
// Menu
JMenuBar menubar = new JMenuBar();
JMenu menu = new JMenu("Options");
JButton button = new JButton("Reset");
// Buttons
menupanel.add(new JButton("Allign Left"));
menupanel.add(new JButton("Allign Center"));
menupanel.add(new JButton("Allign Right"));
// Picture
JPanel p1 = new JPanel();
// 2x JLabels and ComboBoxes to get the preferred dimensions
JPanel p2 = new JPanel();
JPanel p3 = new JPanel();
JLabel b2 = new JLabel("Width: ");
JLabel b3 = new JLabel("Height: ");
JTextField box1 = new JTextField(25);
JTextField box2 = new JTextField(25);
// Resize Button
JPanel p4 = new JPanel();
JButton b4 = new JButton("Resize");
// Adding Components to their panels
p2.add(b2);
p2.add(box1);
p3.add(b3);
p3.add(box2);
p4.add(b4);
menu.add(button);
menubar.add(menu);
// add all of the panels to JFrame
this.add(menupanel);
this.add(p1, BorderLayout.NORTH);
this.add(p2, BorderLayout.SOUTH);
this.add(p3, BorderLayout.WEST);
this.add(p4, BorderLayout.EAST);
this.setJMenuBar(menubar);
pack();
setVisible(true);
}
public static void main(String args[]) {
Window w = new Window();
}
}
Any ideas?
~EDIT1 changed according to first 2 comments, the pack(); seems to fix the problem that i needed to maximise the window to see the comp's ( -Thanks ), but the setVgap() problem remains.
~EDIT2 when I run it this window is shown:
While I want it to look more like this:
AGAIN Ignore the picture
~EDIT3 Well, I changed the value that was passed in the constructor for the Hgap and it does change accordingly for different values but it seems that zero Hgap is still ~10 pixels wide?! Also I noted that the gap doesn't change between the menubar and the first Jbuttons, but only for the ret of the components.
~EDIT4 It also works for negative int's..?! I am lost here..

please to compare, you should using second parameter for GridLayout, then setVgap() will works (frame.setLayout(new GridLayout(6, 0, 5, 5));), here is only zero value,
Window is reserved word in Java for awt.Window, don't to use this Object name as class name
import java.awt.Color;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class MyWindow {
private static final long serialVersionUID = 1L;
private JPanel menupanel = new JPanel();
private JFrame frame = new JFrame("Image Application");
public MyWindow() {
// Menu
JMenuBar menubar = new JMenuBar();
JMenu menu = new JMenu("Options");
JButton button = new JButton("Reset");
// Buttons
menupanel.add(new JButton("Allign Left"));
menupanel.add(new JButton("Allign Center"));
menupanel.add(new JButton("Allign Right"));
// Picture
JPanel p1 = new JPanel();
p1.setBackground(Color.RED);
// 2x JLabels and ComboBoxes to get the preferred dimensions
JPanel p2 = new JPanel();
p2.setBackground(Color.ORANGE);
JLabel b2 = new JLabel("Width: ");
p2.add(b2);
JTextField box1 = new JTextField(25);
p2.add(box1);
JPanel p3 = new JPanel();
p3.setBackground(Color.BLUE);
JLabel b3 = new JLabel("Height: ");
JTextField box2 = new JTextField(25);
p3.add(b3);
p3.add(box2);
// Resize Button
JPanel p4 = new JPanel();
p4.setBackground(Color.MAGENTA);
JButton b4 = new JButton("Resize");
// Adding Components to their panels
p4.add(b4);
menu.add(button);
menubar.add(menu);
// add all of the panels to JFrame
frame.setLayout(new GridLayout(6, 0, 5, 5));
frame.add(menupanel);
frame.add(p1);
frame.add(p2);
frame.add(p3);
frame.add(p4);
frame.setJMenuBar(menubar);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
MyWindow w = new MyWindow();
}
});
}
}

Vertical alignement in Java Swing

How can I make buttons like this?
JPanel jp = new JPanel();
JPanel jpB1 = new JPanel();
JPanel jpB2 = new JPanel();
JPanel jpB3 = new JPanel();
JButton jb1 = new JButton("button1");
JButton jb2 = new JButton("button2");
JButton jb3 = new JButton("button3");
...
JLabel jl = new JLabel("label");
...
jp.setLayout(new BorderLayout());
...
jpB1.add(jb1);
jpB2.add(jb2);
jpB3.add(jb3);
...
jp.add(jpB1, BorderLayout.NORTH);
jp.add(jpB2, BorderLayout.CENTER);
jp.add(jpB3, BorderLayout.SOUTH);
...
I tried this code on creating 3 panels and add them to the main panel. It shows two buttons on north and one button on south! Can someone help me?

Note, the default layout of JPanel is FlowLayout; a GridBagLayout with default constraints is centered in the frame's BorderLayout.CENTER. Also, pack() the enclosing Window and display it last. Using Initial Threads left as an exercise.
Addendum: A useful trick for solving layout problems is setting the background color of an enclosing container to a contrasting color, for example
jpB2.setBackground(Color.blue);
import java.awt.BorderLayout;
import java.awt.GridBagLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Bouton2 {
public static void main(String[] args) {
final int LARGEUR = 400;
final int HAUTEUR = 300;
JFrame jf = new JFrame();
JPanel jp = new JPanel();
JPanel jpB1 = new JPanel();
JPanel jpB2 = new JPanel(new GridBagLayout());
JPanel jpB3 = new JPanel();
JButton jb1 = new JButton("Cliquez ici");
JButton jb2 = new JButton("Je compte");
JButton jb3 = new JButton("J'agrandis");
JLabel jl = new JLabel("0 clic");
jp.setLayout(new BorderLayout());
jpB1.add(jb1);
jpB2.add(jb2);
jpB3.add(jb3);
jp.add(jpB1, BorderLayout.NORTH);
jp.add(jpB2, BorderLayout.CENTER);
jp.add(jpB3, BorderLayout.SOUTH);
jf.setTitle("Fenêtre Bouton2");
jf.setContentPane(jp);
jf.pack();
jf.setSize(LARGEUR, HAUTEUR);
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jf.setLocationRelativeTo(null);
jf.setVisible(true);
}
}