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Problems with BorderLayout() in Java

I've tried a lot of different ways, but I will explain two and what was happening (no error messages or anything, just not showing up like they should or just not showing up at all):
First, I created a JPanel called layout and set it as a BorderLayout. Here is a snippet of how I made it look:
JPanel layout = new JPanel();
layout.setLayout(new BorderLayout());
colorChoice = new JLabel("Choose your color: ");
layout.add(colorChoice, BorderLayout.NORTH);
colorBox = new JComboBox(fireworkColors);
colorBox.addActionListener(this);
layout.add(colorBox, BorderLayout.NORTH);
In this scenario what happens is they don't show up at all. It just continues on with whatever else I added.
So then I just tried setLayout(new BorderLayout()); Here is a snippet of that code:
setLayout(new BorderLayout());
colorChoice = new JLabel("Choose your color: ");
add(colorChoice, BorderLayout.NORTH);
colorBox = new JComboBox(fireworkColors);
colorBox.addActionListener(this);
add(colorBox, BorderLayout.NORTH);
In this scenario they are added, however, the width takes up the entire width of the frame and the textfield (not shown in the snippet) takes up basically everything else.
Here is what I have tried:
setPreferredSize() & setSize()
Is there something else that I am missing? Thank you.
I also should note that this is a separate class and there is no main in this class. I only say this because I've extended JPanel instead of JFrame. I've seen some people extend JFrame and use JFrame, but I haven't tried it yet.

You created a JPanel, but didn't add it to any container. It won't be visible until it is added to something (a JFrame, or another panel that is in a frame somewhere up the hierarhcy)
You added two components to the same position in the BorderLayout. The last one added is the one that will occupy that position.
Update:
You do not need to extend JFrame. I never do, instead I always extend JPanel. This makes my custom components more flexible: they can be added in another panel, or they can be added to a frame.
So, to demonstrate the problem I will make an entire, small, program:
public class BadGui
{
public static void main(String[] argv)
{
final JFrame frame = new JFrame("Hello World");
final JPanel panel = new JPanel();
panel.add(new JLabel("Hello"), BorderLayout.NORTH);
panel.add(new JLabel("World"), BorderLayout.SOUTH);
frame.setVisible(true);
}
}
In this program I created a panel, but did not add it to anything so it never becomes visible.
In the next program I will fix it by adding the panel to the frame.
public class FixedGui
{
public static void main(String[] argv)
{
final JFrame frame = new JFrame("Hello World");
final JPanel panel = new JPanel();
panel.add(new JLabel("Hello"), BorderLayout.NORTH);
panel.add(new JLabel("World"), BorderLayout.SOUTH);
frame.getContentPane().add(panel);
frame.setVisible(true);
}
}
Note that in both of these, when I added something to the panel, I chose different layout parameters (one label I put in 'North' and the other in 'South').

Here is an example of a JPanel with a BorderLayout that adds a JPanel with a button and label to the "North"
public class Frames extends JFrame
{
public Frames()
{
JPanel homePanel = new JPanel(new BorderLayout());
JPanel northContainerPanel = new JPanel(new FlowLayout());
JButton yourBtn = new JButton("I Do Nothing");
JLabel yourLabel = new JLabel("I Say Stuff");
homePanel.add(northContainerPanel, BorderLayout.NORTH);
northContainerPanel.add(yourBtn);
northContainerPanel.add(yourLabel);
add(homePanel);
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setLocationRelativeTo(null);
setExtendedState(JFrame.MAXIMIZED_BOTH);
setTitle("Cool Stuff");
pack();
setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(Frames::new);
}
}

The below suggestion is assuming that your extending JFrame.
Testing
First of all, without seeing everything, theres always a numerous amount of things you can try.
First off, after you load everything, try adding this in (Again, assuming your extending JFrame:
revalidate();
repaint();
I add this into my own Swing projects all the time, as it refreshes and checks to see that everything is on the frame.
If that doesn't work, make sure that all your JComponent's are added to your JPanel, and ONLY your JPanel is on your JFrame. Your JFrame cannot sort everything out; the JPanel does that.
JPanel window = new JPanel();
JButton button = new JButton("Press me");
add(window);
window.add(button); // Notice how it's the JPanel that holds my components.
One thing though, you still add your JMenu's and what-not through your JFrame, not your JPanel.

Trying to add a JLabel, but it is stuck in the middle of Jframe

I am trying to add a JLabel but the problem is that it is eith stuck in the middle or to the left of the jframe.
Here is my code;
public class test extends JFrame{
public test(){
JLabel text = new JLabel("test")
text.setLocation(100,100);
setTitle("Help me");
setSize(500,500);
add(text);
}
}
public class Runner{
public static void main (String[] args){
test a = new test();
}
}

Every container has a layout manager that set the position and size of the elements it contains according to its own rules. JFrame default layout is BorderLayout, which put things by default on the left.
To position components absolutely, you have to set the layout manager to null and explicitely call repaint() on your JFrame every time you add/remove/modify your components. You also have to set the size of the components, not only their position (use for example setBounds to set them all in one call.
As an example, The following code does what you want:
public class Test extends JFrame {
public Test() {
// remove any layout manager.
setLayout(null);
setTitle("Help me");
setSize(500, 500);
JLabel text = new JLabel("test");
// set size and position of component.
text.setBounds(new Rectangle(100, 100, 200, 200));
// add component.
add(text);
// explicitely call repaint().
repaint();
}
public static void main(String[] args) {
new Test().setVisible(true);
}
}
For more informations, you can look at the Oracle tutorial on working without a layout manager.
Edit: I would still advise you to use normal layout managers to achieve what you want, as positioning everything absolutely is usually a pain.

add(text);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);

Java GUI JScrollPane

I am a beginer at programing and i wanted to add a scroll panel to a JTextArea so i tried to research tutorials online. i followed the examples but its not working can someone plz tell me what i am doing wrong. thank you so much
public View(Model model) {
this.model = model;
setBounds(100,50, 800, 400);
setDefaultCloseOperation(EXIT_ON_CLOSE);
Container c = getContentPane();
addDisplay(c);
addButtons(c);
addTxt(c);
}
private void addDisplay(Container c){
JPanel p = new JPanel();
addTxt2(p);
addTxt(p);
add(p, "North");
}
private void addTxt(JPanel p){
txt = new JTextArea(15, 35);
txt.setBackground(Color.BLACK);
txt.setForeground(Color.WHITE);
txt.setEditable(true);
JScrollPane scroll= new JScrollPane (txt);
p.add(scroll);
}

Always invoke revalidate and repaint after adding any components to a JPanel
p.add(scroll);
p.revalidate();
p.repaint();
From the use of setBounds, it appears that there is no layout manager in use. Don't use absolute positioning (null layout). By default, components have a size of 0 x 0 so will not appear unless their size is set. A layout manager should be used here instead.
Post an SSCCE for better help sooner

You have to set the bounds of your scroll setBounds(int, int, int, int)
and define the area of your JTextArea
Here's an example:
public class ScrollingTextArea extends JFrame {
JTextArea txt = new JTextArea();
JScrollPane scrolltxt = new JScrollPane(txt);
public ScrollingTextArea() {
setLayout(null);
scrolltxt.setBounds(3, 3, 300, 200);
add(scrolltxt);
}
public static void main(String[] args) {
ScrollingTextArea sta = new ScrollingTextArea();
sta.setSize(313,233);
sta.setTitle("Scrolling JTextArea with JScrollPane");
sta.show();
}
}
I've found it here

placing a transparent JPanel on top of another JPanel not working

I am trying to place a JPanel on top of another JPanel which contains a JTextArea and a button and i want to the upper apnel to be transparent. I have tried it by making the setOpaque(false) of the upper panel. but it is not working. Can anyone help me to get through this? Thanks in advance!
public class JpanelTest extends JPanel
{
public JpanelTest()
{
super();
onInit();
}
private void onInit()
{
setLayout(new BorderLayout());
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
panel.add(new JTextArea(100,100),BorderLayout.CENTER);
panel.add(new JButton("submit"),BorderLayout.SOUTH);
JPanel glass = new JPanel();
glass.setOpaque(false);
add(panel,BorderLayout.CENTER);
add(glass,BorderLayout.CENTER);
setVisible(true);
}
public static void main(String args[])
{
new JpanelTest();
}
}

Indeed, it would be useful to tell the reason why you want panels one over another.
Starting with your code, and changing it a lot, I got it to work, but it might not do what you expect...
import java.awt.*;
import javax.swing.*;
public class Test extends JFrame
{
public Test()
{
super();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(500, 200);
onInit();
setVisible(true);
}
private void onInit()
{
JLayeredPane lp = getLayeredPane();
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
panel.add(new JTextArea(), BorderLayout.CENTER);
panel.add(new JButton("Submit"), BorderLayout.SOUTH);
panel.setSize(300, 150); // Size is needed here, as there is no layout in lp
JPanel glass = new JPanel();
glass.setOpaque(false); // Set to true to see it
glass.setBackground(Color.GREEN);
glass.setSize(300, 150);
glass.setLocation(10, 10);
lp.add(panel, Integer.valueOf(1));
lp.add(glass, Integer.valueOf(2));
}
public static void main(String args[])
{
// Schedule a job for the event-dispatching thread:
// creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new Test();
}
});
}
}
If totally transparent, well, it is like it isn't here! When opaque, it just covers some of the GUI, but doesn't prevent mouse clicks, for example.

1) there are a few ways, there no issue to put JPanel, with covering full JFrames/JPanel area or only part of Rectangle / Dimension that returns JFrames/JPanel
use JLayer(Java7) based on JXLayer (Java6)
use GlassPane
use JViewport
use OverlayLayout
use transucent JDialog / JWindow
2) everything depends of if you want to protect against mouse and key events from the top layer to bottom, or not (to avoiding redispatch events from - to and vice versa)

Check out this tutorial on using Swing Root Panes.
The glass pane is useful when you want to be able to catch events or paint over an area that already contains one or more components. For example, you can deactivate mouse events for a multi-component region by having the glass pane intercept the events. Or you can display an image over multiple components using the glass pane.

How can I force a JFrame to have a certain amount of space for a component?

public class n00767255 {
public static void main(String[] args) {
CarFrame frame = new CarFrame();
frame.setSize(600,480);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
while(true)
{
frame.repaint();
}
}
}
class CarFrame extends JFrame {
CarFrame() {
setLayout(new GridLayout(3,1));
final CarPanel car1 = new CarPanel();
car1.initCar(10,50,2,150,70,40);
add(car1);
final CarPanel car2 = new CarPanel();
car2.initCar(10,50,2,150,70,40);
add(car2);
JButton startCar1 = new JButton("Start Car 1");
JPanel panel = new JPanel();
panel.setSize(600,40);
panel.add(startCar1);
add(panel);
startCar1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if(!car1.getMovingF())
{
car1.modifyMovingF();
}
}
});
}
}
What I want this to do is to create the two CarPanels with the basic car shape and for those both to by 600X200 and be spaced properly so the full objects can be seen. Under that I want to paste the panel with a bunch of different buttons that do different things. Here my problem is that the cars never have enough space to be seen entirely, and using different layout managers hasn't helped.
EDIT
After numerous changed this code is not working at all the way I would expect. At this point the first car is the only one shown and the start car button is at the top of the frame.

Have a look at frame.pack: http://docs.oracle.com/javase/6/docs/api/java/awt/Window.html#pack%28%29 - It sets the size of a window so that it fits the preferred size of its contents.
If the content of the frame has a correclty set preferred size, just call
frame.pack();
instead of
frame.setSize(600,480);
in your application - that should do the trick.
Edit: Another problem with your code is that you probably use the wrong layout manager. GridLayout creates a regular grid, this means all cells have the same size. You should try a layout that supports a more flexible sizing of cells, like JGoodies FormLayout or MigLayout.
I have tried your code with the following CarPanel implementation, GridLayout seems to ignore the sizes of it's children:
private class CarPanel extends JPanel {
public CarPanel() {
setBorder(BorderFactory.createLineBorder(Color.BLACK));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(600, 20);
}
}
http://www.miglayout.com/
http://www.jgoodies.com/freeware/libraries/forms/

Try using JFrame's pack method.
public static void main(String[] args) {
CarFrame frame = new CarFrame();
frame.setPreferredSize(new Dimension(600,480));
frame.setLocationRelativeTo(null);
frame.pack();
//...rest of code
}
}

See the API for methods like setSize setMinimumSize setMaximumSize and setPreferredSize