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Adding two JComponents to the North of a JFrame BorderLayout

I have a paint-like project, in which I recently added a JSpinner, but after researching how to add it to the JFrame, it ends up looking like this:
but I would like it to look like this:
how would I accomplish this? Thanks in advance.
P.D: The code used to create the current project is this:
public View( final String title ){
super( title );
}
public void init()
{
canvas = new Canvas();
menuManager = new MenuManager();
toolBarManager = new ToolBarManager( JToolBar.VERTICAL );
spinnerManager = new SpinnerManager();
JPanel subPanel = new JPanel( new FlowLayout() );
subPanel.add( menuManager );
subPanel.add( spinnerManager );
add( BorderLayout.CENTER, canvas );
add( BorderLayout.NORTH, menuManager);
add( BorderLayout.EAST, toolBarManager );
setDefaultCloseOperation( EXIT_ON_CLOSE );
App.getInstance().addDrawingListener( this );
canvas.init();
}

Simply give the top JPanel an appropriate FlowLayout: new FlowLayout(FlowLayout.LEADING))

GridLayout with component fixed Width and Height?

I have a main Panel and I'm adding components dynamically into that one.
Main Panel has GridLayout limited to 3 columns and 0 rows (0 rows will allow rows to grow infinitely), but the problem is that I want all components to have fixed size or component's preferred size.
I can use other layout if it meets my requirements... but for now only GridLayout allows me to limit columns to 3...
I forgot to mention, Main Panel is added into JScrollpane, so I can scroll vertically.

One way to to do this is to use JPanels. GridLayout will stretch your components, but if you wrap the component in a JPanel, then the JPanel gets stretched. And since JPanel uses FlowLayout, which does not stretch components, your components remain at their preferred size.
Here's an example using JButton. Notice how I add them to a (new) JPanel each loop, then I add the panel to the grid layout.
import javax.swing.*;
public class GridLayout {
public static void main( String[] args ) {
SwingUtilities.invokeLater( new Runnable() {
public void run() {
JFrame frame = new JFrame();
frame.setLayout( new java.awt.GridLayout( 0, 3 ) );
for( int i = 0; i < 21; i++ ) {
JPanel panel = new JPanel(); // Make a new panel
JButton button = new JButton( "Button "+i );
panel.add( button ); // add the button to the panel...
frame.add( panel ); // ...then add the panel to the layout
}
frame.pack();
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.setLocationRelativeTo( null );
frame.setVisible( true );
}
} );
}
}

Massive space between components

Please have a look at the following code
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class GridLayoutTest2
{
private final JDialog msgDisplayer;
public GridLayoutTest2()
{
JLabel maleLabel = new JLabel("Male",JLabel.CENTER);
maleLabel.setBorder(BorderFactory.createEmptyBorder());
JLabel femaleLabel = new JLabel("Female",JLabel.CENTER);
femaleLabel.setBorder(BorderFactory.createEmptyBorder());
JLabel fmaleIcon = new JLabel();
fmaleIcon.setIcon(new ImageIcon(getClass().getResource("/images/TESTING-Image.gif")));
fmaleIcon.setBorder(BorderFactory.createEmptyBorder());
JLabel maleIcon = new JLabel();
maleIcon.setIcon(new ImageIcon(getClass().getResource("/images/TESTING-Image.gif")));
maleIcon.setBorder(BorderFactory.createEmptyBorder());
msgDisplayer = new JDialog();
msgDisplayer.setLayout(new GridLayout(4,1,1,1));
msgDisplayer.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
msgDisplayer.setTitle("Body Fat Percentage Classification");
msgDisplayer.add(femaleLabel);
msgDisplayer.add(fmaleIcon);
msgDisplayer.add(maleLabel);
msgDisplayer.add(maleIcon);
msgDisplayer.pack();
msgDisplayer.setVisible(true);
msgDisplayer.setLocationRelativeTo(null);
}
public static void main(String[]args)
{
try
{
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
new GridLayoutTest2();
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
This code contains a HUGE gap (space) between the labels and images screenshot attached). I do not want to have this space between labels and images. How can I eliminate it? I know I can go with the GridBagLayout to do it, but, is there any way in GridLayout? Please help!

GridLayout allocates an equals amount of space for all components based on the largest component in the container. If you don't wish to use a complex layout manager such as GridBagLayout, you could use BoxLayout, which uses the component's preferred sizes. A BoxLayout with Y_AXIS alignment would be suitable here.
Example

Thats not the gap space, its real size of JLabel's (maleLabel, fmaleLabel). Size of image determines size of parent JLabel and in GridLayout, all components will take size of largest component. Gap between components is 1 as you defined when setting layout. So solution of your problem lays in finding suitable layout manager.
Reimeus gave you an example of GridBagLayout and BoxLayout, and I would like to recommend you MiGLayout which is quite easy to use.

Its the Layout what matters!!
Here I have done a short EG with my GUI builder to show the adjustment of white space(or the size of JLabel):
More white space:
Code:
public class udyfash extends javax.swing.JFrame {
public udyfash() {
initComponents();
}
#SuppressWarnings("unchecked")
private void initComponents() {
jLabel1 = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jLabel1.setIcon(new javax.swing.ImageIcon(getClass().getResource("/images.jpg"))); // NOI18N
jLabel1.setText("yooo!!");
jLabel1.setBorder(javax.swing.BorderFactory.createCompoundBorder(null, javax.swing.BorderFactory.createLineBorder(new java.awt.Color(0, 0, 0))));
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, 405, Short.MAX_VALUE)
.addContainerGap())
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(44, 44, 44)
.addComponent(jLabel1)
.addContainerGap(39, Short.MAX_VALUE))
);
pack();
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new udyfash().setVisible(true);
}
});
}
private javax.swing.JLabel jLabel1;
}
We say GridBag is complex,but use the Layout Manager you are ok with.

How to Dynamically Add JButton to JPanel?

In NetBeans, I have used the GUI editor to make a JFrame and I've put a JPanel in the frame.
At the moment, I'm trying to make a new button in the panel when the class constructs.
This is the code I have, but I can't seem to get it to work.
(The first line makes the button, the other lines try to show it.)
this.jPanel2.add(new JButton("Test"),BorderLayout.NORTH);
this.jPanel2.validate();
this.jPanel2.revalidate();
this.jPanel2.repaint();
this.jPanel2.setVisible(true);
this.revalidate();
this.setVisible(true);
this.repaint();
I've been googling all night, but can't seem to get it to work.

Some times when you don't see a button it is a layout manager issue (as in you aren't setting the right properties for the layout manager). You can test this by disabling it:
this.jPanel2.setLayoutManager(null);
And setting bounds for the button (JButton.setBounds()).
If the above fixes your problem, then you need to look into the requirements set by the LayoutManager you are using (see also the answer by Robin).
All the calls to validate(), revalidate() and repaint() are not needed to do this.

Normally the add call is sufficient.
Note: a BorderLayout can only contain one component in each location. So if you add another component in the NORTH location, your button will not be visible.
Second note: by default a JPanel does not have a BorderLayout but a FlowLayout. Have you set a BorderLayout on that specific panel ? Otherwise the BorderLayout#NORTH constraint is incorrect
All the validate,revalidate,repaint calls can be removed
Edit
It seems some sort of validation is needed after all. I was under the impression that Swing should be smart enough to listen for the event when something is added to a Container, and update whatever is necessary (a bit similar to updating a TableModel updates the JTable based on events, without the need to call repaint or the likes on the JTable).
However, when trying this in an SSCCE, I came to the following code (different versions, only post the most elaborate version)
without the scroll-pane, the validate calls seem to have no effect. I actually need to call pack again to make the new labels visible (not included in the SSCCE, but removing the scrollpane from the code is trivial)
with the scroll-pane, the validate call has an effect
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class AddLabelsAtRuntime {
private int fLabelCounter = 0;
private JPanel fLabelPanel;
private final JFrame fTestFrame;
public AddLabelsAtRuntime() {
fLabelPanel = new JPanel( );
BoxLayout boxLayout = new BoxLayout( fLabelPanel, BoxLayout.PAGE_AXIS );
fLabelPanel.setLayout( boxLayout );
fTestFrame = new JFrame( "Dynamically add labels" );
}
private JFrame createUI(){
Container contentPane = fTestFrame.getContentPane();
contentPane.setLayout( new BorderLayout() );
JScrollPane scrollPane = new JScrollPane( fLabelPanel );
scrollPane.setPreferredSize( new Dimension( 200, 200 ) );
contentPane.add( scrollPane, BorderLayout.CENTER );
contentPane.add( createButtonPanel(), BorderLayout.SOUTH );
fTestFrame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
fTestFrame.pack();
return fTestFrame;
}
private void addLabel(){
fLabelPanel.add( new JLabel( "Label " + ++fLabelCounter ) );
}
private JPanel createButtonPanel(){
JPanel buttonPanel = new JPanel( );
BoxLayout boxLayout = new BoxLayout( buttonPanel, BoxLayout.LINE_AXIS );
buttonPanel.setLayout( boxLayout );
JButton validateButton = new JButton( "Add + validate" );
validateButton.addActionListener( new ActionListener() {
#Override
public void actionPerformed( ActionEvent e ) {
addLabel();
fLabelPanel.validate();
fTestFrame.validate();
}
} );
buttonPanel.add( validateButton );
JButton noValidateButton = new JButton( "Add" );
noValidateButton.addActionListener( new ActionListener() {
#Override
public void actionPerformed( ActionEvent e ) {
addLabel();
}
} );
buttonPanel.add( noValidateButton );
JButton packButton = new JButton( "Add + pack" );
packButton.addActionListener( new ActionListener() {
#Override
public void actionPerformed( ActionEvent e ) {
addLabel();
fTestFrame.pack();
}
} );
buttonPanel.add( packButton );
return buttonPanel;
}
public static void main( String[] args ) {
EventQueue.invokeLater( new Runnable() {
#Override
public void run() {
AddLabelsAtRuntime addLabelsAtRuntime = new AddLabelsAtRuntime();
addLabelsAtRuntime.createUI().setVisible( true );
}
} );
}
}

Create Dynamic JButton with Image and ActionListener - Java Swing
Create JButton dynamically with Image and the ActionListener . You will be able to change the button height , width horizontal gap and vertical gap in one place.
you can find more details from here

adding JLayeredPane to JPanel

I am trying to add a JLayeredPane to a JPanel and then add an image (JLabel icon) and a button to the JLayeredPane, but neither show up. I've tested the image without the button and the layeredpane so I know that works. Here is some of the code I am using. Is there something I am missing or doing wrong?
public class MyClass extends JPanel
{
private JLayeredPane layeredPane;
private JLabel imageContainer = new JLabel();
private JButton info = new JButton("i");
MyClass(ImageIcon image)
{
super();
this.imageContainer.setIcon(image);
this.layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(new Dimension(300, 300));
layeredPane.add(imageContainer, new Integer(50));
layeredPane.add(info, new Integer(100));
this.add(layeredPane);
}
}

From the tutorial
By default a layered pane has no layout manager. This means that you typically have to write the code that positions and sizes the components you put in a layered pane.
See the changes to your code:
import java.awt.*;
import javax.swing.*;
public class MyClass extends JPanel {
private JLayeredPane layeredPane;
private JLabel imageContainer = new JLabel();
private JButton info = new JButton("i");
MyClass(ImageIcon image) {
super();
this.imageContainer.setIcon(image);
this.layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(new Dimension(300, 300));
layeredPane.add(imageContainer, new Integer(50));
layeredPane.add(info, new Integer(100));
this.add(layeredPane);
// CHANGED CODE
// Manually set layout the components.
imageContainer.setBounds( 0, 0,
image.getIconWidth(),
image.getIconHeight() );
info.setBounds( 200, 00, 50, 40 );
}
public static void main( String [] args ) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.add( new MyClass( new ImageIcon("logo.png") ) );
frame.pack();
frame.setVisible( true );
}
}
Additional notes:
1) It is better ( in my opinion ) to put the opening brace in the same line. That's how most Java code looks like.
2) Avoid inheriting from JPanel ( or any other component ) if you don't are not really creating a subclass. You can use it directly without having to inherit ( unless you're indeed creating a new component.

JLayeredPane has a null layout manager by default, so in your example you'll need to set the location and size of the child components. You can set a layout manager on the JLayeredPane, but that will most likely negate the layered rendering I'm guessing you want, since you're using a layered pane.