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Why doesn't my button position properly on my JFrame no layout?

So I've got a JFrame which uses setLayout(null) so I can position my elements by hand.
However, when accessing the content pane and getting the size for the frame, it says its height is 1.0.
Does anyone know how I can fix this?
Here is the code:
import javax.swing.*;
import java.awt.*;
public class Launcher extends JFrame
{
public Launcher(String title) {
super(title);
setLayout(null);
pack();
setSize(new Dimension(LauncherUtil.LAUNCHER_WIDTH, LauncherUtil.LAUNCHER_HEIGHT));
setLocationRelativeTo(null);
setResizable(false);
setDefaultCloseOperation(EXIT_ON_CLOSE);
displayComponents();
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
Launcher launch = new Launcher(LauncherUtil.LAUNCHER_TITLE);
launch.setVisible(true);
}
});
}
private void displayComponents() {
Dimension size = getContentPane().getSize();
JButton launchButton = new JButton("Launch Game");
System.out.println(size.getHeight());
launchButton.setBounds(0, (int)size.getHeight() - 60, (int)size.getWidth(), 60);
add(launchButton);
}
}

may be if you try to get the screen size by using Toolkit would be work like you want
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
it brings you the screen size where java program is running. Hope it helps.

The content pane is a JPanel whose default size is 1x1px. Since you did not put any components into the content pane and have not set a preferred size for the panel, the content pane's size remains 1x1px.
One way to fix this is to call these three methods in the following order:
setLayout(null);
setPreferredSize(new Dimension(300, 400));
pack();
However, you should be using a layout manager instead of managing
the size and position of your components by hand.

How can I place a JLabel on a specific position within a JFrame?

We're about to create an online based Space Invaders-game with implemented graphics. I've been reading about JFrames, JPanels and JLabels in order to create a window with a grid where the ships and monsters will be placed in.
So, here's the thing, I've been looking through the different layouts that exists, but nothing really seems to fit our purpose. I would like a simple JFrame with the possibility of placing JLabel-objects on a certain position (with setBounds(), setLocation() or something similar). This requires setLayout(null) which I've heard isn't a good solution? I was thinking of having objects in a fixed 30x30px size, and a fixed window size of 600x600px (giving me a grid of 20*20).
Anyhow, I've been trying to get it to work with setLayout(null), but without any results. If I apply a layout, say FlowLayout, the ship is visible, but stuck in either LEFT, CENTER or MIDDLE.
public class GUI extends JFrame {
JPanel p = new JPanel(null);
public GUI() {
try{
this.setContentPane(new JLabel(new ImageIcon(ImageIO.read(new File("graphics/bg.png")))));
}catch(IOException e) {
System.out.println("Image does not exist");
}
this.setLayout(null);
this.setResizable(false);
this.setSize(600,600);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setVisible(true);
}
public void placeShip1() {
ImageIcon ship2 = new ImageIcon("graphics/ship2.png");
JLabel imageLabel = new JLabel(ship2);
imageLabel.setBounds(200,200,30,30);
p.add(imageLabel);
p.setOpaque(false);
p.setSize(600, 600);
this.add(p);
this.setVisible(true);
}
}
I really can't see why it doesn't work. I mean, all I want is my JFrame with a background image and with an object on a certain position, but instead the object doesn't show at all.
The main reason for wanting to use setLayout(null) is because I was thinking of using a method translating our grid coordinates to the JFrame, simply mapping each coordinate to respective cell.

How to adjust parent container size by the child container?

More specifically, how to adjust JFrame size by its contentPane.
Here is the case, I am doing a 400*400 JPanel and I need it to fit in the JFrame. However if I set JFrame setSize(400, 400), some part of the JPanel would be hid due to the space occupied by the upper windows title bar.
I know I can just measure the border and the size of the title bar. I just want to know if there is better way to do.
Here is the solution that takes both Hovercraft Full Of Eels and MadProgrammer answer.
public class Window extends JFrame {
private Window() {
createUI();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Window();
}
});
}
private void createUI() {
setContentPane(buildMainPanel());
pack();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
}
private JPanel buildMainPanel() {
JPanel mainPanel = new JPanel();
mainPanel.setPreferredSize(new Dimension(500, 640));
mainPanel.setLayout(null);
mainPanel.add(new Canvas(0, 0));
return mainPanel;
}
}

However if I set JFrame setSize(400, 400), some part of the JPanel would be hid due to the space occupied by the upper windows title bar.
You're making things too hard for yourself since the easiest solution is to simply not set the JFrame size. Instead call pack() on the JFrame after adding all components and before calling setVisible(true) and let it size itself to the optimum size for its components and layout managers.

Override the panel's getPreferredSize method and return new Dimension(400, 400).
On the frame call pack. When called, pack will ask the content pane for it's preferred size, which is normally calculated by the layout manager (recursively ask each container for it's preferred size).
This will size the window so that's viewable area meets (as much as its possible to do so) the preferred size of it's content.

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);

How can I make my GUI Frame larger?

The problem is, I am unable to make it a dimension with 800x600. In other words, when I run the program, the frame is so small that I can not do anything with it.
How can I make the frame larger?
I have set the preferred size already ans set the canvas bounds.
Then what is the problem?
public class GameCanvas extends Canvas
{
private BufferStrategy buffer = null;
public GameCanvas()
{
setBounds(0, 0, 800, 600);
setIgnoreRepaint(true);
addKeyListener(new KeyInputHandler());
requestFocus();
}
public void addNotify()
{
super.addNotify();
this.createBufferStrategy(2);
buffer = this.getBufferStrategy();
setBounds(0, 0, 800, 600);
}
}
public class GameGuiFrame extends JFrame
{
private JPanel panel = new JPanel();
private GameCanvas canvas = new GameCanvas();
public GameGuiFrame()
{
this.setName("My Game");
this.pack();
this.setResizable(false);
this.setVisible(true);
panel = (JPanel) this.getContentPane();
panel.setPreferredSize(new Dimension(750,500));
panel.setLayout(null);
panel.add(canvas);
}
}
public class GameManager
{
public static void runGameLoop()
{
GameGuiFrame container = new GameGuiFrame();
container.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
}
public class Main
{
public static void main(String [] args)
{
GameManager.runGameLoop();
}
}

Try packing the Frame after you set the preferred size of the content pane.

Not related to your question but based on the code you posted it looks like you've copied some old AWT code and are trying to use it in a Swing application.
I would suggest you only use Swing components. There is no need to use a Canvas with a BufferStrategy. Just use a JPanel it is double buffered by default. The code snippet you copied is old and that is not the way it is done in Swing.
Don't use a null layout. Swing was designed to be using with layout managers. Then the pack() method will be able to do its job properly.
There is no need to use a WindowListener to close the frame. These days people just use:
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Also, the frame should be made visible AFTER components have been added to the frame.
Generally you should be use Key Bindings, not a KeyListener to listen for key events in a Swing application.
I suggest you look at the Swing tutorial for more information about the above concepts.

You call to pack() will set the frame (and components within it) to their preferred size. However, you haven't specified a preferred size. I would suggest removing your two calls to setBounds() and calling setBounds() within the main method instead of pack().