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Creating a board game layout using JLayeredPane

I have an assignment which requires me to create the layout that you see in the image as part of the development of a game. I've never worked with Java for desktop applications before so i'm a complete noob when it comes to using the Swing & AWT libraries. The image suggests that we use a JLayeredPane as our root container and then add the rest on top of it. My issue is that i've tried starting with the background image and the gridLayout but i can't seem to make anything other than the background show up. The grid doesn't show up at all (no border line, no background of the cells) and any other component i've added to it has failed. Can somebody point me in the right direction here? I've read the docs & saw some example of various layouts,containers and components but i can't seem to make all of them work together.
Here's my code so far:
public class BoardView extends JFrame{
// Constructor
public BoardView() {
JFrame window = new JFrame("Sorry Game"); // create a new Jwindow instance
ImageIcon appIcon = new ImageIcon(getClass().getClassLoader().getResource("res/icon.png")); // create the icon for the app
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // when the 'X' button is clicked, the app stops
window.setSize(new Dimension(1000, 700)); // setting the size of the window
window.setResizable(false); // Window won't be resizable
window.setIconImage(appIcon.getImage()); // set the icon for the app
window.setLayout(new BorderLayout());
JLayeredPane layeredPane = new JLayeredPane();
JLabel background = new JLabel();
background.setSize(1000,700);
background.setIcon(new ImageIcon(getClass().getClassLoader().getResource("res/background.png"))); for the JLabel
layeredPane.add(background,0);
JPanel gridPanel = new JPanel(new GridLayout(16,16));
gridPanel.setSize(650,700);
layeredPane.add(gridPanel);
for(int i = 0; i < 256; i++) {
JLabel tile = new JLabel();
tile.setBackground(Color.red);
tile.setBorder(new LineBorder(Color.black));
gridPanel.add(tile);
}
JLabel logo = new JLabel();
logo.setIcon(new ImageIcon(getClass().getClassLoader().getResource("res/sorryImage.png")));
layeredPane.add(logo);
window.add(layeredPane);
window.setLocationRelativeTo(null); // centers the window to the screen
window.setVisible(true); // make the window visible
}
}
My thought process was that i could set the JFrame's layout to a BorderLayout so that i can brake the final layout down into two parts, the West one and the East one. The West one would contain the Grid and the various JLabels and Buttons and the East one would contain the rest of the components. I've tried using the BorderLayout.WEST & EAST parameters when adding components to the JFrame but none has worked or changed a single thing. I've also tried using an index for the depth when adding components to the JLayeredPane as per the docs but again nothing changes.
P.S. Please note that i'm not looking for someone to create the layout for me. I want someone to help me understand what i'm doing wrong and what the best way of creating such layouts is.

In order to initialize the cells of the grid that i want to have images in, don't i need to add them manually in those positions?
If you use a GridLayout every cell must have a component and the components must be added in sequential order. That is as components are added they will wrap automatically to the next row as required.
So even if you don't want an image in a cell you would need to add a dummy component, lets say a JLabel with no text/icon.
An easier approach might be to use a GridBagLayout. The GridBagLayout can be configured to "reserve" space for cells that don't have components. So you can add a component to a specific cell.
import java.awt.*;
import java.util.*;
import javax.swing.*;
import javax.swing.border.*;
public class GridBagLayoutSparse extends JPanel
{
public GridBagLayoutSparse()
{
setBorder( new LineBorder(Color.RED) );
GridBagLayout gbl = new GridBagLayout();
setLayout( gbl );
/*
// Set up a grid with 5 rows and columns.
// The minimimum width of a column is 50 pixels
// and the minimum height of a row is 20 pixels.
int[] columns = new int[5];
Arrays.fill(columns, 50);
gbl.columnWidths = columns;
int[] rows = new int[5];
Arrays.fill(rows, 20);
gbl.rowHeights = rows;
*/
// Add components to the grid at top/left and bottom/right
GridBagConstraints gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.BOTH;
gbc.gridx = 0;
gbc.gridy = 0;
addLabel("Cell 0:0", gbc);
gbc.gridx = 3;
gbc.gridy = 4;
addLabel("Cell 3:4", gbc);
}
private void addLabel(String text, GridBagConstraints gbc)
{
JLabel label = new JLabel(text);
label.setBorder( new LineBorder(Color.BLUE) );
add(label, gbc);
}
private static void createAndShowGUI()
{
JFrame frame = new JFrame("GridBagLayoutSparse");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout( new GridBagLayout() );
frame.add(new GridBagLayoutSparse());
frame.setSize(300, 300);
frame.setLocationByPlatform( true );
frame.setVisible( true );
}
public static void main(String[] args) throws Exception
{
java.awt.EventQueue.invokeLater( () -> createAndShowGUI() );
}
}
Run the code as is and the components will be grouped together in the center.
Uncomment the block comment and run again. The components will be positioned in the appropriate cell.

Java swing GUI absolute positioning

I know that absolute positioning is not recommended, but I need to show my labels randomly scattered as well as randomly changing their positions.
I have researched how to use setBounds but it doesn't seem to work. The following code shows the labels in a Flow Layout, and when I use setLayout(null) it shows a blank frame.
public class GUI extends JFrame{
device mobiles[];
device station;
JPanel pane= new JPanel();
public GUI()
{
setTitle("communication is Key");
setSize(1000, 1000);
setResizable(false);
setDefaultCloseOperation(EXIT_ON_CLOSE);
pane.setBackground(Color.WHITE);
int x=0; int y=0;
mobiles= new device[10];
for (int i = 0; i < 10; i++) {
x=randInt();
y=randInt();
mobiles[i]= new device(1,x,y);
pane.add(mobiles[i]);
}
x=randInt();
y=randInt();
station = new device(0,x,y);
pane.add(station);
this.add(pane);
}
and this is class "devices" that extends JLabel
public class device extends JLabel{
ImageIcon mob = new ImageIcon("mob.png");
ImageIcon tow = new ImageIcon("tower.png");
public device(int num, int x, int y)
{ if(num==1)
this.setIcon(mob);
else this.setIcon(tow);
this.setBounds(x, y, 3, 7);
}
}
any help in finding out what the problem is, would be be appreciated.

The following code shows the labels in a Flow Layout, and when I use setLayout(null) it shows a blank frame.
The layout manager sets the size and location of the component.
If you don't use the layout manager, then you are responsible for set the size and location of each component.
Typically I would set the size to equal to the components preferred size.
Also, did you display the x/y value that are randomly generated? Maybe the values are larger than the size of the panel.
and when I use setLayout(null) it shows a blank frame.
What layout is set to null? The panel of the frame. Your code doesn't use the above method. Post the code that you use to cause the problem. We don't want to guess what you may or may not be doing.

thanks to #CasparNoree ... the answer suggested was to initialize the Japnel from the start:
JPanel pane = new JPanel(null);

When you set the layout to null you can set the bounds manually with coordinates.
JFrame jf = new JFrame();
JPanel p = new JPanel();
JButton jb = new JButton();
// this is where you make it so setting the bounds actually does something
p.setLayout(null);
jb.setBounds(100,100,100,100);
p.add(jb);
jf.add(p);
jf.setVisible(true);

JPanel taking up more space than it needs. How can I shrink it?

UPDATE: I have received justified criticism for posting non working code. I've taken that to heart and am updating this post with a complete working example. I'm also updating the description accordingly:
I have a very simple java swing GUI whose components take up what looks to be an equal amount of vertical (Y) space as is used by the largest Y extent component, but completely unnecessarily so. I have tried to shrink those components that don't need that much vertical space using preferredSize hints but to no avail.
The basic layout is simple: There's a main window and three vertical panels. The layout is a simple GridLayout (and I would prefer to keep it that way, unless someone shows me what I need cannot be done with GridLayout). All three panels seem to be occupying the same amount of vertical space, even though in the case of the sliders, this is massive waste of space. How can I get each of the sub-panes to only use as much space as they each need? i.e. I would like the two slider windows to be only as tall as the sliders and their description need to be.
The code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class test {
public static void main(String[] arg) {
JFrame mainWindow = new JFrame();
JSlider slider1 = new JSlider(0,100,50);
JSlider slider2 = new JSlider(0,100,50);
JPanel pnlSlider1 = new JPanel();
pnlSlider1.setLayout(new GridLayout(1,1)); // 1 row, 1 column
pnlSlider1.add(new JLabel("Description for slider1"));
pnlSlider1.add(slider1);
JPanel pnlSlider2 = new JPanel();
pnlSlider2.setLayout(new GridLayout(1,1)); // 1 row, 1 column
pnlSlider2.add(new JLabel("Description for slider2"));
pnlSlider2.add(slider2);
// label should now be to the left of slider
String content = "<html>Some rather long winded HTML content</html>";
JEditorPane ep = new JEditorPane("text/html", content);
// this is the main window panel
JPanel panel = new JPanel();
panel.setLayout(new GridLayout(3,1)); // 3 rows, 1 column
panel.add(ep);
panel.add(pnlSlider1);
panel.add(pnlSlider2);
// tie it all together and display the window
mainWindow.setPreferredSize(new Dimension(300, 600));
mainWindow.setLocation(100, 100);
mainWindow.getContentPane().add(panel);
mainWindow.pack();
mainWindow.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
mainWindow.setVisible(true);
}
}
(removed rant about not having seen any GUI coding advances in 30 years as that's not pertinent to the problem and likely won't be solved in this post either)

..components take up what looks to be an equal amount of vertical (Y) space as is used by the largest Y extent component, but completely unnecessarily so.
Yes, that is the way GridLayout is designed to work.
Use a GridBagLayout or BoxLayout or GroupLayout instead, each of which can do a single column or row of components of variable size (width and height).

Java: How to nest JPanel in a GridLayout?

I want to know how to nest JPanels using a GridLayout. This is how it should look like.
I approached this problem by 2 ways so far,
using JPanels and
using JLabels,
and none of them worked (only the first panel created is shown).
Here is the code for the JPanel approach:
int x=20, y=20;
JPanel [] panels = new JPanel[3];
JLabel animal = new JLabel(new ImageIcon(getClass().getResource("Pictures/animal.gif")));
JLabel map = new JLabel(new ImageIcon(getClass().getResource("Pictures/map.gif")));
JLabel mountain = new JLabel(new ImageIcon(getClass().getResource("Pictures/mountain.gif")));
for(int i=0;i<panels.length;i++)
{
if(i>0)
{
x+=x;
y+=y;
}
panels[i] = new JPanel(new GridLayout(2,2));
panels[i].setPreferredSize(new Dimension(x,y));
if(i==0)
panels[i].add(new JPanel());
else
panels[i].add(panels[i-1]);
panels[i].add(mountain);
panels[i].add(map);
panels[i].add(animal);
}
add(panels[2]);

One option is to create a class that will represent a panel divided into the grid with the images. The only issue would be the top left quadrant which would usually contain the nested panel, at some point you want this to contain just a blank panel. So maybe something like this (barring various optimizations):
class GridPanel extends JPanel{
JLabel mountain, map, animal;
public GridPanel(JPanel panel){
super();
setLayout(new GridLayout(2, 2));
animal = new JLabel(new ImageIcon(getClass().getResource("pictures/animal.gif")));
map = new JLabel(new ImageIcon(getClass().getResource("pictures/map.gif")));
mountain = new JLabel(new ImageIcon(getClass().getResource("pictures/mountain.gif")));
add(panel);
add(mountain);
add(map);
add(animal);
}
}
Notice that it accepts the panel that is to be displayed in the top left corner of the grid. This coud then be called with the panel specified. So at the point where you want to create the main panel:
JPanel grid = new GridPanel(new JPanel()); //initial
for(int i = 1; i <= 5; i++){
grid = new GridPanel(grid);
}
add(grid);
The initial grid is created with a blank JPanel. And every subsequent grid will contain the previous one as the top left panel. You have to resize your images and such and maybe even avoid loading the images multiple times etc. But that is another question. This example shows 5 nested panels.
Just to be clear, you should use ImageIO to load the images once and reuse the images. For example You can create a BufferedImage like this in your main class:
BufferedImage mointainImg = ImageIO.read(new File("pictures/mountain.gif"));
And when you want to create the JLabel you can do this:
mountain = new JLabel(new ImageIcon(mountainImg));
And the advantage is that you can manipulate the image a bit if you want.

One issue that you have is that the images are not scaled. To scale images, use Image.getScaledInstance(). Proper scaling would at least fix the problem of the visible images being cut off. It also might cause the other images to be shown as they might just be hiding behind the visible images because they are too big.

Tiled images in swing

I have task to prepare two windows with swing. One contains grid of squares, with random numbers in them. In second I need to load pieces of tiled image and then show them in the correct order, forming tiled image.
Windows should look like this :
alt text http://img535.imageshack.us/img535/3129/lab8a.jpg
Okay so how to bite this? I've used swing only few times to draw some 2d polylines, so basically I just theoretically now what to do.
Ok, so window number 1:
I start with creating Jframe for the window. Then I do for loop and in it create 16 JLabels with random numbers in them? How to set margins between each tile and the whole window?
Window number 2:
So I start the same, but instead of loading numbers I add images? Now, how can I load image from file and then set it as background?

The following code lays out the JLabels using the GridLayout. The arguments to the GridLayout are the following: rows, cols, horizontal gap, vertical gap. In the example below I have 3 pixels wide gap between labels both vertically and horizontally.
To use images instead of numbers, you could pass an ImageIcon to the constructor of the JLabel instead of the text.
However, it looks like your doing a game where the user should be able to click on the tiles. This suggests that you perhaps should use buttons instead of labels, but it's up to you :-)
import java.awt.GridLayout;
import javax.swing.*;
import javax.swing.border.BevelBorder;
public class FrameTest {
public static void main(String[] args) {
final JFrame f = new JFrame("Frame Test");
JPanel panel = new JPanel(new GridLayout(4, 4, 3, 3));
for (int i = 0; i < 16; i++) {
JLabel l = new JLabel("" + i, JLabel.CENTER);
//JLabel l = new JLabel(new ImageIcon("image_file.png"), JLabel.CENTER);
l.setBorder(BorderFactory.createBevelBorder(BevelBorder.RAISED));
l.setFont(l.getFont().deriveFont(20f));
panel.add(l);
}
f.setContentPane(panel);
f.setSize(200, 200);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
}