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Show multiple JPane images on a single JFrame

First off, I am new to JFrame and all the associated classes so I am still learning how to do this.
My current goal is to draw multiple images on a single JFrame. So far, I can get test2.png to draw, but not test1.png. Any suggestions or help understanding JFrame is appreciated. This is my main class:
package com.osj.oneshotjava;
import java.awt.Dimension;
import javax.swing.JFrame;
/**
*
* #author BCG04
*/
public class actorTest {
public static void main(String []args){
JFrame jFrame = new JFrame("OSJ actor test");
jFrame.setPreferredSize(new Dimension(640, 480)); // sets window size
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Actor2 Background = new Actor2(jFrame, "test1.png");
Actor2 testActor = new Actor2(jFrame, "test2.png");
jFrame.pack(); // automatically adjusts window size (also sets window size based on the maximum and minimum sizes)
jFrame.setVisible(true);
}
}
And this is Actor2:
package com.osj.oneshotjava;
import java.awt.BorderLayout;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
/**
*
* #author BCG04
*/
public class Actor2 { //Purpose: make it easer to add multiple images to a single JFrame using only a single call to Actor2's constuctor rather than repeating the same section of code for each image.
private BufferedImage image = null;
private JLabel jLabel = null;
public Actor2(JFrame jFrame, String filename){
try
{ // try to load a image 'filename' into 'image'
image = ImageIO.read(new File(filename));
}
catch (Exception e)
{
e.printStackTrace(); // if loading fails, print the error
System.exit(1); // then exit with an error code 1 'unsuccessful exit'
}
ImageIcon imageIcon = new ImageIcon(image); // create a new ImageIcon that contains 'image'
JPanel jPanel = new JPanel();
jLabel = new JLabel();
jLabel.setIcon(imageIcon); // set JLabel 'jLabel' to contain 'imageIcon'
jPanel.add(jLabel);
jFrame.getContentPane().add(jPanel, BorderLayout.CENTER); // makes window visible?
}
public JLabel getJLabel(){
return jLabel;
}
}
Edit:
-removed Thread.sleep(1000); and setLocation(90, 90); since they were not relevant to the question or the problem and I originally had them in to test whether I could move images.
-removed jLabel.setBounds as it did not seem to do anything.
+added a comment clarifying Actor2's goal.
I'd like to clarify my end goal, I would like to create a simple 2d game that uses Java.

Here is a complete, self contained example that is close to what you're after. It is to demonstrate the use of a layout manager.
import javax.swing.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
public class DuelingJLabels{
public static void startGui(){
JFrame frame = new JFrame();
JPanel scene = new JPanel();
Actor red = new Actor(Color.RED);
Actor blue = new Actor(Color.BLUE);
//scene.setLayout( null );
scene.add(red.image);
scene.add(blue.image);
//scene.setPreferredSize( new Dimension(512, 512) );
frame.add(scene, BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
static class Actor{
int x, y;
JLabel image;
public Actor(Color c){
BufferedImage a = new BufferedImage(64, 64, BufferedImage.TYPE_INT_ARGB);
Graphics g = a.getGraphics();
g.setColor(c);
g.fillOval(0, 0, 64, 64);
image = new JLabel();
image.setIcon(new ImageIcon(a));
image.setLocation( x, y );
image.setSize( 64, 64);
image.addMouseListener( new MouseAdapter(){
#Override
public void mouseClicked(MouseEvent evt){
x = x+64;
if(x>=448){
x = 0;
y += 64;
}
image.setLocation(x, y);
}
});
}
}
public static void main(String[] args){
EventQueue.invokeLater( DuelingJLabels::startGui );
}
}
Take note of the line scene.setLayout(null); if you run the example with that line commented out, then you will see two circles side by side. That is because we are letting swing handle the layout. scene is a JPanel with a FlowLayout by default.
Now when you click the circles, nothing happens* because we tell the new position but the layout manager resets the position.
*Actually they move sometimes, but if you trigger a re-validation then they get moved by the layout manager.
So now remove the comment on scene.setLayout(null); and notice the difference.
The frame is tiny, and we have to manually resize it to see our scene.
There is only one circle.
If you click on the circle, it moves.
That's because we have told swing to not use a layout manager for the JPanel scene. That means it will not reposition the components in the scene for us, and it will not adjust the sizes for us either.
The other line that is commented setPreferredSize makes scene tell the parent component a size it would like to be at. If you uncomment that line then the JFrame will not start out incredibly small. You should only use that with custom components, otherwise you can end up conflicting with the layout manager.
Another tool, which I have found usefull is the JLayeredPane because it gives you some depth. I also think the example is good.
Finally, another technique for putting custom graphics arbitrarily is to #Override paintComponent. That way you can draw whatever, where-ever on your component.

How do I switch a JFrame from being decorated to being not decorated?

I want a game I am making to go fullscreen. I have the game being drawn in a JPanel and added to a JFrame.
I am currently using graphicsDevice.setFullScreenWindow(jframe) to set the JFrame as fullscreen.
The JFrame is decorated. When I set it fullscreen, there is space left for the decoration, but I want it to take up the whole screen. When I have the JFrame as undecorated, it takes up the whole screen when fullscreen.
I want the JFrame to be decorated when in windowed mode, but when in fullscreen mode, I want the screen to be completely used.
I have tried setting the JFrame to be not visible, then changing the decoration and setting it back to visible. I have also tried setting the original to have decoration, making a new JFrame with no decoration and fullscreen with the JPanel added.

I'm not sure but I think you cannot change the setUndecorated() property after a JFrame has become visible. As a result, one solution would be to have two frames. One windowed, one fullscreen. Swap between the frames when you want to toggle fullscreen.
Since you're drawing things onto a JPanel, the solution is to create a draw() method where the drawing will happen. Things do get a little more complicated if you wish to add Swing components though. Anyway, try this out.
Code:
import java.awt.Color;
import java.awt.Graphics;
import java.awt.GraphicsEnvironment;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class FullScreenExample {
public static void main(String[] args) throws InterruptedException {
new FullScreenExample();
}
public FullScreenExample() throws InterruptedException {
// Full screen frame set-up.
JFrame frameFullScr = new JFrame();
frameFullScr.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frameFullScr.setUndecorated(true);
frameFullScr.add(new JPanel() {
#Override
public void paintComponent(Graphics g) {
if(frameFullScr.isVisible()) draw(this, g);
}
});
GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().setFullScreenWindow(frameFullScr);
// Windowed frame set-up.
JFrame frameWin = new JFrame();
frameWin.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frameWin.setSize(512, 512);
frameWin.add(new JPanel() {
#Override
public void paintComponent(Graphics g) {
if(frameWin.isVisible()) draw(this, g);
}
});
Thread.sleep(5000);
// Now let's go into a window...
frameFullScr.setVisible(false);
frameWin.setVisible(true);
}
private void draw(JComponent component, Graphics g) {
g.setColor(Color.ORANGE);
g.fillRect(0, 0, component.getWidth(), component.getHeight());
g.setColor(Color.RED);
g.drawOval(32, 32, 256, 256);
}
}
Just some unrelated advice: In case you run into performance problems, try looking into AWT's BufferStrategy. It is more optimized better accelerated by the graphics card. You can expect a +25% to 75% improvement in framerates.

How to get the painted size of a Swing component?

When I add Swing component (like a JButton) to a JPanel, it renders with it's 'preferred size'.
However, the preferred size is actually larger than the painted button. There appears to be an invisible border around it.
Here's a simple frame with my test panel:
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
TestPanel pnl = new TestPanel();
frame.getContentPane().add(pnl);
frame.pack();
frame.setVisible(true);
Here's my test panel ...
public class TestPanel extends JPanel {
JButton btn1 = new JButton("Test1");
JButton btn2 = new JButton("Test2");
public TestPanel() {
this.add(btn1);
this.add(btn2);
}
public void paint(Graphics g) {
super.paint(g);
g.setColor(Color.RED);
Dimension dim = btn1.getPreferredSize();
g.drawRect(btn1.getX(), btn1.getY(), (int)(dim.getWidth()), (int)(dim.getHeight()));
}
}
Notice I painted btn1's "PreferredSize" in RED to demonstrate that the preferredSize is actually larger than the button itself.
My question is, how can I determine the width and height of the painted button, not the JButton's preferredSize?
Any help is greatly appreciated, thanks!
UPDATE
Because I actually need this to work for all Swing components, here's a screen shot with the more components.
Unfortunately, I need to figure this out, determining the "real" size of the visible widget is crucial to my application.

I don't think this is particular or practically achievable.
The problem is, the button is using the "unpainted" area to paint other elements, like the focus highlight.
You could try look at the AbstractButton#set/getMargin

If nothing better comes along, note that the authors "recommend that you put the component in a JPanel and set the border on the JPanel."
Addendum: Based on your comments below, it's clear that your question is not about rendering borders but about establishing a component's boundary. What you perceive as unused space is actually reserved by the UI delegate for any number of uses, e.g. selection highlighting or esthetic coherence. You can get an idea of how this varies by selecting different Look & Feel themes in the examples here and here.
Using getbounds():
Using setBorder():
import component.Laf;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Rectangle;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.JTextField;
/**
* #see https://stackoverflow.com/a/15490187/230513
*/
public class Test {
private void display() {
JFrame f = new JFrame("Test");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setLayout(new FlowLayout());
// https://stackoverflow.com/a/11949899/230513
f.add(Laf.createToolBar(f));
f.add(decorate(new JButton("Test")));
f.add(decorate(new JTextField("Test")));
f.add(decorate(new JTextArea(3, 8)));
f.add(decorate(new JCheckBox("Test")));
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
private JPanel decorate(final JComponent c) {
JPanel p = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Rectangle r = c.getBounds();
g.setColor(Color.red);
// NB pen hangs down and to the right
g.drawRect(r.x - 1, r.y - 1, r.width + 1, r.height + 1);
}
};
p.add(c);
return p;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new Test().display();
}
});
}
}

Java Swing: problems with width

I have problems with understanding the behavior of my application. I want to create a simple window (1000x700px), divided into two parts (250px and 750px width respectively). I tried the following code:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Example extends JFrame
{
private static final long serialVersionUID = 1L;
public Example()
{
this.setSize(1000, 700);
this.setTitle("Example");
this.setResizable(false);
this.setLayout(new FlowLayout(FlowLayout.LEFT, 0, 0));
JPanel navigation_panel_wrap = new JPanel();
JPanel content_panel_wrap = new JPanel();
navigation_panel_wrap.setPreferredSize(new Dimension(250, 700));
content_panel_wrap.setPreferredSize(new Dimension(750, 700));
content_panel_wrap.setBackground(Color.green);
navigation_panel_wrap.setBackground(Color.red);
this.getContentPane().add(navigation_panel_wrap);
this.getContentPane().add(content_panel_wrap);
}
public static void main(String[] args)
{
Example example = new Example();
example.setVisible(true);
}
}
As you can see I manually set layout manager for JFrame (FlowLayout instead of BorderLayout with zero horizontal and vertical gaps). Of course, I can just use BorderLayout and than use add() method with BorderLayout.EAST and BorderLayout.WEST parameters, but I want to understand what's wrong with FlowLayout.
When I run my application, I get the following (no green JPanel):
If I decrease width of, for example, content_panel_wrap and make it 744px instead of 750px, everything works correctly.
So the question is - what are these strange 6 pixels? I'm not sure this value is constant for all operating systems, so I want to understand its origin.

There's nothing wrong with FlowLayout but you will need to call pack() for all components to be sized.

As for your codes problem (+1 to #Reimeus) calling pack() is the solution.
as per docs:
Causes this Window to be sized to fit the preferred size and layouts
of its subcomponents. If the window and/or its owner are not yet
displayable, both are made displayable before calculating the
preferred size. The Window will be validated after the preferredSize
is calculated.
Tips:
Dont extend JFrame unnecessarily.
Use Event Dispatch Thread when creating and changing UI components:
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
// create UI components etc here
}
});
Dont call setPreferredSize() rather override getPrefferedSize() of component.
Dont call setSize(...) on JFrame rather call JFrame#pack() before setting it visible.
Dont forget to call JFrame#defaultCloseOperation(..) or your initial/EDT thread will not be terminated when JFrame is closed.
Here is an example combining my advice and your code:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Example {
private final JFrame frame;
public Example() {
frame = new JFrame();
frame.setTitle("Example");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//app exited when frame closes
frame.setResizable(false);
frame.setLayout(new FlowLayout(FlowLayout.LEFT, 0, 0));
JPanel navigation_panel_wrap = new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(250, 700);
}
};
JPanel content_panel_wrap = new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(750, 700);
}
};
content_panel_wrap.setBackground(Color.green);
navigation_panel_wrap.setBackground(Color.red);
frame.add(navigation_panel_wrap);
frame.add(content_panel_wrap);
//pack frame (size components to preferred size)
frame.pack();
frame.setVisible(true);//make frame visible
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Example();
}
});
}
}

Problem - Container changing size automatically in Java

I've found that my container is actually changing it's size a short while after being constructed
When it's constructed, I set my components to be at the place I want (like 30px away from the right edge) but later after a short while, I find that it turns from 1008x730 to 1018x740...
(My JFrame is 1024x768)
Does anyone know why this happens and how I can stop this auto-resizing thing?
Thank you.
I just did a -
while (true) {
System.out.println(c.getSize());
}
And the size changed after a few iterations.
~Edited

It sounds like you're doing something that changes a component's size and revalidates after calling pack() on the JFrame. Also, rather than calling setSize(), it's often better to set a component's preferred size and let the LayoutManager arrange things.
Addendum: It's generally better to invoke pack() on a top-level container in order to get the initial sizes correct. Also, the content pane of a JFrame defaults to BorderLayout, which may not be what you want.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class MyPanel extends JPanel {
public MyPanel() {
this.setLayout(new GridLayout(2, 2));
this.setPreferredSize(new Dimension(320, 240));
for (int i = 0; i < 4; i++) {
JLabel label = new JLabel(String.valueOf(i));
label.setHorizontalAlignment(JLabel.CENTER);
label.setBorder(BorderFactory.createLineBorder(Color.blue));
this.add(label);
}
}
private static void create() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new MyPanel());
f.pack();
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
create();
}
});
}
}

If you can run this from your IDE or attach remotely with the debugger it would be pretty easy to just set a breakpoint on the methods that set the size.
Or alternately, you could subclass JFrame with your own class and similarly override those methods and do
try { throw new Exception("here!"); } catch(Exception e) { e.printStackTrace(); }
That would tell you what is causing the change in size.

Sounds like the layout manager kicking in. Try running with the Swing Explorer to see what it thinks of the world.