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Java - Swing library - JComboBox on top of JLabel with image - invisible JLabel [duplicate]

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It's my first post here, trynna be quick.
I have a small JFrame window with JLabel with image as a background to said JFrame. JFrame also has 2 JButtons. To this point it worked well, until I decided to add JComboBox. Result of this action is now when I run my JFrame it shows blank, no background image from JLabel, no ComboBox visible, JButtons are shown tho. When I resize even a little this window, JLabel background image appears and everything is fine but it should be without resizing. What am I missing here? I'm very fresh with swing and am doing "game" for my java class project. Here is screenshots and code:
Running
After resizing
public class View_Startup extends JFrame {
JLabel lBackground;
JButton bStart,bExit;
JComboBox cbResolutions;
ImageIcon iBackground,iStart,iExit;
Image icon;
String resolutions[] = {"1280x720 HD","1366x768 WXGA","1600x900HD+","1920x1080 fullHD"};
public View_Startup() {
iBackground = new ImageIcon("xdddddddddd/resolution_background.jpg");
iStart = new ImageIcon("xddddddddddd/iStart2.png");
iExit = new ImageIcon("xdddddddddd/iExit2.png");
this.setSize(656,399);
this.setTitle("xddddddddd");
this.icon = Toolkit.getDefaultToolkit().getImage("C:xdddddddddd\\images.jpg");
this.setIconImage(icon);
this.setVisible(true);
this.setLayout(null);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice defaultScreen = ge.getDefaultScreenDevice();
Rectangle rect = defaultScreen.getDefaultConfiguration().getBounds();
int x=(int) rect.getMaxX();
int y=(int) rect.getMaxY();
this.setLocation(x/2-328,y/2-199);
bStart = new JButton(iStart);
bStart.setBounds(490,240,150,50);
bStart.setOpaque(false);
bStart.setContentAreaFilled(false);
//bStart.setBorderPainted(false);
add(bStart);
bExit = new JButton(iExit);
bExit.setBounds(490,300,150,50);
bExit.setOpaque(false);
bExit.setContentAreaFilled(false);
//bExit.setBorderPainted(false);
add(bExit);
cbResolutions = new JComboBox(resolutions);
cbResolutions.setBounds(490,180,150,50);
add(cbResolutions);
lBackground = new JLabel(iBackground);
lBackground.setBounds(0,0,640,360);
add(lBackground);
}
}

Several problems here:
You're using null layouts, a dangerous and kludgy thing to do
You're calling setVisible(true) on the JFrame before you've fully constructed it. Only call this after adding all components.
You're using a JLabel as a background image displayer, but not using it also as a container to hold components.
Instead consider
Using a JPanel's paintComponent method to display the background image
Add this JPanel to your JFrame's contentPane or make it the contentPane
Give it a decent layout (and if need be, add nested non-opaque JPanels each with their own layouts if you need complex layouts)
Call .setVisible(true) on your JFrame after adding all components.
Something like this:
can be created with this code:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;
public class LayoutExample extends JPanel {
private static final long serialVersionUID = 1L;
private BufferedImage background;
private JButton startButton = new JButton("Start");
private JButton exitButton = new JButton("Exit");
private JComboBox<String> combo = new JComboBox<>(new String[] {"1280 x 780 HD"});
public LayoutExample(BufferedImage background) {
this.background = background;
JPanel rightLowerPanel = new JPanel(new GridLayout(0, 1, 5, 5));
rightLowerPanel.setOpaque(false);
rightLowerPanel.add(combo);
rightLowerPanel.add(startButton);
rightLowerPanel.add(exitButton);
JPanel rightPanel = new JPanel(new BorderLayout());
rightPanel.setOpaque(false);
rightPanel.add(rightLowerPanel, BorderLayout.PAGE_END);
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
setLayout(new BorderLayout());
add(rightPanel, BorderLayout.LINE_END);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (background != null) {
g.drawImage(background, 0, 0, this);
}
}
#Override
public Dimension getPreferredSize() {
if (background != null) {
int w = background.getWidth();
int h = background.getHeight();
return new Dimension(w, h);
}
return super.getPreferredSize();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
private static void createAndShowGui() {
String imgPath = "https://pbs.twimg.com/media/DRHUe_tV4AA96G4.jpg";
BufferedImage img = null;
try {
URL imageUrl = new URL(imgPath);
img = ImageIO.read(imageUrl);
} catch (IOException e) {
e.printStackTrace();
System.exit(1);
}
LayoutExample mainPanel = new LayoutExample(img);
JFrame frame = new JFrame("LayoutExample");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
}

Platform independent Image in java

I am trying to paint an image onto a panel, that is contained by a frame.
Let us say I have a 320 x 480 image.
When i try to create a frame with size 320x480 and add the panel into it, I encounter a problem.
In different operating systems, the JFrame of 320x480 is of different sizes due to title bar.
Thus my correct fit image in windows XP will not be properly painted in Windows8 or Ubuntu.
A grey patch is visible because the image was not properly placed.
I tried overriding paint method and using ImageIcon.
Please do offer a solution.
TIA
Code Snippet
CLASS PA CONTENTS
setPreferredSize(new Dimension(500,500));
.
.
JLabel image= new JLabel();
ImageIcon background = new ImageIcon(getClass().getClassLoader().getResource("Flower.jpg"));
image.setBounds(0, 0, 500, 500);
image.setIcon(background);
this.add(image); //where "this" is extending from JPanel
CLASS PB CONTENTS
frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
inserting(frame.getContentPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setResizable(false);
private void inserting(Container pane)
{
cardPanel=new JPanel();
CardLayout cards=new CardLayout();
cardPanel.setLayout(cards);
PA home= new PA();
cardPanel.add(home,"homeScreen");
pane.add(cardPanel);
}

Don't call setSize at all, call pack (as VGR stated in his comment). pack will size your JFrame based on size's of component's within it, and gaps between those component's.
Now.. issue you will encounter is that your JFrame will be small at startup. So override getPreferredSize method for your JPanel to return dimensions of your image:
public void getPreferredSize() {
return new Dimension(image.getWidth(), image.getHeight());
}
Now your image will fit perfectly and your application will be fully OS independent.
And also, do not override paint method. Instead, override paintComponent.
Here is a small demo I made in cases like yours:
import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
public class Drawing {
JFrame frame = new JFrame();
public Drawing() {
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.add(new Panel());
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Drawing();
}
});
}
class Panel extends JPanel {
BufferedImage image = null;
Panel() {
try {
image = ImageIO.read(new File("path-to-your-image"));
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, this);
}
#Override
public Dimension getPreferredSize() {
// Panel will be sizes based on dimensions of image
return new Dimension(image.getWidth(), image.getHeight());
}
}
}

It seems to be the layout problem. The most obvious solution is to wrap you image panel into another container with proper layout, so your panel will always have the same size.

How set location of an image in a JFrame

I'm trying to set the the location of an image in a JFrame. I thought label.setLocation(100, 100); would set the location of the image to 100, 100 (top left corner), but it doesn't seem to do anything no matter were I put it. I even tried panal.setLocation(100, 100). Both do nothing, I get no errors and the image does appears but at 0, 0. What am I doning wrong? Here's my code:
import javax.swing.*;
public class DisplayImage {
public DisplayImage() {
JFrame frame = new JFrame("Display Image");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = (JPanel)frame.getContentPane();
JLabel label = new JLabel();
label.setIcon(new ImageIcon("src/img/school.png"));
label.setLocation(100, 100);
panel.add(label);
frame.setLocationRelativeTo(null);
frame.pack();
frame.setVisible(true);
}
public static void main (String args[]) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new DisplayImage();
}
});
}
}

By default a JFrame uses a BorderLayout. When you add your label to the frame the label is added to the CENTER of the BorderLayout. The layout manager will override the location.
One simple solution is to add an EmptyBorder to the label with the top/left insets being 100. Then instead of add the label to the center you would add the label to the NORTH. The code would be something like:
label.setBorder( new EmptyBorder(...) );
panel.add(label, BorderLayout.SOUTH);
As a general rule you should not be trying to specify exact location of a component. Let the layout managers to their jobs.

The JFrame, by default, uses a BorderLayout as it's layout manager. This will override any settings you supply to the setLocation method.
You have a number of options...
Use something like JLayeredPane, which does not, but default, have layout manager of it's own set by default. See How to use layered panes for more details
Create a custom component capable of renderering the image where you want it. Check out Performing Custom Painting for more details
Create your own layout manager that performs the operations you want...

This works for me:
import java.awt.Dimension;
import javax.swing.*;
public class DisplayImage {
public DisplayImage() {
JFrame frame = new JFrame("Display Image");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = (JPanel)frame.getContentPane();
panel.setLayout(null);
JLabel label = new JLabel();
label.setIcon(new ImageIcon("rails.png"));
panel.add(label);
Dimension size = label.getPreferredSize();
label.setBounds(100, 100, size.width, size.height);
frame.setSize(300, 200);
frame.setVisible(true);
}
public static void main (String args[]) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new DisplayImage();
}
});
}
}
But you should read this:
http://docs.oracle.com/javase/tutorial/uiswing/layout/none.html

In Java, every time I add more than one thing to a JPanel, the second thing is not created?

I create a JPanel and added a few simple buttons with listeners attached to them. Then I decided to add an Image to the background of my panel, so I switched my JPanel to an ImagePanel. The buttons were working on JPanel, but now that I added a bunch of code for the background image to be displayed, the buttons no longer show. I did not change of any of the button adding code so I'm very confused as to why the buttons no longer show. This also happened in my separate GameFrame class. I added 2 rectangle components to a panel, then 3 buttons. For that panel, only the buttons show, despite the rectangles working before the buttons were added. Can I only have one type of JComponent per panel or something? I really do not understand why it's doing this. Thank you for your time.
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TitleFrame extends JFrame
{
private ImagePanel panel;
private JButton mage;
private JButton rogue;
private JButton warrior;
private Image image;
public TitleFrame()
{
JFrame frame = new JFrame();
frame.setSize(1024, 768);
frame.setTitle("Title Screen");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
createMageButton();
createRogueButton();
createWarriorButton();
ImagePanel panel = new ImagePanel(new ImageIcon("C:/Users/Derek Reitz/Documents/Eclipse Projects/GameApp/src/background.jpg").getImage());
panel.add(mage);
panel.add(rogue);
panel.add(warrior);
panel.paintComponent(frame.getGraphics());
frame.getContentPane().add(panel);
}
private void createRogueButton() {
rogue = new JButton("Select Rogue");
class AddButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
moveToNextFrame('r');
}
}
ActionListener listener = new AddButtonListener();
rogue.addActionListener(listener);
}
private void createWarriorButton() {
warrior = new JButton("Select Warrior");
class AddButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
moveToNextFrame('w');
}
}
ActionListener listener = new AddButtonListener();
warrior.addActionListener(listener);
}
private void createMageButton() {
mage = new JButton("Select Mage");
class AddButtonListener implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
moveToNextFrame('m');
}
}
ActionListener listener = new AddButtonListener();
mage.addActionListener(listener);
}
public void moveToNextFrame(char c)
{
GameFrame game = new GameFrame(c);
}
class ImagePanel extends JPanel
{
private Image img;
public ImagePanel(Image img) {
this.img = img;
Dimension size = new Dimension(img.getWidth(null), img.getHeight(null));
setPreferredSize(size);
setMinimumSize(size);
setMaximumSize(size);
setSize(size);
setLayout(null);
}
public void paintComponent(Graphics g) {
g.drawImage(img, 0, 0, null);
}
}
}

You need to use a LayoutManager.
You should then be able to add your ImagePanel and buttons to the contentPane and have them all layed out and visible.
Try the follwoing:
JFrame frame = new JFrame();
frame.setTitle("Title Screen");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
createMageButton();
createRogueButton();
createWarriorButton();
ImagePanel panel = new ImagePanel(new ImageIcon(".../background.jpg").getImage());
panel.setLayout(new FlowLayout());
panel.add(mage);
panel.add(rogue);
panel.add(warrior);
frame.getContentPane().add(panel);
frame.pack();
frame.setVisible(true);

You set as layout null. That is a special case where absolute positions of the components are accepted. So use `setBounds(x, y, width, height). Better still use a real layout.
Another remark, you can take the image from the class path, say from out of the resulting .jar file):
URL url = getClass().getResource("/background.jpg");
... new ImageIcon(url);

how to make image resizeable

i try to make imageviewer, the code is below
import javax.swing.*;
import java.awt.event.*;
import java.IO.*;
public class javaImageViewer extends JFrame{
public javaImageViewer(){
setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setSize(200,100);
JButton openButton = new JButton("Open Images");
getContentPane().add(openButton);
openButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e){
JFileChooser chooser = new JFileChooser(".");
int status = chooser.showOpenDialog(javaImageViewer.this);
if(status == JFileChooser.APPROVE_OPTION){
try{
JFrame frame = new JFrame();
JLabel label = new JLabel(new ImageIcon(chooser.getSelectedFile().toURL()));
frame.add(label);
frame.setSize(500,500);
frame.setVisible(true);
}
catch(Exception e2){
System.out.println("Error"+e2);
}
}
}
});
}
public static void main(String [] args){
javaImageViewer tim = new javaImageViewer();
tim.setVisible(true);
}
}
but when i open image from camera, it always showing over the frame size
i dont know how to make the image follow my frame size ?

in order to place your image with the Full Size, you can try to make your own JPanel, override the paintComponent method, and inside this method use g.DrawImage ,
other solution and maybe easier is set the JPanel dimesion with the same dimesion of you Image and Add this JPanel to a JScrollPane , in this way is going to show a scrollbars to navigate

depends of reall size in pixels
1) put Image / BufferedImage as Icon/ImageIcon to the JLabel, then image will be resiziable up to real size in pixels
2) resize Image by usage of Image#getScaledInstance(int width, int height, int hints)