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Dynamically Add Image To JLabel [closed]

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I am attempting to dynamically add an image to my JLabel then add the JLabel to my panel. My code is throwing no errors, but the image is never shown.
public JFrameGamePlay(String playername, String playerselected) {
initComponents();
playerimage = "/Users/owner/Downloads/__Pikachu.png";
ImageIcon pimage = new ImageIcon(playerimage);
JLabel lblPlayer = new JLabel(pimage);
pnlPlayer.add(lblPlayer);
pnlPlayer.validate();
pnlPlayer.repaint();
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new JFrameGamePlay().setVisible(true);
}
});
}
EDIT
So from further googling I came up with this syntax
JLabel lblPlayer;
lblPlayer = new JLabel(new ImageIcon(getClass().getClassLoader().getResource("__Image1.png")));
pnlPlayer.add(lblPlayer);
pnlPlayer.validate();
pnlPlayer.repaint();
but when I run the code I get this debug error:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.ImageIcon.<init>(ImageIcon.java:217)
This is the GUI layout of how I want my data to appear - it is 1 panel on the left and 1 panel on the right - each with a label dynamically created and populated with an image. But no image is being populated.
EDIT 2
I added a black border around my 2 Panels, and when the JForm is loaded neither panel is being displayed. So it seems that what everyone is telling me that GUI designing in NetBeans is pretty buggy. How can I dynamically in my code behind add the two panels one left and one right with a size of 143, 246?
EDIT 3
Still no mustard and I'm using this syntax:
public JFrameGamePlay() {
initComponents();
JPanel leftpanel = new JPanel();
JPanel rightpanel = new JPanel();
JSplitPane pane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftpanel, rightpanel);
JLabel lblPlayer = new JLabel(new ImageIcon("/resources/__Image1.png"));
leftpanel.add(lblPlayer);
leftpanel.validate();
leftpanel.repaint();
}

Use ImageIO.read(File) to read the Image. Like,
File playerimage = new File("/Users/owner/Downloads/__Pikachu.png");
ImageIcon pimage = new ImageIcon(ImageIO.read(playerimage));
JLabel lblPlayer = new JLabel(pimage);
pnlPlayer.add(lblPlayer);

The NullPointerException comes from the getResource("__Image1.png") returning null because it didn't find the file. You should prefix it with the location from the classpath (after all, the ClassLoader loads the file). E.g. if the image is in a res directory in your jar (or in your classpath):
JFrameGamePlay.class.getClassLoader().getResource("/res/__Image1.png")));
Or you can directly give a complete path:
new JLabel(new ImageIcon("/images/thewall.png"));
Example:
public class JFrameGamePlay extends JFrame {
private static final long serialVersionUID = 1L;
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(100, 100, 450, 300);
JPanel contentPane = new JPanel(new BorderLayout());
frame.setContentPane(contentPane);
JLabel label = new JLabel(new ImageIcon("/images/thewall.png"));
contentPane.add(label, BorderLayout.CENTER);
JLabel label1 = new JLabel(new ImageIcon(JFrameGamePlay.class.getResource("/javax/swing/plaf/basic/icons/JavaCup16.png")));
contentPane.add(label1, BorderLayout.NORTH);
frame.setVisible(true);
}
}

My code is throwing no errors, but the image is never added.
Yes, this is unfortunately how ImageIcon works. It doesn't throw exceptions or anything if it's unable to read from the filename or URL you pass to it. The code runs without error but simply shows nothing.
playerimage = "/Users/owner/Downloads/__Pikachu.png";
If you want to read from a file at a fixed location like this, then it won't be helpful to mess with getClassLoader().getResource(). That could be helpful to read an image file that you package with your application, but not to read an image in the user's home directory. Your original new ImageIcon(imageLocation) approach is appropriate for that.
[note: I think it's a good idea to send the filename (or URL) directly to the ImageIcon, as your original code does. Other answers suggest ImageIO.read(), which can be helpful to see where it's going wrong, but you could change it back to ImageIcon(filenameOrUrl) once you get it working. But it's not a big deal.]
I am attempting to dynamically add an image to my JLabel then add the JLabel to my panel.
If by "dynamically" you mean to do this when some event occurs, after the panel is already visible on the screen, then I suggest not doing that.
That is, instead of doing this...
JLabel lblPlayer = new JLabel(pimage);
pnlPlayer.add(lblPlayer);
pnlPlayer.validate();
pnlPlayer.repaint();
...you could add the JLabel to your panel (invisible because no text or image) at the very start, before your panel is shown on screen. Then dynamically add the ImageIcon to the already-extant JLabel. All you need to call is existingLabel.setIcon(...). There would be no need to call validate() or repaint().

Swing Intellij GUIDesigner image disappears if placed in JScrollPane

I'm using IntelliJ GUIDesigner.
I have JScrollPanel which contains JPanel.
The idea is that I want to add image to JPanel and to have it load at full size so I can use scrollers to move around and see whole image.
And My problem is that it paints itself alright if I won't change the size of JPanel. But the moment I'm chaning JPanel size it just repaints itself to orginal state (I suppose, IntelliJ hides a lot of code from me).
The code is:
private JPanel panel1;
private JButton button1;
private JPanel drawingPanel;
public MainPanel(){
button1.addActionListener(e -> {
JFileChooser openFile = new JFileChooser();
File chosenFile;
if(openFile.showSaveDialog(panel1) == JFileChooser.APPROVE_OPTION){
chosenFile = openFile.getSelectedFile();
drawImage(chosenFile);
}
});
}
private void drawImage(File file){
try {
BufferedImage image = ImageIO.read(file);
//Works OK if line belowed is removed, but doesn't adjust size so I can't scroll.
drawingPanel.setSize(image.getWidth(), image.getHeight());
Graphics g = drawingPanel.getGraphics();
g.drawImage(image, 0, 0, null);
drawingPanel.paintComponents(g);
}
catch (IOException e) {
e.printStackTrace();
}
}
As I wrote in comment, if the line below the comment is removed then I can load the image and it shows OK but it's too big and I can't see whole image.
If I add the line then it just clears everything and I can't see nothing.
This is important - I need to get the image to show in full size.
How do I do it?

I have JScrollPanel which contains JPanel.
Don't do custom painting.
Just create a JLabel and add the label to the viewport of the scroll pane. Then when you want to change the image you use the setIcon(...) method of the JLabel and the label will automatically repaint itself and scrollbars will appear if necessary.

Maybe you can share your IntelliJ GUI forms? Otherwise it's difficult to reproduce the scrolling problem that you're facing. Without the custom painting and using a label as camickr suggested, you can get scrolling working like this:
public class MainPanel {
private static JFrame frame;
private JPanel panel1;
private JButton button1;
private JPanel drawingPanel;
private JLabel drawingLabel;
public static void main(String[] args) {
MainPanel.test();
}
private static void test() {
frame = new JFrame("");
frame.setBounds(100, 100, 640, 480);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
new MainPanel();
frame.setVisible(true);
}
public MainPanel() {
initializeGui();
button1.addActionListener(e -> {
JFileChooser openFile = new JFileChooser("[...]");
File chosenFile;
if (openFile.showSaveDialog(panel1) == JFileChooser.APPROVE_OPTION) {
chosenFile = openFile.getSelectedFile();
System.out.println("chosenFile: " + chosenFile);
drawImage(chosenFile);
}
});
}
private void initializeGui() {
panel1 = new JPanel(new BorderLayout());
frame.getContentPane().add(panel1);
button1 = new JButton("Open image");
panel1.add(button1, BorderLayout.NORTH);
drawingPanel = new JPanel(new BorderLayout());
panel1.add(drawingPanel, BorderLayout.CENTER);
drawingLabel = new JLabel();
drawingPanel.add(new JScrollPane(drawingLabel), BorderLayout.CENTER);
}
private void drawImage(File file){
try {
BufferedImage image = ImageIO.read(file);
//Works OK if line below is removed, but doesn't adjust size so I can't scroll.
// drawingPanel.setSize(image.getWidth(), image.getHeight());
// Graphics g = drawingPanel.getGraphics();
// g.drawImage(image, 0, 0, null);
// drawingPanel.paintComponents(g);
drawingLabel.setIcon(new ImageIcon(image));
drawingPanel.validate();
}
catch (IOException e) {
e.printStackTrace();
}
}
}
Not sure how easy it is to do something similar with the IntelliJ GUI designer; I do prefer IntelliJ (over Eclipse and NetBeans) but I also prefer to create my Java GUIs in code... ;-)

Image won't appear in JLabel

I've created GUI for my application using Netbeans' GUI Builder. I am trying to display a JFrame containing a JLabel with an image, and I can't get the Image to display.
My generated code :
private void initComponents() {
//...
jLabel1 = new JLabel(new ImageIcon(myPicture));
}
And my class code:
public class GUIWindow extends javax.swing.JFrame {
BufferedImage myPicture;
/** Creates new form GUIWindow */
public GUIWindow() throws IOException {
myPicture = ImageIO.read(new File("images/logo.png"));
initComponents();
this.add(jLabel1);
}
}
but I still don't see an image ... (path to the image file is fine) its sth like:
my-project :
/build
/dist
/images/logo.png
/nbproject
/src (here I have all my source files)
/build.xml
/manifest.mf

you can use like this
URL imgSmartURL = this.getClass().getResource("your image path");
jLabel1 = new JLabel(new ImageIcon(imgSmartURL), JLabel.CENTER);

I would do something like this instead.
JLabel dice1 = new JLabel();
ImageIcon one = new ImageIcon("dice/1.png");
//set dice1 position
dice1.setLocation(20, 100);
dice1.setSize(115, 115);
dice1.setIcon(one);
gamepanel.add(dice1);

If you are using netbeans you can directly add an image to a jLabel by setting properties. Right click on the jLabel -> properties -> icon -> (if it's external image) import to project(upload your image) -> ok .
It'l be added into your jLabel.

I'd suggest you copy the image in a seperate folder(images).
Then use Toolkit.getDefaultToolkit().getImage("images/A.png");
I believe there's a similar question

private ImageIcon imageIconPrint =
new ImageIcon(getClass().getResource("/image/print.gif"));
create button and add follwing code:
jbtCanada.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
jlblFlag.setIcon(imageIconCanada);
}
});
this would help i think

Why slideshow not working in Java using Swing and Awt?

I am doing slideshow of images program in java using timer.
In timer event listner i have added code to chnage image but image is not changing.
Below is the code i have written
class ImagePanel extends JPanel {
private Image backgroundImage;
public ImagePanel(Image backgroundImage) {
super();
this.backgroundImage = backgroundImage;
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(this.backgroundImage, 0, 0, null);
}
}
public class A extends JFrame{
static int counter;
List<String> imagePaths;
int nimgpaths=0;
static A frame = new A();
public static void main(String[] args) {
frame.setSize(1024, 768);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getPath();
/* Getting required image */
Image backgroundImage = null;
String pathToTheImage = "C:\\Documents and Settings\\Administrator\\My Documents\\My Pictures\\civ1.JPG";
try {
backgroundImage = ImageIO.read(new File(pathToTheImage));
} catch (IOException e) {
e.printStackTrace();
}
/* Initializing panel with the our image */
ImagePanel panel = new ImagePanel(backgroundImage);
frame.getContentPane().add(panel);
frame.setVisible(true);
frame.timerEvent();
//frame.show();
}
public void timerEvent(){
Timer timer = new Timer(5000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("Time event occured");
if(counter > nimgpaths)
counter=0;
String imgPath=imagePaths.get(counter);
Image backgroundImage = null;
try {
backgroundImage = ImageIO.read(new File(imgPath));
}catch (Exception e1) {
e1.printStackTrace();
}
/* Initializing panel with the our image */
frame.removeAll();
ImagePanel panel = new ImagePanel(backgroundImage);
panel.repaint();
//panel.setBackground(backgroundImage);
frame.getContentPane().add(panel);
}
});
timer.start();
}
// To get path of images
public void getPath(){
DbOps db=new DbOps();
imagePaths=db.getPath();
nimgpaths=imagePaths.size();
for(Iterator i=imagePaths.iterator();i.hasNext();){
System.out.println((String)i.next());
}
}
}

Why are you using a custom panel and painting?
Your code is simply painting the image at its preferred size. This functionality is available when you use a JLabel. Then when you use the label all you need to do is use:
label.setIcon(....);
when you want to change the image. Read the section from the Swing tutorial on How to Use Icons for more information.
The only reason to create a custom component is if you plan to scale the image or do something fancy like that. If this is the case then you can use something like the Background Panel which supports scaled images as well as a setImage() method so you can change the image dynamically.

A much better design for ImagePanel would let you just replace the image, rather than removing the component. If you do have to replace a visible component, though, you have to call validate() on its container, or the new one isn't going to show up (most of the time, anyway.) I think that's your problem here.

frame.removeAll() is not doing what you would expect - it is removing the components from the frame itself rather than removing the components from the content pane of the frame. Change the code at the end of the timer's action listener to something like this to fix it:
ImagePanel panel = new ImagePanel(backgroundImage);
frame.getContentPane().removeAll();
frame.getContentPane().add(panel);
frame.getContentPane().invalidate();
frame.getContentPane().validate();

Your concept itself is wrong.
You can refresh the panel like so:
public void refreshPanel(JPanel panel){
panel.removeAll();
panel.invalidate();
panel.validate();
}
Problem:
I see in your code that you are trying to create more than one object of the same panel, which you need to refresh.
It would be better to create one panel object and refresh that object.
ImagePanel panel = new ImagePanel(backgroundImage);
Hope you can understand what I wanted to explain to you.
If you are still confused then let me know.

How to set an image as a background for Frame in Swing GUI of java?

I have created one GUI using Swing of Java. I have to now set one sample.jpeg image as a background to the frame on which I have put my components.How to do that ?

There is no concept of a "background image" in a JPanel, so one would have to write their own way to implement such a feature.
One way to achieve this would be to override the paintComponent method to draw a background image on each time the JPanel is refreshed.
For example, one would subclass a JPanel, and add a field to hold the background image, and override the paintComponent method:
public class JPanelWithBackground extends JPanel {
private Image backgroundImage;
// Some code to initialize the background image.
// Here, we use the constructor to load the image. This
// can vary depending on the use case of the panel.
public JPanelWithBackground(String fileName) throws IOException {
backgroundImage = ImageIO.read(new File(fileName));
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
// Draw the background image.
g.drawImage(backgroundImage, 0, 0, this);
}
}
(Above code has not been tested.)
The following code could be used to add the JPanelWithBackground into a JFrame:
JFrame f = new JFrame();
f.getContentPane().add(new JPanelWithBackground("sample.jpeg"));
In this example, the ImageIO.read(File) method was used to read in the external JPEG file.

This is easily done by replacing the frame's content pane with a JPanel which draws your image:
try {
final Image backgroundImage = javax.imageio.ImageIO.read(new File(...));
setContentPane(new JPanel(new BorderLayout()) {
#Override public void paintComponent(Graphics g) {
g.drawImage(backgroundImage, 0, 0, null);
}
});
} catch (IOException e) {
throw new RuntimeException(e);
}
This example also sets the panel's layout to BorderLayout to match the default content pane layout.
(If you have any trouble seeing the image, you might need to call setOpaque(false) on some other components so that you can see through to the background.)

The Background Panel entry shows a couple of different ways depending on your requirements.

You can either make a subclass of the component
http://www.jguru.com/faq/view.jsp?EID=9691
Or fiddle with wrappers
http://www.java-tips.org/java-se-tips/javax.swing/wrap-a-swing-jcomponent-in-a-background-image.html

Perhaps the easiest way would be to add an image, scale it, and set it to the JFrame/JPanel (in my case JPanel) but remember to "add" it to the container only after you've added the other children components.
ImageIcon background=new ImageIcon("D:\\FeedbackSystem\\src\\images\\background.jpg");
Image img=background.getImage();
Image temp=img.getScaledInstance(500,600,Image.SCALE_SMOOTH);
background=new ImageIcon(temp);
JLabel back=new JLabel(background);
back.setLayout(null);
back.setBounds(0,0,500,600);

Here is another quick approach without using additional panel.
JFrame f = new JFrame("stackoverflow") {
private Image backgroundImage = ImageIO.read(new File("background.jpg"));
public void paint( Graphics g ) {
super.paint(g);
g.drawImage(backgroundImage, 0, 0, null);
}
};

if you are using netbeans you can add a jlabel to the frame and through properties change its icon to your image and remove the text. then move the jlabel to the bottom of the Jframe or any content pane through navigator

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class BackgroundImageJFrame extends JFrame
{
JButton b1;
JLabel l1;
public BackgroundImageJFrame()
{
setTitle("Background Color for JFrame");
setSize(400,400);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
/*
One way
-----------------*/
setLayout(new BorderLayout());
JLabel background=new JLabel(new ImageIcon("C:\\Users\\Computer\\Downloads\\colorful design.png"));
add(background);
background.setLayout(new FlowLayout());
l1=new JLabel("Here is a button");
b1=new JButton("I am a button");
background.add(l1);
background.add(b1);
// Another way
setLayout(new BorderLayout());
setContentPane(new JLabel(new ImageIcon("C:\\Users\\Computer\\Downloads \\colorful design.png")));
setLayout(new FlowLayout());
l1=new JLabel("Here is a button");
b1=new JButton("I am a button");
add(l1);
add(b1);
// Just for refresh :) Not optional!
setSize(399,399);
setSize(400,400);
}
public static void main(String args[])
{
new BackgroundImageJFrame();
}
}