We Keep Coding

Creating an Image Icon from a local file for eclipse

So I am trying to add an image to a JLabel object which is added to a JPanel called "topPanel" which is part of a JFrame called
"primaryWindow". I have already declared the "topPanel" and "primaryWindow". I found on other forms that you have to create a separate source folder and add the image file in that folder in order to access it and I did so.
However, when I execute the following, the image does not appear to be on the Label. I know that it has nothing to do with adding the JLabel to the panel properly because when I enter a String into the JLabel constructor, the String appears on the panel. An image however does not appear. Am I properly adding the image? I am using a mac if this helps.
private JLabel image = new JLabel();
image.setIcon(new ImageIcon("Check.png"));
topPanel.add(image);
primaryWindow.add(topPanel, BorderLayout.NORTH);

You can also use BufferedImage
BufferedImage myPicture = ImageIO.read(new File("C:\\xx\\xxx\\Check.png.jpg"));
Image scaled = myPicture.getScaledInstance(100,70,Image.SCALE_SMOOTH);
image = new JLabel(new ImageIcon(scaled));
topPanel.add(image);
primaryWindow.add(topPanel, BorderLayout.NORTH);
Note that "C:\\xx\\xxx\\Check.png.jpg" is the path where you save Check.png.
Hope this helped.

The ImageIcon that you passed into the setIcon method of the JLabel could be null. Have you tried to check if it is null before calling setIcon? If you create a "res" resource folder in the root directory of your project, you could try the following:
image.setIcon(new ImageIcon(ImageIO.read(new File("res/Check.png"))));
Additionally, if you are using Eclipse, you should try and refresh the project directory by right clicking and pressing refresh; sometimes Eclipse doesn't register files added.
Lastly, try setting the background of the JPanel to a certain color to see if it is displaying it and make sure its width and height are not 0 (it is possible that the layout you are using changed its size).

Simple Java GUI, cards not appearing

import javax.swing.*;
public class SlideShow {
JFrame slide = new JFrame("Slide Show");
public SlideShow(){
slide.setSize(300,400);
slide.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
slide.setVisible(true);
slide.setLocationRelativeTo(null);
JPanel panel = new JPanel();
JLabel label = new JLabel(new ImageIcon("Images/picture1"));
panel.add(label);
slide.add(panel);
}
public static void main(String[] args){
SlideShow slide = new SlideShow();
}
}
I have to create a simple Java GUI that displays some cards. First, I just wanted to test it by displaying one card. For some reason I can't seem to figure out why nothing is being displayed.

You haven't actually used a proper file name "Images/picture1". Should be something like "Images/picture1.png" with the file format
Also image files, generally should be read from the class path, if you plan on having them embedded to the program. To do so, you will first need to put the file in the class path. With most IDE build configurations it's as simple as placing the image in the src. So
ProjectRoot
src
images
picture1.png
Then you would read it like
new ImageIcon(getClass().getResource("/images/picture1.png"));
A better approach would be to use ImageIO.read(). If the file path is incorrect, it will throw an exception, so you know where you're going wrong
Image image = ImageIO.read(getClass().getResource("/images/picture1.png"));
ImageIcon icon = new ImageIcon(image);
You will need to put it in the try/catch block
Also do what codeNinja said about the setVisible() after adding component. Also preferably pack() the frame, instead of setSize()

You need to set the Frame visible after you add all necessary components to it. Move slide.setVisible(true); Down to the bottom of the constructor like this:
...
slide.add(panel);
slide.setVisible(true);
Alternatively you can add slide.revalidate(); at the bottom of your constructor.

JFrame's icon not displaying

I've got a Java application with Swing's JFrame as a main GUI unit. I've set the icon to it via setIconImage(). When I run this program in NetBeans, everything works fine and the frame's icon displays. But when I compile it and try to run jar-file (with JRE7), the application has standard icon with Duke. How do I change that icon when running app outside NetBeans?
UPD:
OK, here's the code:
public static void main(String[] args) throws IOException{
URL imgUrl = Polygon.class.getResource("/imgs/icon.png");
Image img = ImageIO.read(imgUrl);
JFrame f = new JFrame();
f.setSize(new Dimension(500, 500));
f.setIconImage(img);
f.setVisible(true);
}
UPD2:
I've added this line to the end of the code:
JOptionPane.showMessageDialog(null, new ImageIcon(img));
Everything's fine with the image! It loads! BUT it's not displayed as the icon.

When you run the application from inside Netbeans, the files from your project folder are available, but if you run the compiled JAR yourself they may not.
Read this example (note the comments) to load your image properly.

Try getClass().getResource("imgs/icon.png"). It works for me. Note the difference between absolute and relative path. You may not need the leading /.

Why is there no image when running from a .jar file?

I'm trying to make my panel show image as background. I already can do that in NetBeans, but when I build my jar and run it image doesn't show there. I know I have to access it differently. I have seen many tutorials but every one of them shows how to do it with ImageIcon, but I don't need that, I need just Image. Can anyone point out what piece of code do I need to do this? Thanks.
This is my code for backgrounded JPanel:
public class JPanelWB extends JPanel { // Creates JPanel with given image as background.
private Image backgroundImage;
public JPanelWB(String fileName){
try {
backgroundImage = ImageIO.read(new File(fileName));
} catch (IOException ex) {
new JDialog().add(new Label("Could not open image."+ex.getMessage()));
}
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
// Draw the background image.
g.drawImage(backgroundImage, 0, 0, getWidth(),getHeight(),this);
}
}

Yeah, you're trying to read in the image as a file -- don't do that since files don't exist within a Jar file. Instead read it in as a resource.
Something like so:
public JPanelWB(String resourceName){
try {
// backgroundImage = ImageIO.read(new File(resourceName));
backgroundImage = ImageIO.read(getClass().getResource(resourceName));
} catch (IOException ex) {
new JDialog().add(new Label("Could not open image."+ex.getMessage()));
}
}
But note that resource path is different from file path. The resource path is relative to the location of your class files.

If you want to read new image and import it as background, people smarter than me already answered your question.
But, if your problem is similar to mine, then this migh help:
If you already have images to show, then the point is to call them from absolute path. Executable class form JAR will read drive created inside virtual machine, not the physical drive in your computer.
Put images in short-pathed folder like
C:\J\proj\img\
and call them with absolute path like
"C:\\J\\proj\\img\\your_image.png" // (Don't forget the double backslashes.)
(If you don't mind path lenght, leave them in image folder inside your project package, and call them from there.)
NetBeans will pack them into JAR with absolute path. On execution JRE will create JVM with that path in it, take the images from JAR and put them to that virtual path. Class will be able to find them, because it doesn't read path from physical drive, but from own virtual one newly created inside JVM.
In that case avoiding ImageIcon is just more clutter, not less.
You can add "blackBoard" as JLabel to be background to your JFrame, set its layout to null, something like this:
private JLabel blackBoard;
private JLabel noteToSelf;
//.....
blackBoard = new JLabel();
noteToSelf = new JLabel();
//.....
// putting JLabel "blackBoard" as background into JFrame
blackBoard.setIcon(new ImageIcon("c:\\Java\\images\\MarbleTable.png"));
getContentPane().add(blackBoard);
blackBoard.setBounds(1, 1, 400, 440);
blackBoard.setLayout(null);
and then add components into "blackBoard" instead of your JFrame, like this.
// putting JLabel "noteToSelf" onto background
noteToSelf.setIcon(new ImageIcon("c:\\Java\\images\\Sticker_a1.png"));
// or: noteToSelf.setText("Remind me at 6:30am...");
blackBoard.add(noteToSelf);
noteToSelf.setBounds(noteX, noteY, 64, 48);
Now your JFrame is table board and "blackBoard" is table sheet on it.
Hope this helps.

Having difficulty add a custom icon to a JFrame

I have been trying to change the icon in the frame. I have virtually tried everything:
The icon is 16x16 which is the right size ....doesn't work
I've trying PNG,GIF and JPG formats none of them work.
Tried different way of setting the icon....doesn't work.
I've tried relative (local paths) e.g. "icon.gif" and absolute paths e.g. "c:\work\java\icon.gif" ...doesn't work
Here is my code and see if you can figure it out
Thanks
Oli
import javax.swing.*;
public class androidDriver
{
public static void main(String[] args) throws IOException
{
JFrame f = new JFrame("Android Data Viewer");
f.setResizable(false);
f.setSize(300,300);
f.setLocationRelativeTo(null);
f.setVisible(true);
f.setIconImage(new ImageIcon("androidIcon2.gif").getImage());
}
}

If you put the image in the same directory as the class file then the following should work for you:
f.setIconImage(new ImageIcon(androidDriver.class.getResource("androidIcon2.gif")).getImage());
Also would suggest setting the icon image before you make the frame visible
f.setIconImage(new ImageIcon(androidDriver.class.getResource("androidIcon2.gif")).getImage());
f.setVisible(true);

I suspect you may have to actually wait for the image to load using a MediaTracker. It's likely that the image is still loading at the point the frame setIconImage references it, so it does nothing.

Have you tried using Toolkit.getDefaultToolkit().getImage("androidIcon2.gif")
And two other things:
Does the image exist? The code you posted will fail silently.
Is it formatted properly? (though I assume Java could handle it if it wasn't)

Make a separate folder next to the source folder then put your image in there, and then use ImageIO to get the image like so:
f.setIconImage(ImageIO.read(new File("res/androidIcon2.gif")));
Also, if that doesn't work, try saving the image as a .png instead of a .gif.