Browsing .png files?

[Norm]

What do you know about OOP programming. Your question implies that you need to do a bit of studying before trying to write a program.

 content.add(ImageDisplay(_fileNameTF));

If this is the statement with the error, it says to call the ImageDisplay method and pass it a JTextField reference.
The method is to return a component that can be added to the content panel.
There is a class named ImageDisplay but there is NOT a method named ImageDisplay.

[petur170]

OK so i fixed it (sorta) Now i can actually run it without an error, but when i load the image, it has this error:

javax.imageio.IIOException: Can't read input file!
	at javax.imageio.ImageIO.read(Unknown Source)
	at DesaturateApplet.ImageDisplay.ImageDisplay(ImageDisplay.java:23)
	at DesaturateApplet.ImageBrowser$OpenAction.actionPerformed(ImageBrowser.java:90)
	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at javax.swing.AbstractButton.doClick(Unknown Source)
	at javax.swing.plaf.basic.BasicMenuItemUI.doClick(Unknown Source)
	at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$000(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.awt.EventQueue$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.awt.EventQueue$2.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

[Norm]

Print out the name of the file being opened to see if that is ok.

[petur170]

its not working either. Hmm.

[Norm]

Strange that a println wouldn't work.

[petur170]

Ohh i thought you meant something else. println worked.

[petur170]

------removed------

[petur170]

Ok, so i combined it all too one class and fixed all the errors, now i can load a image without any errors, but it doesnt display anything. My full code:

package DesaturateApplet;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

import java.awt.image.BufferedImage;
import java.io.*;

import javax.imageio.ImageIO;
import javax.swing.*;

public class ImageBrowser extends JFrame{

    //====================================================== fields
    JTextField   _fileNameTF  = new JTextField(15);
    JTextField   _wordCountTF = new JTextField(4);
    JFileChooser _fileChooser = new JFileChooser();

    //================================================= constructor
    ImageBrowser() {
    	String newline = System.getProperty("line.separator");

        _fileNameTF.setEditable(false);
        _wordCountTF.setEditable(false);

        JPanel content = new JPanel();
        content.setLayout(new FlowLayout());
        content.add(new JLabel("File Name:" + newline));
        content.add(_fileNameTF);
        content.add(new JLabel(newline + "Preview:"));


        JMenuBar menubar  = new JMenuBar();
        JMenu    fileMenu = new JMenu("File");
        JMenuItem openItem = new JMenuItem("Open...");
        openItem.addActionListener(new OpenAction());

        menubar.add(fileMenu);
        fileMenu.add(openItem);

        this.setJMenuBar(menubar);
        this.setContentPane(content);
        this.setTitle("Select a Image File");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.pack();                      // Layout components.
        this.setLocationRelativeTo(null); // Center window.
    }
    public static String fileimage;

    ///////////////////////////////////////////////////// OpenAction
    class OpenAction implements ActionListener {

		public void actionPerformed(ActionEvent ae) {

            int retval = _fileChooser.showOpenDialog(ImageBrowser.this);
            if (retval == JFileChooser.APPROVE_OPTION) {

                File file = _fileChooser.getSelectedFile();


                _fileNameTF.setText(file.getName());
                File filetemp = _fileChooser.getSelectedFile();
                String fileimage = filetemp.getName();
            }

        }
    }
  
    //========================================================= main
    static String path = fileimage;
    public static void main(String[] args) throws IOException{
        JFrame window = new ImageBrowser();
        window.setVisible(true);
        BufferedImage image = ImageIO.read(new File(path));
        ImageBrowser test = new ImageBrowser(image);

        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.add(new JScrollPane(test));
        window.setSize(400,400);
        window.setLocation(200,200);
        window.setVisible(true);
    }
    private static void showIcon(BufferedImage image) {
        ImageIcon icon = new ImageIcon(image);
        JLabel label = new JLabel(icon, JLabel.CENTER);
        JOptionPane.showMessageDialog(null, label, "icon", -1);
    }
    BufferedImage image;
    Dimension size = new Dimension();

    public ImageBrowser(BufferedImage image) {
        this.image = image;
        size.setSize(image.getWidth(), image.getHeight());
    }
    static String imgfile = fileimage;

    protected void paintComponent(Graphics g) {
        int x = (getWidth() - size.width)/2;
        int y = (getHeight() - size.height)/2;
        g.drawImage(image, x, y, this);
    }

    public Dimension getPreferredSize() { return size; }


	
}

[Norm]

I get the following exception when I execute your code:

Exception in thread "main" java.lang.NullPointerException
at java.io.File.<init>(File.java:222)
at ImageBrowser2.main(ImageBrowser2.java:77)

The value of path is not set when line 77 is executed.

[Norm]

Cross posted at Displaying an Image Problem

[petur170]

It is set...

    static String path = fileimage;

    BufferedImage image;
    Dimension size = new Dimension();

    public ImageBrowser(BufferedImage image) {
        this.image = image;
        size.setSize(image.getWidth(), image.getHeight());
    }
    static String imgfile = fileimage;

    protected void paintComponent(Graphics g) {
        int x = (getWidth() - size.width)/2;
        int y = (getHeight() - size.height)/2;
        g.drawImage(image, x, y, this);
    }

    public Dimension getPreferredSize() { return size; }
    public static void main(String[] args) throws IOException{
        JFrame window = new ImageBrowser();
        window.setVisible(true);
        BufferedImage image = ImageIO.read(new File(path));
        ImageBrowser test = new ImageBrowser(image);

        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        window.add(new JScrollPane(test));
        window.setSize(400,400);
        window.setLocation(200,200);
        window.setVisible(true);
    }
    private static void showIcon(BufferedImage image) {
        ImageIcon icon = new ImageIcon(image);
        JLabel label = new JLabel(icon, JLabel.CENTER);
        JOptionPane.showMessageDialog(null, label, "icon", -1);
    }

[Norm]

What value is it set to?
Add a println to show its value just before you try to use it.

[Norm]

What value is it set to?
Add a println to show its value just before you try to use it.

Do you having any programming experience in any language.
There are things about how you have put this program together that makes me wonder if you know how computer programs execute.

[petur170]

Yes im a noob. (im 10 so i dont know much about computers :( )
It says the name of the file and the file extension, but there is no file directory (that matter's right?)

[Norm]

BufferedImage image = ImageIO.read(new File(path));

Are you sure the variable path has a value when the above line executes? Did you print its value out just before the above line was executed?
What printed out?

[petur170]

oooh it says null until i load a file. I made a default file for it to use before i load an image. But it doesnt display...
This is the new error (with the default file name printed)

default.png
Exception in thread "main" javax.imageio.IIOException: Can't read input file!
	at javax.imageio.ImageIO.read(Unknown Source)
	at DesaturateApplet.ImageBrowser.main(ImageBrowser.java:97)

[Norm]

The problem is that The program can not read the file.
Lots of reasons for that. File doesn't exist, it's in another folder, the OS has a lock on it,....

[petur170]

its in the same folder, it does exist, and its not locked. Tried someother things, still hasnt worked.

[Norm]

Sorry, I can't see how your files are arranged or how you are executing the code.
Try this:
Remove the package statement from the source and recompile the program
Open a command prompt, change directory to the folder with the image and the java .class file
Enter the command: dir
to show all the files.
Execute the java program: java ImageBrowser
To copy the contents of the command prompt window:
Click on Icon in upper left corner
Select Edit
Select 'Select All' - The selection will show
Click in upper left again
Select Edit and click 'Copy'

Paste here.

[petur170]

Exception in thread "main" java.lang.NoClassDefFoundError: ImageBrowser (wrong n
ame: DesaturateApplet/ImageBrowser)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(Unknown Source)
        at java.security.SecureClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.defineClass(Unknown Source)
        at java.net.URLClassLoader.access$100(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)