Setting frame size to the size of an image

[Yoruichi]

Hello,

I'm trying to add an image to a JPanel, and I want the frame size to be the exact same as the image size but I don't know which functions to use. Here's the code I'm using. Any ideas how to do this?

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.image.BufferedImage;
import java.io.File;

import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class Test {

	public static void main(String[] args)
	{
		EventQueue.invokeLater(new Runnable()
			{
				public void run()
				{
					MyFrame frame = new MyFrame();
					frame.pack();
					frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
					frame.setVisible(true);
					frame.setResizable(false);
				}
			});
	}
}

class MyFrame extends JFrame
{
	private JPanel imagePanel;
	BufferedImage image;
	Dimension dim;
	
	public MyFrame()
	{
		setTitle("Lab 7 tester");
		
		try{
			image = ImageIO.read(new File("simple.png"));
			
		} catch (Exception e){
			e.printStackTrace();
		}
		
		dim = new Dimension();
		dim.height = image.getHeight();
		dim.width = image.getWidth();
		
		imagePanel = new JPanel(){
			
			public void paint(Graphics g)
			{
				super.paint(g);
				g.drawImage(image, 0, 0, null);
			}
		};
		
		imagePanel.setPreferredSize(dim);
		add(imagePanel);
		
	}
	
}

Thanks.

[hardwired]

import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;


public class Explore {

    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                MyFrame frame = new MyFrame();
                frame.pack();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setVisible(true);
            }
        });
    }
}

class MyFrame extends JFrame
{
    private JPanel imagePanel;
    BufferedImage image;
    Dimension dim = new Dimension();  // instantiate dim

    public MyFrame()
    {
        setTitle("Lab 7 tester");
        //setSize(300,300);
        String path = "http://www.java-forums.org/images/ca_evo/misc/logo.gif";
        try{
            URL url = new URL(path);
            System.out.println("url = " + url);
            image = ImageIO.read(url);

        } catch (IOException e){
            System.out.println(e.getMessage());
        }
        dim.height = image.getHeight();  // dim was null
        dim.width = image.getWidth();

        imagePanel = new JPanel(){

            public void paintComponent(Graphics g)
            {
                super.paintComponent(g);
                g.drawImage(image, 0, 0, null);
            }
        };
        imagePanel.setPreferredSize(dim);
        add(imagePanel);
    }
}

[Yoruichi]

Sorry, I forgot to initialize dim.
The frame is the same size as the image now, however when i set resizable to false, it becomes a bit bigger. Why is that?

[hardwired]

Why is that?
Frames are created with a peer which is platform-dependent.

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

public class Explore
{
    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                MyFrame left  = new MyFrame(true, new Point(25,25));
                explore(left);
                MyFrame right = new MyFrame(false, new Point(400,25));
                explore(right);
                Dimension d = getPanelSize(left);
                System.out.printf("panel size = [%d, %d]%n",
                                   d.width, d.height);
            }
        });
    }

    private static void explore(JFrame frame) {
        Dimension size = frame.getSize();
        System.out.printf("%6s resizable size = [%d, %d]%n",
                           frame.isResizable() ? "is" : "is not",
                           size.width, size.height);
        Insets insets = frame.getInsets();
        System.out.printf("insets = [%d, %d, %d, %d]%n",
                           insets.top, insets.left,
                           insets.bottom, insets.right);
        System.out.println("----------------------");
    }

    private static Dimension getPanelSize(Container parent)
    {
        Component[] c = parent.getComponents();
        for(int i = 0; i < c.length; i++)
        {
            //System.out.println(c[i].getClass().getSimpleName());
            if(c[i] instanceof JPanel)
            {
                return c[i].getSize();
            }
            if(((Container)c[i]).getComponentCount() > 0)
            {
                return getPanelSize((Container)c[i]);
            }
        }
        return null;
    }
}

class MyFrame extends JFrame
{
    BufferedImage image;

    public MyFrame(boolean resizable, Point loc)
    {
        super("resizable = " + resizable);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setResizable(resizable);
        try{
            File file = new File("images/bison.jpg");
            image = javax.imageio.ImageIO.read(file);

        }
        catch (IOException e)
        {
            System.out.println(e.getMessage());
        }
        JPanel imagePanel = new JPanel()
        {
            public void paintComponent(Graphics g)
            {
                super.paintComponent(g);
                g.drawImage(image, 0, 0, null);
            }
        };
        imagePanel.setPreferredSize(new Dimension(image.getWidth(),
                                                  image.getHeight()));
        add(imagePanel);
        pack();
        setLocation(loc);
        setVisible(true);
    }
}

[Yoruichi]

Problem solved, thanks a lot for the help :)

[hablutzel1]

I was trying to use setSize for a JPanel size... but now it is clear that I should use setPreferredSize() instead, It works even when the Jpanel is empty and with no more than Graphics created using public void paintComponent(Graphics g) ...