How to add scrollbar to jpanel with images

[sergey]

I drew on jpanel images.
But cannot add scrollbar on this jpanel which will work.

[Fubarable]

Have you gone through the Sun Swing tutorial on use of scrollbars? Without seeing your code (please use code-tags -- see my signature below), we have no idea what you're doing wrong.

best of luck

[RamyaSivakanth]

Post a code and ask for the solution.

[sergey]

JPanel jpanel = new DrawPane();

JScrollPane scrollPane = new JScrollPane(jpanel);

add(scrollPane);

//**************************
class DrawPane extends JPanel {    
    public void paintComponent(Graphics g){       
            
            super.paintComponent(g);
            Graphics2D g2 = (Graphics2D) g;
            double leftX = 100.;
            double topY = 100.;
            double width = 200.;
            double height = 150.;
            Rectangle2D rect = new Rectangle2D.Double(leftX, topY, width, height);
            g2.draw(rect);
        } 
        
}

[sergey]

I have looked at Sun Swing tutorial, but it seems that all I do is right.

[Fubarable]

I'm not seeing the problem in the code you've posted, so likely the problem is elsewhere (unless I'm missing it, which is not uncommon). I suggest you have a look at this link on SSCCE, and then create and post an SSCCE. This will allow us to work with your problem directly and come up with a solution more quickly.

Much luck!

[sergey]

Full code of application below:

import java.awt.*;
import java.awt.geom.Rectangle2D;
import javax.swing.*;


public class Main {
    public static void main(String[] args) {
       
        JFrame frame = new JFrame();
        JPanel jpanel = new DrawPane();
        JScrollPane scrollPane = new JScrollPane(jpanel);

        frame.add(scrollPane);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(true);
        frame.setLocationByPlatform(true);
        frame.setSize(200,200);
        frame.setVisible(true);

    }
}

class DrawPane extends JPanel {
    @Override
    public void paintComponent(Graphics g){

            super.paintComponent(g);
            Graphics2D g2 = (Graphics2D) g;
            double leftX = 100.;
            double topY = 100.;
            double width = 200.;
            double height = 150.;
            Rectangle2D rect = new Rectangle2D.Double(leftX, topY, width, height);
            g2.draw(rect);
        }
}

[Fubarable]

See, SSCCEs work!

Don't forget to set the preferredSize of your drawing panel (and everything else):

    public static void main(String[] args) {
       
        JFrame frame = new JFrame();
        JPanel jpanel = new DrawPane();
        jpanel.setPreferredSize(new Dimension(400, 400)); //!! added
        JScrollPane scrollPane = new JScrollPane(jpanel);

        frame.add(scrollPane);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(true);
        frame.setPreferredSize(new Dimension(200, 200)); //!! added
        frame.pack(); //!! added
        frame.setLocationByPlatform(true);
        //frame.setSize(200,200); //!! removed
        frame.setVisible(true);

    }

[sergey]

Thank you very much!!!
It works!

[hondacodonbk]

Hey,I am have the same problem,My code draw a line with a ladge leng on a jpanel,Then I add this jpanel to a frame which smaller leng.I can scroll,but the picture of line has some problem.can You help me?
this is my main code:

/*
 * class vi du tao scroll cho ung dung ve mui ten. Khi panel chua mui ten thay doi ve be rong thi scroll se duoc tao ra de co the keo de xem
 * mui ten
 *
 */
package vd;

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

    
class Ve extends JPanel{  // jpanel se duoc add vao scrollpane
    int w,h;
    public Ve(){}
    public Ve(int w,int h){
        this.w = w;
        this.h = h;
        setSize(w,h);
        
        /*
         * In Swing a scrollpane asks its viewport child (the view, here, obj of ve) for its preferred size as
            it gathers information to layout its viewports view. If you want your component to be shown at a size other
            than the scrollpanes viewport view size you must provide the size information to the scrollpane. You can do
            this by calling setPreferredSize on the component or by overriding getPreferredSize in the component and returning the desired size
         */
        //setPreferredSize(new Dimension(w,h));
    }
    public void paintComponent(Graphics g)
    {
        Graphics2D  g1 = (Graphics2D) g;
        g1.setColor(Color.red);
             // draw a line
        g1.drawLine(getWidth()-20,50);
    }
}

public class Main
{
    public JFrame fr;
    public JScrollPane scr;
    public Ve ve;
    public Main()
    {
        int wframe = 600;
        int hframe = 400;
        
        ve = new Ve(); //wframe*2,hframe);  //*** dieu chinh wpanel se thay duoc su thay doi cua scroll
        ve.setPreferredSize(new Dimension(wframe*2,hframe));

        fr = new JFrame("Thu nghiem");
        
        // tao scroll de add jpanel vao
        scr = new JScrollPane(ve);//,JScrollPane.VERTICAL_SCROLLBAR_NEVER,JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
        scr.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);

        
        //Container contentPane = fr.getContentPane();
        //contentPane.add(scr);

        fr.add(scr);
        fr.setDefaultCloseOperation(fr.EXIT_ON_CLOSE);
        fr.setLocation(100, 100);
        //fr.setSize(wframe,hframe);
        fr.setPreferredSize(new Dimension(wframe,hframe));
        fr.pack();
        fr.setLocationByPlatform(true);
        fr.setVisible(true);
    }

    public static void main(String[] args)
    {
        Main v = new Main();
    }
}

thank you very much

[hondacodonbk]

oh,thank you for your time to my code,I solved my problem
thank a gain