Simple java issue

[Shicky]

Basically I want to be able to call a method i.e. drawCircle in my main method, containing arguements read in through a file. Now I have my main iterating through the data fine. I also have another class called Draw extending JPanel with paintComponent so I have a background on screen. Now I could add to this from the Draw class by typing g.fillOval or whatever but I want to do it from the main as I said above?

This would mean my code would be lots tidier and allow me to have things such as fillOval(array, array[i+1) etc in my main which would be handy.

I know this is a very simple problem, im just brain dead at the moment it seems. Any way to fix this or get around it easily enough?

 

[Shicky]

//Research.java

import java.util.*;
import java.io.*;
import javax.swing.*;
import java.awt.*;


public class Research {

	public static void main(String[] args) {
		
		JFrame f = new JFrame("Circuit");
		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		Draw d = new Draw();
		f.add(d);
		f.setSize(700, 500);		
		f.setVisible(true);
		
		try
		{
			Scanner s = new Scanner(new File("C:\\Users\\Shicky\\Desktop\\sampleTestData.txt"));
			ArrayList<String> tokens = new ArrayList<String>();
			
			int z = 0;
						
			while(s.hasNext())
			{
				String str = s.nextLine();
				if( str.length() >0)
				{
					String[] p = str.split("\\s+");
					switch (str.charAt(0))
					{
						//case '*': System.out.println("ignore");
						case 'c': 
							z++; 
						    System.out.println(p[0]);
						    
						    break;
						case 'l':
						    
						
					}	
					
				}
			}
			
			System.out.println(z);	
		
			s.close();
			
		}
		catch(Exception e)
		{
			
			System.out.println("Could not open file." );
			e.printStackTrace();
		}
		
	}

}

//Draw.java

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

public class Draw extends JPanel {

	public void paintComponent(Graphics g){
		super.paintComponent(g);
		this.setBackground(Color.WHITE);
	}
			
}

*Sorry that might have been unclear, had to jump out there. Basically in my switch statement when it hits the l case I want it to draw a circle on the canvas. The co-ordinates and additional detail I want to use for labels etc comes from parts of the split string. So essentially right now I can make a circle no problem, but I must do this inside the Draw class. What I want to do is draw a circle from the main class by saying g.fillOval(p[1], [2]) etc? I realise g.fillOval wont work from main but I want to find what will

 

[Shicky]

Just out of interest, is this for the HND in computing course? I remember doing something very similar years ago.

No mate, this is for my semi-conductor research team in korea lol

 

[Shicky]

Why don't you just write drawCircleWithLabels in the draw class and call that?

d.drawCircleWithLabels(p[1],p[2])

Im not sure I understand you correctly but if so I couldn't access p from the draw class?

Essentially im wondering is there anyway to call the paintComponent/paint methods from outside the draw class i made and if not, any possible solutions anyone sees?

 

[Shicky]

That seemed to work and make sense for the most part but when I implemented it, I then had problems with Draw d = new Draw(), it wanted to match the new constructor with labels passed in or for a new constructor completely. This was my attempt but getting all sorts of errors at the moment.

import java.util.*;
import java.io.*;
import javax.swing.*;
import java.awt.*;


public class Research {

	public static void main(String[] args) {
		
		JFrame f = new JFrame("Circuit");
		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		Draw d = new Draw();
		f.add(d);
		f.setSize(700, 500);		
		f.setVisible(true);
		
		try
		{
			Scanner s = new Scanner(new File("C:\\Users\\Shicky\\Desktop\\sampleTestData.txt"));
			ArrayList<String> tokens = new ArrayList<String>();
			
			int z = 0;
						
			while(s.hasNext())
			{
				String str = s.nextLine();
				if( str.length() >0)
				{
					String[] p = str.split("\\s+");
					switch (str.charAt(0))
					{
						//case '*': System.out.println("ignore");
						case 'c': 
							z++; 
						    System.out.println(p[0]);
						    
						    break;
						case 'l':
							f.add(new Draw(p[7], p[8]));				    
						
					}	
					
				}
			}
			
			System.out.println(z);	
		
			s.close();
			
		}
		catch(Exception e)
		{
			
			System.out.println("Could not open file." );
			e.printStackTrace();
		}
		
	}

}

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

public class Draw extends JPanel {
	
	private String _coord1;
	private String _coord2;
	
	public Draw(String coord1, String coord2){
		_coord1 = coord1;
		_coord2 = coord2;		
	}

	public Draw(){
		
	}

	public void paintComponent(Graphics g){
		super.paintComponent(g);
		this.setBackground(Color.WHITE);
		
		g.setColor(Color.GREEN);
		g.drawOval(Integer.parseInt(_coord1), Integer.parseInt(_coord2), 50, 50);
		
	}	
			
}

This cant possibly be as difficult as it seems to draw a circle! Properly stressing me out now

Program runs fine till it gets to the parseInt stage i think and then I get the following errors:

Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: null
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at Draw.paintComponent(Draw.java:23)

The full length is rather long but very similar to that involving various paint stuff. Any ideas?

 

[Shicky]

Cheers for you efforts SimonCHere but it became a little muddled for me, found a solution using a Circlelist

 

[Shicky]

I wanted to 'call' everything from main just, as I have done, not have everything in the main class

 

[Shicky]

Ah I suppose, as you can see, im a dire programmer lol