Another topic from ("x" cannot be resolved to a variable)

[Joseph Soler]

I need help on a topic that is too beginner, but I can't understand why I get this error (I look for it in another topics and try to solve it, but that error keeps coming)

Help would be greatly appreciated.

import javax.swing.JOptionPane;

public class gender_and_height {
       

	public static void main(String[] args) {
		
		
		String gender="";
		
		do {
			
			gender=JOptionPane.showInputDialog("Gender? (H/M)");
		
		}while (gender.equalsIgnoreCase("H")==false && gender.equalsIgnoreCase("M")==false);
		
	String height="";
		
		do {
			
			height=JOptionPane.showInputDialog("height?");
			int height2=Integer.parseInt(height);
		
		}while (height2>=201); //the error is there: "height2 cannot be resolved to a variable " 
        	
        
        
		
   
		
	    }
	}

[Norm Radder]

why I get this error

Please copy the full text of the error message and paste it here. It has important info about the error.

[Joseph Soler]

In the code java, i put in // in where is the current error and what that say

here is the error:

"height2 cannot be resolved to a variable "

tnks for the help

[Eric Arnold]

height2 is out of the scope of the while's conditional statement. try declaring the variable outside of the do block, like this.

import javax.swing.*;

public class gender_and_height {

    public static void main(String[] args) {

        String gender;

        do {
            gender= JOptionPane.showInputDialog("Gender? (H/M)");
        }while (!gender.equalsIgnoreCase("H") && !gender.equalsIgnoreCase("M"));

        String height;
        int height2;

        do {
            height = JOptionPane.showInputDialog("height?");
            height2 = Integer.parseInt(height);
        } while (height2 >= 201); //the error is there: "height2 cannot be resolved to a variable "
    }
}

[Eric Arnold]

Here's a nice article you might consider reading, to kinda reinforce this lesson.

[Joseph Soler]

Ohhhh...

oh, now i see the problem

thanks a lot dude, for the example and the link

[Campbell Ritchie]

Welcome to the Ranch

You have got an answer, but there is lots more you should improve.

1: Only use underscores _ in identifiers when you are defining constants.

2: Capitalise all words in a ClassName. GenderAndHeight please, not gender_and_height. Look at this old document about naming.

3: Don't double‑space code. Eric Arnol has corrected that error already.

4: Never use == false or == true. Again Eric Arnold has shown you the correct way to use false values.

5: Be sure to be consistent with your indentation. Line 31 is slightly to the right of line 24. Another thing Eric Arnold corrected. Also spacing. Make sure the } after do is followed by a space.

Why are you using option panes? That is a very old‑fashioned programming style.

[Joseph Soler]

why I use panes?
because I'm still a newbie in programing in any type of language of programing :v , I use the things that I was learning before (maybe there may better options to do what I was try to write)

but, anyway, thanks a lot for the corrections about my form to programming

[Manish Pamnani]

You didn't initialized variable "height2" outside the scope of "do while" loop
rather you initialized "height2" inside "do while" loop which made it a local variable instead of global variable.
You should initialize "height2" at the beginning of "do while" loop.


Here is your corrected code:-

import javax.swing.JOptionPane;
 
public class gender_and_height {
        
 
    public static void main(String[] args) {
         
         
        String gender="";
         
        do {
             
            gender=JOptionPane.showInputDialog("Gender? (H/M)");
         
        }while (gender.equalsIgnoreCase("H")==false && gender.equalsIgnoreCase("M")==false);
         
    String height="";
    int height2;   //"height2" should be declared here.  
		 
		 
        do {
            
            height=JOptionPane.showInputDialog("height?");
            height2=Integer.parseInt(height);
			
        }while (height2>=201); //the error is there: "height2 cannot be resolved to a variable " 
          
         
         
         
    
         
        }
    }

[Campbell Ritchie]

Joseph Soler wrote:. . . I use the things that I was learning before . . .

Find out about a Scanner object. If you have a book recommending option panes, don't use it; that book is probably seriously out of date.