How do I make a text fields horizontal and non-editable?

Question

I have this applet that will add 2 numbers together and display their sum in a third text box.

https://pastebin.com/4ga1brD1

I want the text boxes to be arranged horizontally but more importantly I need the third text box to be uneditable.

import java.applet.*;

import java.awt.*;
import java.awt.event.*;
public class Question extends Applet implements ActionListener
{
   TextField firstNum, secondNum, resultNum;
   public Question()
   {                      
      setLayout(new GridLayout(3, 2, 10, 15));  
      setBackground(Color.cyan);
 
      firstNum = new TextField(15);
      secondNum = new TextField(15);
      resultNum = new TextField(15);
 
      secondNum.addActionListener(this);
 
      add(new Label("Enter First Number"));  
      add(firstNum);
      add(new Label("Enter Second Number")); 
      add(secondNum);
      add(new Label("S U M"));               
      add(resultNum);
   }
   public void actionPerformed(ActionEvent e)
   {                        
      String str1 = firstNum.getText();
      double fn = Double.parseDouble(str1);
      double sn = Double.parseDouble(secondNum.getText());
 
      resultNum.setText("Sum is " + (fn+sn));
   }
}

Answer 1

To arrange your TextField components horizontally, don't add them directly to the Applet. Instead, create a Panel, give it a FlowLayout and add your TextField components to the Panel. Then you can add the Panel directly to your Applet. Make sure your Applet is wide enough to fit all three boxes side by side or the layout will stack the third box under the first one.

Note: I would test this for you, but no browser has supported Applets for at least five years.

To make the third TextField uneditable, you want to use the setEnabled() method. setEditable() would be the way to accomplish the same thing if you were using JTextField, as opposed to the simple AWT TextField that you're using. You should get in the habit of looking at the official documentation, where the answer is readily found.

resultNum.setEnabled(false);

Bear in mind that a disabled box will appear greyed out, which may be visually unappealing. The solution is to convert to Java Swing, which will allow you to use setEditable, which simply prevents your user from clicking into the box without changing the appearance. Swing would also allow you to use layout managers with much more sophistication and flexibility.