f.getContentPane().add(new hellojava2(” hello, java”)); [closed]


“hello,java” should appear in f frame but it does not. hellojava2 is the program itself. i do not get error message too.”

If you are not getting any errors, I’m going to assume your program extends JFrame, since the JFrame needs a component to be added and I doubt your program extends JLabel and JPanel has no constructor with a String parameter

  • If this is the case, you should realize that the constructor JFrame(String s) only sets the title for the frame. Nothing is printed .
  • Also if this is the case, it looks like you’re trying to add a JFrame to a JFrame, which won’t work either.
  • Also if this is the case, it seems like you trying to create another JFrame f when your class is already a JFrame. No need for that.

Try something like this as a simple HelloWorld Program. All I do is add a JLabel to a JFrame

public class HelloWorld {
    public static void main(String[] args){
        SwingUtilities.invokeLater(new Runnable(){
            public void run(){
                JFrame frame = new JFrame("Hello World");
                frame.add(new JLabel("Hello, World"));

Also take some time to go over the Swing Tutorials

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