Display text to a label from another class - JFrame

Question

I have a GUI screen, and it has a label in it. I now want to set the label with a text as i have shown in below (Test). But it\'s not getting updated. I think t

Answer 1

Change the mainScreen() function to

public  void mainScreen() {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

remaining code is same

Answer 2

Add a method to your FrameTest

public String readLabel(){
       return this.lblLabel.getText();
}

Answer 3

In your mainScreen() you create a new FrameTest that is distinct from the one you create in the main routine, so it's actually changing the text, of the invisible frame. Try this instead:

private FrameTest frame = this;

public  void mainScreen() {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
                frame.setVisible(true);
        }
    });
}

Or simply:

public  void mainScreen() {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
                setVisible(true);
        }
    });
}

Answer 4

Replace the try block with;

            try {
                setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }

Everything works!

Answer 5

The way you use your code does not trigger a repaint of your frame or label. In Swing you can change many Gui Objects, but they are only redrawn in a single batch when requested. The most usual case when a repaint occurs automatically, is after you return from an event handler. (E.g. a button click or key press)