NullPointerException On a Calling a Function

[nathanpc]

Hello,
I'm building a program that gets the value of a TextField, concatenate with some other Strings and then display them on a TextBox when the ScreenCommand is clicked, the problem is that it's calling a NullPointerException. My code is like this(of course it has a lot more stuff):

/* .... */
        } else if (command == submitCommand) {
            FirstPart();
            // write pre-action user code here
            switchDisplayable(null, getTextBox3());
            // write post-action user code here
        }
/* .... */

public void FirstPart() {
    String test = "";
    test = "tst" + textField.getString() + "test";
    textBox3.setString(test);
}
/* .... */

And I get this when I click the menu:

TRACE: <at java.lang.NullPointerException:   0>, Exception caught in Display class
java.lang.NullPointerException:   0
        at mp.releaser.MPReleaser.commandAction(MPReleaser.java:130)
        at javax.microedition.lcdui.Display$ChameleonTunnel.callScreenListener(), bci=46
        at com.sun.midp.chameleon.layers.SoftButtonLayer.processCommand(), bci=74
        at com.sun.midp.chameleon.layers.SoftButtonLayer.commandSelected(), bci=11
        at com.sun.midp.chameleon.layers.MenuLayer.pointerInput(), bci=188
        at com.sun.midp.chameleon.CWindow.pointerInput(), bci=88
        at javax.microedition.lcdui.Display$DisplayEventConsumerImpl.handlePointerEvent(), bci=19
        at com.sun.midp.lcdui.DisplayEventListener.process(), bci=296
        at com.sun.midp.events.EventQueue.run(), bci=179
        at java.lang.Thread.run(Thread.java:680)

What should I do to correct this?

Best Regards,
Nathan Paulino Campos

PS: Netbeans should have a NullPointerException corrector tool

[grahamhughes]

Which is line 535?

I'd guess that either textField or textBox3 is null.

Graham.

[nathanpc]

I've already corrected that null line, but see the edits on the error.

PS:
Line 130 Is the last one:

String test = null;
        test = "tst" + textField.getString() + "test";
        textBox3.setString(test);

[grahamhughes]

If line 130 is "textBox3.setString(test)", then textBox3 is null.

Graham.

[nathanpc]

What I should do to correct?

[grahamhughes]

There is a tutorial here, on creating objects.

Graham.