Null Pointer Exception

Programming Questions

schrute

in Programming Questions • 1 year ago

Hi guys,

I'm getting a NullPointerException when I run the code below. It happens on line 3 of animalCell. What am I doing wrong here?

Textarea myTextarea;

public void run()
{
animalCell();
}

void animalCell()
{
myTextarea = controlP5.addTextarea("label1","Some text here",100,100,200,60);
myTextarea.setColorForeground(125);
myTextarea.moveTo("default");
}

Replies(5)

tfguy44

Re: Null Pointer Exception

1 year ago

What's your variable name? myTextArea, or myTextarea?

schrute

Re: Re: Null Pointer Exception

1 year ago

I must have added it above as you were commenting. They are both the same. That's what I thought it was at first.

tfguy44

Have you not defined controlP5 somewhere, perhaps by not including the right library?
Are you sure controlP5 has a addTextarea() function?
I've not used this library myself, but those are the two things I can see that might be causing it.

schrute

Re: Re: Null Pointer Exception

1 year ago

I have this at the top:

import controlP5.*;
ControlP5 controlP5;

then this in setup():

controlP5 = new ControlP5(this);

I've used the example given by controlP5 for the text area. Could it be an issue with controlP5 = new ControlP5(this); being put in the setup() function? I've tried it elsewhere but it never seems to work.

EDIT: It works if I add the addTextarea function to the controlP5 tab that it appears on. Not sure why that is but if all else fails I guess I can hide and show. That's last resort really though.

2nd EDIT: Whatever code I put in animalCell causes a null pointer exception.

schrute

Re: Null Pointer Exception

1 year ago

Solved!

It turns out run is a reserved name or something. Changed it to runButton and it works fine.

Thanks for your help.

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