NullReferenceException

iStefan · 03/15/2011, 16:42

Alright, This **** Exception annoys me as **** , and I've got No Idea why.
I Believe I'm missing something.. Can somebody remind me what is it?
I know It's un-pro question but ermm... here we go.

Ian* · 03/15/2011, 16:46

Declare GUI.

GUI myGUI = new GUI();

iStefan · 03/15/2011, 20:28

Why "new GUI();" ?
In Program.cs I Have public static iManager GUI; // iManager is the class(form)

.Kinshi · 03/15/2011, 20:40

Classes need to be initialized.

Read some programming books to get a better grasp.

iStefan · 03/15/2011, 21:59

Quote:

Originally Posted by .Kinshi

Classes need to be initialized.

Read some programming books to get a better grasp.

Yes but Then It Throws "No Source Available" ...

Arco. · 03/17/2011, 09:55

Quote:

Originally Posted by iStefan

Yes but Then It Throws "No Source Available" ...

Read some programming books to get a better grasp.

shitboi · 03/17/2011, 10:58

Quote:

Originally Posted by iStefan

Yes but Then It Throws "No Source Available" ...

Ian already made it so clear for you. Ask yourself, do you see the declaration or even the definition for GUI somewhere in your code?

I'll give you an example, tell me what is wrong.

Code:

int main(){
    printf("%d", [B]var[/B]);
    return 0;
}

iStefan · 03/17/2011, 13:43

Quote:
Originally Posted by shitboi
Ian already made it so clear for you. Ask yourself, do you see the declaration or even the definition for GUI somewhere in your code?

I'll give you an example, tell me what is wrong.
Code:
int main(){
    printf("%d", [B]var[/B]);
    return 0;
}

Then, var isn't declared. It's the same if i do in C# . Console.WriteLine(string); lmao.
and no need to bold, I'm not so noobish, I just Dunno what am I forgettin'

shitboi · 03/17/2011, 14:39

in your first post, you have an error msg, GUI not set to an instance of an object. If GUI is not an object, how are you going to call on it's member variable/methods?

What Ian was telling you to do is declare and initialize your GUI. (alright, the syntax will be java, but it's close to C# i think you'll undertand)

Code:

public class test{
    UserDefinedClass GUI = null;

    ...
    ...  //somewhere in the class before GUI has been called, you need to perform
    GUI = new UserDefinedClass();
    ...

    public static void Write(String x){...} // where your error occurred

    public static void WriteLine( ... ){...}
}//end of class defn

if you have an object that you will be assigning reference to, i personally suggest declare it and initialize to null, and you can check if your object is null at any time to make sure things are on the right track

Ian* · 03/17/2011, 17:50

well stefan if your methods are static you dont have to initialize it, but in this case I dont think they are if you're just using your gui's properties that visual studios gives you. so you have to initialize it.

Some info on msdn.

TomasLT · 03/20/2011, 21:56

And start reading what your ide offering u. First troubleshooting tip:

YourClassName GUI = new YourClassName();

iStefan · 03/21/2011, 16:03

But I am initializing it when it starts..

Code:

   GUI = new iGUI();
            Application.Run(GUI);

shitboi · 03/21/2011, 17:32

it's better off that you load your entire code up here so that others can help you.