Passing variables between classes, in Java!

Question

I am a beginner learning Java. I have two classes,

public class myClassA {
    //It contains the main function

    yourClass tc = new yourClass();

    .... many codes...

    public void printVariable()
    {
        // print here
    }

}


class yourClass {

    void I_AM_a_button_press()  // function
    {
        // I want to call printVariable() in myClassA here, But how?
    }
}

How can I call a method defined in one class from another?

Answer 1

You need to pass in an instance of myClassA into a constructor for yourClass, and store a reference to it.

class yourClass {

    private myClassA classAInstance;

    public yourClass(myClassA a)
    {
        classAInstance = a;
    }

    void I_AM_a_button_press()  // function
    {
        classAInstance.printVariable();
    }
}