Android studio- Java

Question

I heard that in java Instance (non-static) methods work on objects and to invoke non static method requires to have a reference to an instance. But here in this Java(Android) code non Static method is called without creating an object inside onCreate() method and no errors. I wonder why is that?

Answer 1

Galstyan

Check this example:

public class Program
{
public static void main(String[] args) {

example1();

Program p = new Program();

p.example2();
}

private static void example1() {
System.out.println("Static method");
}

private void example2() {
System.out.println("Non-Static method");
example3();
}

private void example3() {
System.out.println("Non-Static method 1");
}
}

Here main method and example1 both are static method so you can access example1 method inside main method directly.

But you cannot access non-static method example2 inside main method directly so here you need an object.

example2 and example3 both are non-static so you can directly access example3 method inside example2 method

Answer 2

Where is code?

Answer 3

Galstyan

Both methods are in same class so you can access one method inside another method no need to create object.

Answer 4

Galstyan

main method is a static method so if you access another method inside it then you need to make it static.

A class can have different types of method static and non-static

a static method can access only static variable or static method.

Answer 5

Galstyan

In your example onCreate and myFunc both are non-static so you can access myFunc inside onCreate

Answer 6

A͢J You can’t imagine how grateful I am. Thank you very much kind man!! 🙏🏻

Answer 7

public class MainActivity extends AppCompactActivity{

@Override
public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

myFunc();
}

public void myFunc(){

// code here

}

}

Answer 8

A͢J Help to understand whats going on pleasse…

Answer 9

Only calling the function inside the onCreate function confused me but now it's clear very clear!!!
Thank you very much! You saved me! A͢J

Answer 10

A͢J
so what about java main function?

Answer 11

A͢J

If u wanna call a function inside the main function then your function to hafta be static inside the same class

Answer 12

A͢J its work only for main function? not in onCreate()?