Cannot access protected member in base class [duplicate]

Answer 1

protected does mean that the derived class can access it, however, the derived class can access the property of it's own instance. In your example, you can access this.m_Title since that belongs to the instance itself, but you are attempting to access the protected member of another instance (i.e. the instance in the list m_SubMenuItems).

You need getter and setter methods to access it the way you're trying to.

Hopefully this makes it clearer:

class Foo {
    protected int x;

    public void setX(int x) {
        this.x = x;
    }
}

class Bar : Foo {
    Foo myFoo = new Foo();

    public void someMethod() {
        this.x = 5;    // valid. You are accessing your own variable
        myFoo.x = 5;   // invalid. You are attempting to access the protected
                       // property externally
        myFoo.setX(5); // valid. Using a public setter
    }
}