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copied!<p>This is more of a general programming question so the code examples I give will just be pseudo-code. I program in C++, Java, and Python so the pseudo-code is a mix of those. I am not too sure what the name of this is called so if you could give me a name for this, I can Google for more information about it I would greatly appreciate it.</p> <p>Let's say I have a class called A. In this class, I create an instance of a class called B:</p> <pre><code>class A { //instance variables classB; variable1; variable2; //instance methods instanceFunction(parameter1, parameter2) { //Do Stuff } function1(parameter1) { classB = new B(some parameters); } setVariable1(value) { variable1 = value; } getVariable2() { return variable2; } } </code></pre> <p>In class B, I want to make changes to or make use of instance variables in class A. I can do this by passing a reference to A into B. So my A::function1 would look like this:</p> <pre><code>function1(parameter1) { variable1 = new B(this, other parameters); //Python syntax: //variable1 = B(self, other parameters) } </code></pre> <p>and my class B would look like this:</p> <pre><code>class B { //instance variables parentClass; variable2; //instance methods instanceFunction(classA, other parameters) { parentClass = classA; } function1() { parentClass.setVariable1(someValue); } function2() { variable2 = parentClass.getVariable2(); } } </code></pre> <p>What other ways are there to have use of the variables in class A inside of class B?</p> <p>If the code was C++ or Java, assume all variables are private and all methods and functions are public. Also assume all variables are passed by references or a pointers.</p> <p>Edit:</p> <p>First, thanks for all the responses!</p> <p>Some clarification: </p> <p>The reason I am asking this question is I have done a good amount of Qt programming in C++ and Python. In Qt, there are signals and slots. This lets inner objects tell the outer object to do something. For example I have an object A with objects B and C inside of it. Some change happens to object B and B needs to let A and C know. So B will emit a signal. A will catch this signal and do what it needs to do. Then, A will also let C know that B emitted this signal. This way C can do what it needs to do.</p> <p>The reason I asked my question is because I was wondering how I can do something like I described without using the Qt libraries.</p> <p>Also, let's assume B "is not" an A so I can't/don't want to use inheritance. </p>

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