Issue with pointers in a state machine

[URSvAir14]

Hello All!

I am currently trying to make a state machine based on the one on http://lazyfoo.net/articles/article06/index.php and I would like some help.

One of the functions in the Gamestate class is the changeState function, which is used to switch between the current states. It's only parameter is a Gamestate pointer, which is created in the main and then modified within the function. However I am getting an error where even though the code runs and the state is switched, when it leaves the function the state is reverted. How can I solve it?

The code is below n.n
Thanks in advance

void Gamestate::changeState(Gamestate *state){
	if (nextState != currentState){ // if you need to switch state...
		switch (nextState){ // switch to the relevant state
		case STATE_MAIN_MENU:
			state = new Main_Menu();
			break;

		case STATE_BATTLE:
			state = new Battle();
			break;
		}

		currentState = nextState; // change the current state val
	}
}

[Peter87]

Note that the state pointer is passed by value to the function so the state variable inside the changeState function is a copy of the variable that you passed from main. Changing the copy will not modify the original pointer in main. Maybe you want to pass the pointer by reference?