SDL2 crash whit InputHandler mouse motion - c++

Question

No warnings, no errors. Compile fine, but in the bottom of update function, the following lines make crash the program:
(*m_mousePosition).setX(event.motion.x);
(*m_mousePosition).setY(event.motion.y);
This is the complete code:
#include <SDL2/SDL.h>
#include <vector>
#include "Vector2D.h"
using namespace std;
#ifndef INPUTHANDLER_H
#define INPUTHANDLER_H
enum mouse_buttons{
LEFT = 0,
MIDDLE = 1,
RIGHT = 2
};
class InputHandler{
public:
static InputHandler* Instance(){
if(s_pInstance==0){
s_pInstance= new InputHandler();
}
return s_pInstance;
}
void update(){
if(event.type == SDL_MOUSEBUTTONDOWN){
if(event.button.button == SDL_BUTTON_LEFT){
m_mouseButtonStates[LEFT]=true;
}
if(event.button.button == SDL_BUTTON_MIDDLE){
m_mouseButtonStates[MIDDLE]=true;
}
if(event.button.button == SDL_BUTTON_RIGHT){
m_mouseButtonStates[RIGHT]=true;
}
}
if(event.type == SDL_MOUSEBUTTONUP){
if(event.button.button == SDL_BUTTON_LEFT){
m_mouseButtonStates[LEFT]=false;
}
if(event.button.button == SDL_BUTTON_MIDDLE){
m_mouseButtonStates[MIDDLE]=false;
}
if(event.button.button == SDL_BUTTON_RIGHT){
m_mouseButtonStates[RIGHT]=false;
}
}
if(event.type == SDL_MOUSEMOTION){
(*m_mousePosition).setX(event.motion.x);
(*m_mousePosition).setY(event.motion.y);
}
}
SDL_Event* getEvent(){
return &event;
}
void clear();
bool getMouseButtonStates(int buttonNumber){
return m_mouseButtonStates[buttonNumber];
}
Vector2D* getMousePosition(){
return m_mousePosition;
}
private:
SDL_Event event;
vector<bool> m_mouseButtonStates;
Vector2D* m_mousePosition;
InputHandler(){
for(int i=0; i<3; i++){
m_mouseButtonStates.push_back(false);
}
}
~InputHandler(){}
static InputHandler* s_pInstance;
};
typedef InputHandler TheInputHandler;
#endif /* INPUTHANDLER_H */
Maybe its a problem whit pointers, but I don't know, I can't solve
==============================NEW EDIT======================================
Now I don't use pointers, but I must initialize the Vector2D whit two parametres. I put it in the InputHandler constructor:
InputHandler::InputHandler():m_position(0,0){
for(int i=0; i<3; i++){
m_mouseButtonStates.push_back(false);
}
}
And give me the following error:
InputHandler.cpp:12:30: error: member initializer 'm_position' does not name a non-static data member or base class
InputHandler::InputHandler():m_position(0,0){
^~~~~~~~~~~~~~~
The definition of Vector2D class:
#include<math.h>
using namespace std;
#ifndef VECTOR2D_H
#define VECTOR2D_H
class Vector2D {
public:
Vector2D(float x, float y):m_x(x), m_y(y){}
float getX(){return m_x;}
float getY(){return m_y;}
void setX(float x){m_x=x;}
void setY(float y){m_y=y;}
float length(){return sqrt(m_x*m_x + m_y*m_y);}
private:
float m_x;
float m_y;
};
#endif /* VECTOR2D_H */

Answer 1

yes, the problem is "pointers" as you put it.
m_mousePosition is declared but you never assign anything to it so it is NULL/garbage.
you probably dont need to use pointers here.