SFML Input system problem - input

Question

So I was porting my game engine from SDL to SFML, and now I have a problem with my input system.
Input.h
#ifndef BULLWHIP_INPUT_H
#define BULLWHIP_INPUT_H
#include
class bc_Input
{
public:
bool bm_KeyHit(sf::Key::Code key);
bool bm_KeyDown(sf::Key::Code key);
int bm_MouseX();
int bm_MouseY();
void bm_init(sf::RenderWindow app);
private:
sf::RenderWindow App;
const sf::Input& input;
};
#endif
Input.cpp
#include "Input.h"
bool bc_Input::bm_KeyDown(sf::Key::Code key)
{
return in.IsKeyDown(key)
}
bool bc_Input::bm_KeyHit(sf::Key::Code key)
{
sf::Event event;
while(App.GetEvent(event) && event.Type == sf::Event::KeyPressed)
{
switch(event.Key.Code)
{
case key: return true; break;
default:
break;
}
}
}
void bc_Input::bm_init(sf::RenderWindow app)
{
App = app;
in = App.GetInput();
}
int bc_Input::bm_MouseX()
{
return in.GetMouseX();
}
int bc_Input::bm_MouseY()
{
return in.GetMouseY();
}
I get these errors from this:
C:\c++\sdl\bullwhip\lib\Bullwhip\/Input.h:15: error: 'bc_Input::App' cannot appear in a constant-expression
C:\c++\sdl\bullwhip\lib\Bullwhip\/Input.h:15: error: '.' cannot appear in a constant-expression
C:\c++\sdl\bullwhip\lib\Bullwhip\/Input.h:15: error: a function call cannot appear in a constant-expression
C:\c++\sdl\bullwhip\lib\Bullwhip\/Input.h:15: error: ISO C++ forbids initialization of member 'input'
C:\c++\sdl\bullwhip\lib\Bullwhip\/Input.h:15: error: making 'input' static
C:\c++\sdl\bullwhip\lib\Bullwhip\/Input.h:15: error: invalid in-class initialization of static data member of non-integral type 'sf::Input&'
c:\program files (x86)\codeblocks\mingw\bin../lib/gcc/mingw32/4.4.0/../../../../include/SFML/System/NonCopyable.hpp:57: error: 'sf::NonCopyable::NonCopyable(const sf::NonCopyable&)' is private
c:\program files (x86)\codeblocks\mingw\bin../lib/gcc/mingw32/4.4.0/../../../../include/SFML/Window/Window.hpp:56: error: within this context

Answer 1

You're calling the copy constructor here:
void bc_Input::bm_init(sf::RenderWindow app)
{
App = app;
in = App.GetInput();
}
Note one of your error messages:
error: 'sf::NonCopyable::NonCopyable(const sf::NonCopyable&)
In order to avoid this problem, you should use an actual constructor for your sf::Input object along with an initialization list.
Alternatively, if you've already initialized a sf::RenderWindow in a higher subsystem (as is likely the case), simply changing your member variable App to a reference should do the trick.
//header
sf::RenderWindow& App;
...
//source
void bc_Input::bm_init(sf::RenderWindow& app)
{
App = app;
in = App.GetInput();
}