SFML 2.0 c++ sprite in array/vector - c++

Question

I have this in my file blocks.h:
#include <vector>
class Blocks{
public:
string files_name[4];
vector < Sprite > sprites;
void load(){
for(int i=0;i<=sizeof(files_name);i++){
Texture my_texture;
my_texture.loadFromFile(this->files_name[i]);
sprites[i].setTexture( my_texture );
}
}
Blocks(){
this->files_name[0] = "wall.png";
this->files_name[1] = "floor.png";
this->files_name[2] = "live.png";
this->files_name[3] = "coins.png";
this->load();
}
void show(int id, int X, int Y){
sprites[id].setPosition(X, Y);
window.draw(sprites[id]);
}
};
I have no errors, but my game crashed. I think, the problem is in the line which reads sprites[i].setTexture(...)
I only have the message: Process terminated with status -1073741819 (0 minutes, 2 seconds)
My IDE is Code::Blocks 10.05, and I have Windows 8.
Of course, in the file main.cpp, I have defined the window:
RenderWindow window( VideoMode(920, 640, 32 ), "Game" );
#include "blocks.h"
Blocks BLOCKS;
----UPDATE:
Ok, now it's not crashing, thanks! But, now I can't see textures! I read the post by Benjamin Lindley and I added a new vector with textures. My code looks like this now:
const int arraySize = 4;
string files_name[4];
vector < Sprite > sprites;
vector < Texture > textures;
and, in load(), I have:
for(int i = 0; i < arraySize; i++){
Texture new_texture;
new_texture.loadFromFile(this->files_name[i]);
textures.push_back(new_texture);
sprites[i].setTexture(textures[i]);
and then it crashes again!
---UPDATE: Now I have again changed my code and I don't have a crash, but my textures are white squares. My texture live.png works, but the other textures are white! Here's my new code:
Sprite new_sprite;
new_sprite.setTexture(textures[i]);
sprites.push_back(new_sprite);

Answer 1

The problem is this line:
for(int i=0;i<=sizeof(files_name);i++){
If you print out the value of sizeof(files_name), you will find that it is 16 instead of 4! Don't use sizeof here. Also, don't use <= here, since even if you had replaced sizeof(files_name) with 4, you would have tried to access files_name[4], which would also give you an error.
Instead you could use:
const int arraySize = 4;
string files_name[arraySize];
...
for(int i = 0; i < arraySize; i++)
or something of that sort.
Also, hopefully you initialize sprites at some point. You need to fill your vector with Sprites (with something like sprites.push_back(mySprite)) before you call load().

Answer 2

SFML sprites store their associated textures by pointer. The textures you are creating are local to the loop, and so are destroyed at the end of each iteration, thereby invalidating the pointer in the sprite. You need to keep your textures alive for the duration of whatever sprite uses them.
Also, your sprites vector has no elements, you need to either specify a size, or use push_back in your loop.
Also, as Scott pointed out, sizeof(files_name) is not the appropriate terminating value for your loop, since that gives you sizeof(string) * number of elements in the array. You only want the number of elements in the array.

Answer 3

Ok, it works only in two loop: Thanks for helping :)
vector < Sprite > sprites;
vector < Texture > tekstures;
and:
for(int i = 0; i < arraySize; i++){
Texture new_texture;
new_texture.loadFromFile(this->files_name[i]);
tekstures.push_back(new_texture);
}
for(int i = 0; i < arraySize; i++){
Sprite new_sprite;
new_sprite.setTexture(tekstures[i]);
sprites.push_back(new_sprite);
}
and in one loop it doesn't work, i have white textures:
for(int i = 0; i < arraySize; i++){
Texture new_texture;
new_texture.loadFromFile(this->files_name[i]);
tekstures.push_back(new_texture);
Sprite new_sprite;
new_sprite.setTexture(tekstures[i]);
sprites.push_back(new_sprite);
}
Greetings !