Accessing an object from a vector of object pointers - c++

Question

This is a bit code i'm having trouble with:
int pressedKey = event.getNativeKeyCode();
for (int i=0; i <= AllTriggerPads.size() ;i++) {
if (AllTriggerPads[i]->get_key() == pressedKey){
AllTriggerPads[i]->mBufferPlayerNode->start();
}
}
the get_key() is getting a EXC_BAD_ACCESS (Code=1, ...) Error.
I seem to have a referencing problem. I am using almost the same code in the mouseDown and the fileDrop function:
for (int i=0; i < AllTriggerPads.size() ; i++) {
if (AllTriggerPads[i]->mRect.contains(event.getPos())) {
AllTriggerPads[i]->mBufferPlayerNode->start();
}
}
This works fine!
Sooooo, i guess i am using the AllTriggerPads vector (of obj pointers) not correctly. So I CAN use AllTriggerPads[i]->mRect.contains(event.getPos())
but I CANT use AllTriggerPads[i]->get_key(). And I CANT access the value itself by AllTriggerPads[i]->key
I have tried it with AllTriggerPads.at(i) but then i get an out of range error which makes me wonder even more.
The AlltriggerPads was initialized with
vector<TriggerPad*> AllTriggerPads;
So how can I access the key member?

Answer 1

You are having an off-by-one error.
for (int i=0; i <= AllTriggerPads.size() ;i++)
replace with
for (int i=0; i < AllTriggerPads.size(); ++i)
(The ++ thing is irrelevant, it's just better practice to always use pre-increment)

Answer 2

You are trying to access an array element which doesn't exist. That's why it throws EXC_BAD_ACCESS. Change the for loop conditional to
for (int i = 0; i < AllTriggerPads.size(); ++i) {
if (AllTriggerPads[i]->get_key() == pressedKey) {
AllTriggerPads[i]->mBufferPlayerNode->start();
}
}
or if C++11 support is enabled, simplify it to
for (auto i : AllTriggerPads) {
if (i->get_key() == pressedKey) {
i->mBufferPlayerNode->start();
}
}