update sprite position with schedule function

In my game I have an animated sprite. I added box2d to my game to add gravity. now I want to update my sprite's position using the schedule function. I got it working with objective-C, but I want it to be a multiplatform game so now I'm trying it in c++.

In my init I have the following line:

this->schedule(cocos2d::SEL_SCHEDULE(View::tick(1.0f)));

and the method tick:

void View::tick(float dt) {
world->Step(dt, 10, 10);
for(b2Body *b = world->GetBodyList(); b; b=b->GetNext()) {
if(b->GetUserData() != NULL) {
}
}
}

I get the following error on the line in my init: "cannot cast from type ' void' to member pointer type 'coco2d::sel_schedule' (aka void coco2d::CCobject::*)(float)

I have no idea what to do now. I tried to google, but everyone either uses objective - c or schedule_selector (which apparently doesn't work anymore)

Thanks in advance

Solution

You should probably not be using the schedule function to update a single sprite.

In your scene class, override the virtual method for update(...):

virtual void update(float dt)
{
    CCLOG("This was called.");
    // Do updates for everything in the scene you need to call on a tick.
}

Also, override onEnter() and onExitTransitionDidStart(). In the first, call scheduleUpdate to set up your scene for automatically being called on a tick. In the second, call unscheduledUpdate (as the scene is exiting) to stop the updates.

void IntroScene::onEnter()
{
   CCScene::onEnter();
   scheduleUpdate();
}

void IntroScene::onExitTransitionDidStart()
{
   CCScene::onExitTransitionDidStart();
   unscheduleUpdate();
}

Doing it this way gives you explicit control over what gets updated when...you only have a single function called during an update cycle.

HOWEVER, if you really want to do it:

Declare your custom updater like this:

void IntroScene::myUpdate(float dt)
{
   CCLOG("Also called");
}

Schedule it like this:

schedule(schedule_selector(IntroScene::myUpdate), 1.0f);

Unschedule it like this:

unschedule(schedule_selector(IntroScene::myUpdate));

** NOTE ** As far as I know, you can only "schedule" objects derived from CCNode.

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