Cocos2D-X Layer::init() gets stuck when waiting for Leaderboard Service

Question

I'm trying to integrate App42 Leaderboard Service to my Cocos2D-X Game. The core functionality (Sending Scores to Server and retrieving them, just the way shown on the App42 site...) is working fine.

Now i want to visualize my leaderboard data using a CCTableView.

So I got a Leaderboard class (inherited from CCLayer) and am doing something like this :

bool Leaderboard::init() {
    ...
    // Initialize and send App42 Scoreboard API call
    App42API::Initialize(API_KEY, SECRET_KEY);
    ScoreBoardService *scoreBoardService = App42API::BuildScoreBoardService();
    scoreBoardService->GetTopNRankers(gameName,MAX_SCORES, this,app42callfuncND_selector(Leaderboard::onGetTopNRankings));

    // responseArrived is boolean, indicates if onGetTopRankings was called
    while(!responseArrived);

    CCTableView* tableView = CCTableView::create(this, CCSizeMake(400, 100));
    tableView->setDirection(kCCScrollViewDirectionVertical);
    tableView->setPosition(winSize.width/3 , winSize.height/2);
    tableView->setDelegate(this);
    tableView->setVerticalFillOrder(kCCTableViewFillTopDown);
    this->addChild(tableView,5);
    tableView->reloadData();

    return true;
}



void HelloWorld::onGetTopNRankings(App42CallBack *sender, void *response){

    App42GameResponse *scoreResponse = (App42GameResponse*)response;

    if (scoreResponse->isSuccess)
    {
        // Save User scores to Array
        responseScores = scoreResponse->scores;
    }
    else
    {
        printf("\nerrordetails:%s",scoreResponse->errorDetails.c_str());
        printf("\nerrorMessage:%s",scoreResponse->errorMessage.c_str());
        printf("\nappErrorCode:%d",scoreResponse->appErrorCode);
        printf("\nhttpErrorCode:%d",scoreResponse->httpErrorCode);
    }
    // Response Data is saved, or Error occured, go back to init()
    responseArrived = true; 
}

So as you see, I am waiting for onGetTopNRankings to get called, because the data for my TableView would be empty else. But what happens is, that the I can't get back to init() when onGetTopNRankings returns, it gets stuck.

So anybody got an idea why i can't return to Leaderboard::init() or got any good idea to solve this in any other way, I am open for each suggestion ?

Answer 1

while(!responseArrived);

This blocks the thread (endless loop). You need to fill your table view in the callback method when you have actual data. It will be empty until then. That's something your app's design has to deal with. For instance you could display a "loading" animation in the meantime, with a cancel button on it.

Answer 2

I tested your code and it is working fine in my App42Cocos2dXSample

The only possible reason for the issue you are getting is the owner class name of callback method in your code snippet.

scoreBoardService->GetTopNRankers(gameName,MAX_SCORES, this,app42callfuncND_selector(Leaderboard::onGetTopNRankings));

In the above statement, onGetTopNRankings belong to the class Leaderboard, but while defining the callback method, it belongs to the class Helloworld:

void HelloWorld::onGetTopNRankings(App42CallBack *sender, void *response){

So, try changing the class name from Helloworld to Leaderboard in the above statement. I hope it will work.