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Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,252 Points

OOP JavaScript Course: PlayList example

I'm about 5 minutes into the video but I haven't been following it correctly and thus I've just spent the last hour debugging it and this is my snapshot so far.


If you fork it out, you can see that I'm almost there but I keep getting NaNNaN where the titles of the songs should be. I'm out of ideas I'm afraid, any idea what could be up?

1 Answer

Grace Kelly
Grace Kelly
33,990 Points

Hi Jonathan, I notice in your song.js file you have "=+" instead of "+=" when adding to the htmlString variable, I would start by rectifying that:

if(this.isPlaying) {
    htmlString += ' class="current"'; //only add class of current if the song is playing
  htmlString += '>'; //use += 
  htmlString += this.title;
  htmlString += ' - ';
  htmlString += this.artist;
  htmlString += '<span class="duration">';
  htmlString += this.duration; 
  htmlString += '</span></li>'; 

  return htmlString;  //return string to function

Hope that helps!!

Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,252 Points

Hi Grace,

Sorry it took so long for me to respond but yup, you were right! I thought i'd fixed that before but it's such a simple thing to miss ;)