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JavaScript Object-Oriented JavaScript: Challenge Making the Game Interactive moveLeft() and moveRight() Methods Solution

Uncaught TypeError: this.activePlayer.activeToken.moveRight is not a function at Game.handleKeydown

Everything goes ok until a press the left arrow and then an uncaught typeError appears: Game.js:57 Uncaught TypeError: this.activePlayer.activeToken.moveRight is not a function at Game.handleKeydown (Game.js:57) at HTMLDocument.<anonymous> (app.js:15) I don't know why it fives me this error. Can anyone help please?

3 Answers

Steven Parker
Steven Parker
229,967 Points

A common generic cause of this error is trying to access an attribute/method on a null or undefined variable. Check the value of "activePlayer" or "activePlayer.activeToken".

If you'd like more specific help, make a snapshot of your workspace and post the link to it here.

Thanks Steven, I'll take a look and get it working. :)

In my case I got this error because I forgot to save the Token.js file before I ran the code - so literally that function didn't exist! Duh! Took me a couple minutes to figure out why that wasn't working.