CODEWITHSUNDEEP
javascriptjquery
styler
styler

Reputation: 16501

having trouble using setInterval and with random number generation

I'm trying to create a random quote generator. I have created a function called timer that runs another function pickQuote every 400ms but at the moment this doesn't seem to work. in pickQuote I run a function randomNumberGen that creates a random number. My problem in the randomNumberGen is that I want to have an if or if..else in place that checks whether or not the new random number is different from the current quotes[randomNumber] but i'm unsure how to do this.

Can anyone provide me with some insight on how I can achieve this?

My current effort can be viewed here: http://jsbin.com/aqinud/12/edit

Upvotes: 0

Views: 534

Answers (2)

osahyoun
osahyoun

Reputation: 5231

Perhaps something like this:

var currentNumber = -1;
function randomNumberGen() {
  var num = parseInt(Math.random() * (len) );
  if(currentNumber != num){
    currentNumber = num;
    return num;
  } else {
    return randomNumberGen();
  }
}

I noticed you had incorrectly passed 'pickQuote' to setInterval. Try wrapping the callback in an anonymous function:

function timer() {
  runQuotePicker = setInterval(function(){
    pickQuote();
  }, 1000);
}

Otherwise you're scheduling the result of pickQuote to be invoked ever x milliseconds.

Upvotes: 3

pimvdb
pimvdb

Reputation: 154908

index is not defined outside $.each. Variables in functions are not accessible outside it if you use var.

What I recommend is altering the function as follows:

function randomNumberGen() {

  //generate randomNumber based on length of array
  // round it down (parseInt is for string->number conversion)
  var thisRandomNumber = Math.floor(Math.random() * len);

  if ( randomNumber === thisRandomNumber ) {
    randomNumberGen();
  } else {
    randomNumber = thisRandomNumber;
  }

}

So, first create a random number and only if it's different from randomNumber, update it with the newly created one. Otherwise, try again.

Also, setTimeout requires a function, so don't invoke it yet:

runQuotePicker = setInterval(pickQuote, 400);

http://jsbin.com/aqinud/13/edit

Upvotes: 3

Related Questions