Getting random arrays not working?

Question

I'm trying to create a simple JS that will get random arrays and post them via div container. Here's what I have so far, now keep in mind I'm horrible with JS.

function timedMsg() {
    currMsg++;
    document.getElementById('timedMsgDiv').innerHTML = msgArr[currMsg % msgArr.length];
};

function init() {
    currMsg = -1;
    msgArr = Array('Computer.', 'Uploading', 'Random');
    timedMsg();
    var t = setInterval("timedMsg()", 50);
};

window.onload = init();

It only gets 'Computer' and then does not flip through them randomly or loop or anything. Any reason why? Here's my JSFiddle: http://jsfiddle.net/R8SYf/

Some things don't look right, in your code and fiddle. Fixed http://jsfiddle.net/R8SYf/11/ — elclanrs, Feb 02 '14 at 00:21

score 2 · Accepted Answer · answered Feb 02 '14 at 00:20

2

Pass the function name to setInterval(), like this:

var t = setInterval(timedMsg, 2000);

http://jsfiddle.net/R8SYf/6/

answered Feb 02 '14 at 00:20

Niklas

13,005
23
79
119

1

`setInterval(timedMsg, 2000);` – elclanrs Feb 02 '14 at 00:21
@elclanrs - Yeah, that's shorter and nice! – Niklas Feb 02 '14 at 00:22
Thank you. It worked. Will set answer once I'm able to. – ErraticFox Feb 02 '14 at 00:24
But this is not the real issue though. The real problem is how the fiddle is set up, OP has to load scripts in head `No wrap - `, and assign a function to the load event (not the returned value) and it should work http://jsfiddle.net/R8SYf/13/ – elclanrs Feb 02 '14 at 00:25
@elclanrs what do you mean? – ErraticFox Feb 02 '14 at 00:33
This is good practice but you have other problems in the code. This is your code and fiddle fixed, just go line by line you'll see the difference. http://jsfiddle.net/R8SYf/11/ – elclanrs Feb 02 '14 at 00:35

score 1 · Answer 2 · answered Feb 02 '14 at 00:41

There are a few problems in your code:

1) When you pass a string to setInterval you trigger eval and your function is run in the global context, you don't want this. To fix it simply pass a reference to the function; rebember functions are objects too:

var t = setInterval(timedMsg, 2000);

2) The window.load event expects a function but you're assigning the returned value of the init function which is undefined. Like in the case above you need to pass a function object, not execute the function:

window.onload = init;

3) Your fiddle is set-up to load the code in the onLoad event, but you're assigning your own function. You need to change the behavior to No wrap - in <head>.

4) Although is works, using the Array constructor to create arrays is not good practice. Simply use the literal syntax:

msgArr = ['Computer.', 'Uploading', 'Random'];

Fixed http://jsfiddle.net/R8SYf/11/

How could I get this randomized? By the way, I'll be adding a lot more. — ErraticFox, Feb 02 '14 at 00:45
Shuffle your array first, see here http://stackoverflow.com/questions/6274339/how-can-i-shuffle-an-array-in-javascript — elclanrs, Feb 02 '14 at 00:46
I understood a little bit, but would not know how to modify it to work inside my script. — ErraticFox, Feb 02 '14 at 00:52

Getting random arrays not working?

2 Answers2