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2D Javascript Array TypeError

[EDIT] Full application available at: http://bit.ly/1CGZzym
I'm receiving the error:
Uncaught TypeError: Cannot set property '0' of undefined
with the following code. I believe it is due to my not declaring the child array of the 2D array properly but I am really confused as to where I should be declaring this. Any ideas would be excellent.
// Create an array for the tiles we're about to draw
var tileArray = []
is declared out side of the function.
I assume it is because I am trying to create child elements within each [col] so I guess I need to declare each col number somewhere but nothing I attempt seems to be working.
function drawGrid()
{
// Draw diamond grid
var col = 0;
var row = 0;
topTileX = (viewWidth/2);
topTileY = 0;
var nextX = 0;
var nextY = 0;
var getCols = 0;
while (topTileX > -1)
{
tileArray[col][row] = new DiamondTile(topTileX, topTileY, tileWidth, true, col, row);
tileArray[col][row].draw();
while (tileArray[col][row].xPos + tileArray[col][row].tileWidth < (viewWidth) + tileWidth)
{
col++;
nextX = tileArray[col-1][row].xPos + tileArray[col-1][row].tileWidth / 2;
nextY = tileArray[col-1][row].yPos + tileArray[col-1][row].tileHeight / 2;
tileArray[col][row] = new DiamondTile(nextX, nextY, tileWidth, true, col, row);
tileArray[col][row].draw();
if (col == getCols)
{
break;
}
}
row++;
getCols = col;
col = 0;
topTileX = topTileX - tileWidth/2;
topTileY = topTileY + tileHeight/2;
}
};
For the purpose of demonstration, the DiamondTile function is as follows:
function DiamondTile(xPos,yPos,width,interactive,myCol,myRow)
{
// Set x and y position for this sprite
this.xPos = xPos;
this.yPos = yPos;
this.myRow = myRow;
this.myCol = myCol;
// Used for AI pathfinding
this.isObstacle = false;
this.isStart = false;
this.isEnd = false;
this.gValue = 0;
this.hValue = 0;
this.fCost = 0;
this.tileWidth = width;
this.tileHeight = this.tileWidth/2;
var self = this;
// Create sprite
this.spriteObj = new PIXI.Sprite(grass);
this.spriteObj.interactive = interactive;
this.spriteObj.anchor = new PIXI.Point(0.5,0);
this.spriteObj.hitArea = new PIXI.Polygon([
new PIXI.Point(0,0),
new PIXI.Point(100,50),
new PIXI.Point(0,100),
new PIXI.Point(-100,50)
]);
this.spriteObj.mouseover = function()
{
if (self.spriteObj.tint == 0xFFFFFF)
{
self.spriteObj.tint = 0xA7E846;
}
text2.setText(self.myCol + "," + self.myRow + " Start: " + self.isStart);
}
this.spriteObj.mouseout = function()
{
if (self.spriteObj.tint == 0xA7E846)
{
self.spriteObj.tint = 0xFFFFFF;
}
}
this.spriteObj.click = function()
{
if (startStage === true)
{
startStage = false;
self.isStart = true;
self.spriteObj.tint = 0x1AFF00;
text.setText("Now select an end point");
endStage = true;
return true;
}
if (endStage === true)
{
endStage = false;
self.isEnd = true;
self.spriteObj.tint = 0xFF0000;
text.setText("Now place some obstacles");
obsStage = true;
return true;
}
if (obsStage ===true)
{
self.isObstacle = true;
self.spriteObj.tint = 0x3B3B3B;
text.setText("Press 'C' to calculate path");
return true;
}
}
};

That is a multi-dimensional array and you have not initialized the first dimension array correctly. In the while loop you have to initialize the first dimension to be able to access a second dimension element with an index:
while (topTileX > -1)
{
if (tileArray[col] == null)
tileArray[col] = [];
tileArray[col][row] = new DiamondTile(topTileX, topTileY, tileWidth, true, col, row);
tileArray[col][row].draw();
// omitted other code for brevity
}
Javascript arrays are dynamic and it's enough to initialize the first dimension array elements in this case. You don't have to initialize the individual items in the second dimension.
Update: here is a fiddle with working code http://jsfiddle.net/0qbq0fts/2/
In addition your semantics is wrong. By the book, the first dimension of a 2-dimensional array should be rows, and the second dimension should be columns.

You have to explicit create the elements representing the second dimension, e.g.:
function make2DArray(rows, cols) {
var r = Array(rows);
for (var i = 0; i < rows; ++i) {
r[i] = Array(cols);
}
return r;
}
If you don't know in advance how many columns, just use this:
function make2DArray(rows) {
var r = Array(rows);
for (var i = 0; i < rows; ++i) {
r[i] = [];
}
return r;
}
The individual rows can each have independent lengths, and will grow as you add values to them.
Similarly, if you just need to add a new (empty) row, you can just do:
tileArray.push([]);

This should probably me a comment, but SO has crashed on my side. JavaScript might be throwing an exception on your stated line, but the problem may be with the 'DiamondTile' function.

Javascript Loop not working with local storage

I have code that loads the variables and turns them into numbers, I can do math with these, and can display them on page, but i have functions, that worked before the loading was added, that use these variables to automatically add 1 to the variables. I have a loop that runs this automatic addition. however the loop does not seem to be working after the addition of the loading.
if(typeof(Storage)!=="undefined") {
var hotdogs = parseInt(localStorage.getItem('hotdogs'), 10);
var bread = parseInt(localStorage.getItem('bread'), 10);
var hotdog = parseInt(localStorage.getItem('hotdog'), 10);
var sauce = parseInt(localStorage.getItem('sauce'), 10);
var bakeries = parseInt(localStorage.getItem('bakeries'), 10);
var butchers = parseInt(localStorage.getItem('butchers'), 10);
var sauceries = parseInt(localStorage.getItem('sauceries'), 10);
}
else {
var hotdogs = 0;
var bread = 0;
var hotdog = 0;
var sauce = 0;
var bakeries = 0;
var butchers = 0;
var sauceries = 0;
}
function buyBakery(){
var bakeryCost = Math.floor(20 * Math.pow(1.05,bakeries));
if(hotdogs >= bakeryCost){
bakeries = bakeries + 1;
hotdogs = hotdogs - bakeryCost;
document.getElementById('bakeries').innerHTML = bakeries;
document.getElementById('hotdogs').innerHTML = hotdogs;
};
var nextCostBakery = Math.floor(20 * Math.pow(1.05,bakeries));
document.getElementById('bakerycost').innerHTML = nextCostBakery;
};
(function loop(timer) {
setTimeout(function() {
breadClick(bakeries);
hotdogClick(butchers);
sauceClick(sauceries);
customers(custom);
loop(1000);
}, timer)
})(1000)

For starters you don't appear to be calling the buyBakery() method within your loop.
Secondly, even though 'Storage' is defined the item you are looking for may not be on it.in that case it'll return null instead and parseInt() will convert into NaN(Not a Number)
also make sure the other functions you are calling within the loop are exist and not throwing any errors.use the web console for that.
you might wanna consider saving values back on localStorage (if you are not already doing that) so you can get it later. I've added function to do that on my example.
Try some thing like this.
function loadFromLS(item) {
var ret = 0;
if (typeof (Storage) === 'undefined') {
return ret;
}
if (null === (ret = localStorage.getItem(item))) {
ret = 0;
}
return parseInt(ret, 10);
}
function saveToLS(item, val) {
if (typeof (Storage) === 'undefined') {
return;
}
localStorage[item] = val;
}
var hotdogs = loadFromLS('hotdogs');
var bread = loadFromLS('bread');
var hotdog = loadFromLS('hotdog');
var sauce = loadFromLS('sauce');
var bakeries = loadFromLS('bakeries');
var butchers = loadFromLS('butchers');
var sauceries = loadFromLS('sauceries');
function buyBakery() {
var bakeryCost = Math.floor(20 * Math.pow(1.05, bakeries));
if (hotdogs <= bakeryCost) {
bakeries = bakeries + 1;
hotdogs = hotdogs - bakeryCost;
document.getElementById('bakeries') .innerHTML = bakeries;
document.getElementById('hotdogs').innerHTML = hotdogs;
};
var nextCostBakery = Math.floor(20 * Math.pow(1.05, bakeries));
document.getElementById('bakerycost') .innerHTML = nextCostBakery;
};
(function loop(timer) {
setTimeout(function () {
breadClick(bakeries);
hotdogClick(butchers);
sauceClick(sauceries);
customers(custom);
loop(1000);
}, timer)
}) (1000)

Extending a class in javascript

I have two almost identically classes written in js. I would like to make one of them extend the other one, in order to have less code. I'm a novice in javascript and I need a little help to make this.
I'm posting the classes here. Can anybody help?
//============================================================================================================================================
//Class1==================================================================================================================================
//============================================================================================================================================
function Class1(config){
var targetObj;
var copycanvas = null;
var copy = null;
var outputcanvas = null;
var draw = null;
var direction = config.direction || "lr";
var TILE_WIDTH = config.tileWidth || 100;
var TILE_HEIGHT = config.tileHeight || 100;
var SOURCERECT = {x:0, y:0, width:0, height:0};
var interval;
var tiles2 = [];
var cols = 0;
var rows = 0;
createTiles = function(){
tiles = [];
tiles2 = [];
var y=0;
while(y < SOURCERECT.height){
var x=0;
cols = 0;
while(x < SOURCERECT.width){
cols++;
x += TILE_WIDTH;
}
rows++;
y += TILE_HEIGHT;
}
var i, j;
if (direction == "tl"){
for (i = 0; i < rows; i++)
for (j = 0; j < cols; j++){
x = j * TILE_WIDTH;
y = i * TILE_HEIGHT;
var tile = new Tile();
tile.imageX = x;
tile.imageY = y;
tiles2.push(tile);
}
}
arrangeSquares();
};
arrangeSquares = function(){
var i, j, k;
var M, N;
M = rows;
N = cols;
i = j = 0;
var cnt = 0;
for (i = 0; i < N + M - 1; i++)
for (j = 0; j <= i; j++)
if (j < M && (i - j) < N){
tiles.push(tiles2[j * N + (i - j)]);
}
}
processFrame = function(){
copycanvas.width = outputcanvas.width = targetObj.width;
copycanvas.height = outputcanvas.height = targetObj.height;
copy.drawImage(targetObj, 0, 0, targetObj.width, targetObj.height);
for(var i=0; i < tiles.length; i++) {
var tile = tiles[i];
tile.alpha += 0.05;
var TH = Math.max(0, Math.min(TILE_HEIGHT, targetObj.height - tile.imageY));
var TW = Math.max(0, Math.min(TILE_WIDTH, targetObj.width - tile.imageX));
draw.save();
draw.translate(tile.imageX, tile.imageY);
draw.globalAlpha = Math.max(0, tile.alpha);
draw.drawImage(copycanvas, tile.imageX, tile.imageY, TW, TH, 0, 0, TW, TH);
draw.restore();
}
var ok = true;
for (i = 0; i < tiles.length; i++) {
if (tiles[i].alpha < 1) {
ok = false;
break;
}
}
if (ok)
{
clearInterval(interval);
showComplete();
}
};
function showComplete() {
$target.trigger("showComplete");
$img.show();
$(copycanvas).remove();
$(outputcanvas).remove();
if ($hideTarget)
$hideTarget.hide();
};
this.hide = function(target) {
};
var $target = null;
var $img = null;
var $hideTarget = null;
this.show = function(target, hideTarget){
$target = $("#" + target).show();
align($target);
if (hideTarget != undefined) {
$target.before($hideTarget = $("#" + hideTarget).show());
align($hideTarget);
}
$img = $("#" + target + " > img").filter(":first").hide();
$("<canvas/>").attr("id", "sourcecopy")
.css("position", "absolute")
.appendTo($target)
.hide();
copycanvas = document.getElementById("sourcecopy");
copy = copycanvas.getContext('2d');
$("<canvas/>").attr("id", "output")
.css("position", "absolute")
.appendTo($target);
outputcanvas = document.getElementById("output");
draw = outputcanvas.getContext('2d');
targetObj = document.getElementById($img.attr("id"));
clearInterval(interval);
SOURCERECT = {x:0, y:0, width: targetObj.width, height: targetObj.height};
createTiles();
for(var i=0; i<tiles.length; i++){
var tile = tiles[i];
tile.alpha = 0 - (i * (2 / tiles.length));
}
var intervalDelay = (config.duration * 1000) / (40 + rows + cols);
interval = setInterval(function() { processFrame(); }, intervalDelay);
};
function Tile(){
this.alpha = 1;
this.imageX = 0;
this.imageY = 0;
};
};
//============================================================================================================================================
//Class2===================================================================================================================================
//============================================================================================================================================
function Class2(config){
var targetObj;
var copycanvas = null;
var copy = null;
var outputcanvas = null;
var draw = null;
var direction = config.direction || "lr";
var TILE_WIDTH = config.barWidth || 50;
var TILE_HEIGHT = 100;
var SOURCERECT = {x:0, y:0, width:0, height:0};
var interval;
var tiles = [];
createTiles = function(){
tiles = [];
var y=0;
while(y < SOURCERECT.height){
var x=0;
while(x < SOURCERECT.width){
var tile = new Tile();
tile.imageX = x;
tile.imageY = y;
tiles.push(tile);
x += TILE_WIDTH;
}
y += TILE_HEIGHT;
}
};
processFrame = function(){
copycanvas.width = outputcanvas.width = targetObj.width;
copycanvas.height = outputcanvas.height = targetObj.height;
copy.drawImage(targetObj, 0, 0, targetObj.width, targetObj.height);
for(var i=0; i < tiles.length; i++) {
var tile = tiles[i];
tile.alpha += 0.05;
var TH = Math.max(0, Math.min(TILE_HEIGHT, targetObj.height - tile.imageY));
var TW = Math.max(0, Math.min(TILE_WIDTH, targetObj.width - tile.imageX));
draw.save();
draw.translate(tile.imageX, tile.imageY);
draw.globalAlpha = Math.max(0, tile.alpha);
draw.drawImage(copycanvas, tile.imageX, tile.imageY, TW, TH, 0, 0, TW, TH);
draw.restore();
}
var ok = true;
for (i = 0; i < tiles.length; i++) {
if (tiles[i].alpha < 1) {
ok = false;
break;
}
}
if (ok)
{
clearInterval(interval);
showComplete();
}
};
function showComplete() {
$target.trigger("showComplete");
$img.show();
$(copycanvas).remove();
$(outputcanvas).remove();
if ($hideTarget)
$hideTarget.hide();
};
this.hide = function(target) {
};
var $target = null;
var $img = null;
var $hideTarget = null;
this.show = function(target, hideTarget){
$target = $("#" + target).show();
align($target);
if (hideTarget != undefined) {
$target.before($hideTarget = $("#" + hideTarget).show());
align($hideTarget);
}
$img = $("#" + target + " > img").filter(":first").hide();
$("<canvas/>").attr("id", "sourcecopy")
.css("position", "absolute")
.appendTo($target)
.hide();
copycanvas = document.getElementById("sourcecopy");
copy = copycanvas.getContext('2d');
$("<canvas/>").attr("id", "output")
.css("position", "absolute")
.appendTo($target);
outputcanvas = document.getElementById("output");
draw = outputcanvas.getContext('2d');
targetObj = document.getElementById($img.attr("id"));
clearInterval(interval);
if (direction == "tb" || direction == "bt")
{
TILE_WIDTH = targetObj.width;
TILE_HEIGHT = config.barWidth;
}
else
{
TILE_WIDTH = config.barWidth;
TILE_HEIGHT = targetObj.height;
}
SOURCERECT = {x:0, y:0, width: targetObj.width, height: targetObj.height};
createTiles();
if (direction == "lr" || direction == "tb")
{
for(var i=0; i<tiles.length; i++){
var tile = tiles[i];
tile.alpha = 0 - (i * (1 / tiles.length));
}
}
else
{
for(var i=tiles.length - 1; i >= 0 ; i--){
var tile = tiles[i];
tile.alpha = 0 - ((tiles.length - i - 1) * (2 / tiles.length));
}
}
var intervalDelay = (config.duration * 1000) / (40 + tiles.length);
interval = setInterval(function() { processFrame(); }, intervalDelay);
};
function Tile(){
this.alpha = 1;
this.imageX = 0;
this.imageY = 0;
};
};

Try declaring the class like this.
var theClass = function theClass() {
....
to extend this class you can use the prototype method:
theClass.prototype.newMethodName = function () {
....

You have a couple of choices. You can isolate the common functionality into a third object that Class1 and Class2 share (aggregation), or you can actually create a hierarchy of objects (inheritance). I'll talk about inheritance here.
JavaScript doesn't have classes, it's a prototypical language. An object instance is "backed" by a prototype object. If you ask the instance for a property it doesn't have (and functions are attached to objects as properties), the JavaScript interpreter checks the prototype behind the object to see if it has the property (and if not, the prototype behind that object, etc., etc.). This is how prototypical inheritance works.
JavaScript is an unusual prototypical language in that, until recently, there was no way to create an object and assign its prototype directly; you had to do it through constructor functions. If you're using class-based terminology, you're probably going to be more comfortable with constructor functions anyway. :-)
Here's a basic inheritance setup (this is not how I would actually do this, more on that below):
// Constructs an Vehicle instance
function Vehicle(owner) {
this.owner = owner;
}
// Who's this Vehicle's owner?
Vehicle.prototype.getOwner = function() {
return this.owner;
};
// Constructs a Car instance
function Car(owner) {
// Call super's initialization
Vehicle.call(this, owner);
// Our init
this.wheels = 4;
}
// Assign the object that will "back" all Car instances,
// then fix up the `constructor` property on it (otherwise
// `instanceof` breaks).
Car.prototype = new Vehicle();
Car.prototype.constructor = Car;
// A function that drives the car
Car.prototype.drive = function() {
};
Now we can use Car and get the features of Vehicle:
var c = new Car("T.J.");
alert(c.getOwner()); // "T.J.", retrived via Vehicle.prototype.getOwner
The above is a bit awkward and it has a couple of issues with when things happen that can be tricky. It also has the problem that most of the functions are anonymous, and I don't like anonymous functions (function names help your tools help you). It's also awkward to call your prototype's version of a function if you also have a copy of it (e.g., a "supercall" — not an uncommon operation with hierarchies). For that reason, you see a lot of "frameworks" for building hierarchies, usually using class-based terminology. Here's a list of some of them:
The Class feature of Prootype, a general-purpose JavaScript library
Dean Edwards' base2
John Resig's Simple JavaScript Inheritance (Resig being the person who created jQuery)
Er, um, mine — which as far as I know is being used by about three people. I did it because I had issues with decisions each of the above made. I will be updating it to not use class terminology (and actually releasing it as a tiny library, rather than just a blog post), because none of these adds classes to JavaScript, and acting as though they do misses the point of JavaScript prototypical model.
Of those four, I'd recommend Resig's or mine. Resig's uses function decompilation (calling toString on function instances, which has never been standardized and doesn't work on some platforms), but it works even if function decompilation doesn't work, it's just slightly less efficient in that case.
Before jumping on any of those, though, I encourage you to look at the true prototypical approach advocated by Douglas Crockford (of JSON fame, also a big wig at YUI). Crockford had a great deal of input on the latest version of ECMAScript, and some of his ideas (most notably Object.create) are now part of the latest standard and are finding their way into browsers. Using Object.create, you can directly assign a prototype to an object, without having a constructor function.
I prefer constructor functions (with my syntactic help) for places where I need inheritance, but Crockford's approach is valid, useful, and gaining popularity. It's something you should know about and understand, and then choose when or whether to use.

getElementById Another Question

As an extension question that Felix Kling answered so brilliantly I now need to do a two part check on the data table deployed.
Can anyone tell me how to add to the code below to allow me not only to copy the values of the pcode fields into an array but to check if there is a check in the checkbox with a corresponding row number i.e. route2 is check then add to the array but if route3 is not checked then exclude it.
function GetRoute()
{
var from = document.getElementById('inpAddr').value;
var locations = [from];
for(var i = 2; i <= 400; i++) {
var element = document.getElementById('pcode' + i);
if(element === null) { break; }
locations.push(element.innerHTML);
}
var options = new VERouteOptions();
options.DrawRoute = true;
options.RouteColor = new VEColor(63,160,222,1);
options.RouteWeight = 3;
options.RouteCallback = onGotRoute;
options.SetBestMapView = true;
options.DistanceUnit = VERouteDistanceUnit.Mile;
options.ShowDisambiguation = true;
map.GetDirections(locations,options);
}
Thanks in advance!
Justin

for( var i = 2 ; (element = document.getElementById('pcode' + i)) && i <= 400; i++ )
{
if( document.getElementById('route' + i).checked )
{
locations.push( element.innerHTML );
}
}

function GetRoute() {
var from = document.getElementById('inpAddr').value;
var locations = [from];
// My Modification Starts Here....
var maxLoopValue = 400;
var pcode, currentRoute, nextRoute;
for(var i = 2; i <= maxLoopValue; i++) {
pcode = document.getElementById('pcode' + i);
currentRoute = document.getElementById('route' + i);
// Make sure the currentRoute is 'checked'
if (currentRoute.checked) {
// Make sure there is a 'next' route before trying to check it
if (i < maxLoopValue) {
nextRoute = document.getElementById('route' + (i+1));
// Make sure the 'next' route is 'checked'
if (nextRoute.checked) {
locations.push(element.innerHTML);
}
} else {
// This is the last route, since we know it's checked, include it
locations.push(element.innerHTML);
}
}
}
// My Modification Ends Here....
var options = new VERouteOptions();
options.DrawRoute = true;
options.RouteColor = new VEColor(63,160,222,1);
options.RouteWeight = 3;
options.RouteCallback = onGotRoute;
options.SetBestMapView = true;
options.DistanceUnit = VERouteDistanceUnit.Mile;
options.ShowDisambiguation = true;
map.GetDirections(locations,options);
}

JavaScript "null or not an object" error

I'm running the JavaScript below to place horizontal scrolling text on the banner of my website. It works in one server but not another. I get the following error:
Error: 'this.mqo' is null or not an object
JavaScript:
function start() {
new mq('m1');
/* new mq('m2');
*/
mqRotate(mqr); // must come last
}
window.onload = start;
// Continuous Text Marquee
// permission to use this Javascript on your web page is granted
// provided that all of the code below in this script (including these
// comments) is used without any alteration
function objWidth(obj) {
if (obj.offsetWidth) return obj.offsetWidth;
if (obj.clip) return obj.clip.width;
return 0;
}
var mqr = [];
function mq(id) {
this.mqo = document.getElementById(id);
var wid = objWidth(this.mqo.getElementsByTagName('span')[0]) + 5;
var fulwid = objWidth(this.mqo);
var txt = this.mqo.getElementsByTagName('span')[0].innerHTML;
this.mqo.innerHTML = '';
var heit = this.mqo.style.height;
this.mqo.onmouseout = function () {
mqRotate(mqr);
};
this.mqo.onmouseover = function () {
clearTimeout(mqr[0].TO);
};
this.mqo.ary = [];
var maxw = Math.ceil(fulwid / wid) + 1;
for (var i = 0; i < maxw; i++) {
this.mqo.ary[i] = document.createElement('div');
this.mqo.ary[i].innerHTML = txt;
this.mqo.ary[i].style.position = 'absolute';
this.mqo.ary[i].style.left = (wid * i) + 'px';
this.mqo.ary[i].style.width = wid + 'px';
this.mqo.ary[i].style.height = heit;
this.mqo.appendChild(this.mqo.ary[i]);
}
mqr.push(this.mqo);
}
function mqRotate(mqr) {
if (!mqr) return;
for (var j = mqr.length - 1; j > -1; j--) {
maxa = mqr[j].ary.length;
for (var i = 0; i < maxa; i++) {
var x = mqr[j].ary[i].style;
x.left = (parseInt(x.left, 10) - 1) + 'px';
}
var y = mqr[j].ary[0].style;
if (parseInt(y.left, 10) + parseInt(y.width, 10) < 0) {
var z = mqr[j].ary.shift();
z.style.left = (parseInt(z.style.left) + parseInt(z.style.width) * maxa) + 'px';
mqr[j].ary.push(z);
}
}
mqr[0].TO = setTimeout('mqRotate(mqr)', 10);
}

The reason is most likely that there is no element with the id "m1". Place this line first in the start function to diagnose this:
alert(document.getElementById('m1'));
If it shows "[Object]" (or similar), the element exists and it's some other problem, but if it shows "undefined" it means that there is no such element in the page.