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Garmin and Monkey C "Cannot find symbol ':setText'..."

I want to try a garmin WachFace and came across very quickly folgnden error, but unfortunately I do not know why it occurs, maybe someone can help you?
Cannot find symbol ':setText' on type 'PolyType<Null or $.Toybox.WatchUi.Drawable>'
I use the following code:
function onUpdate(dc as Dc) as Void {
setClockDisplay();
setDateDisplay();
setBatteryDisplay();
setStepCountDisplay();
setStepGoalDisplay();
setNotificationCountDisplay();
setHeartrateDisplay();
// Call the parent onUpdate function to redraw the layout
View.onUpdate(dc);
}
private function setClockDisplay() {
var clockTime = System.getClockTime();
var timeString = Lang.format("$1$:$2$", [clockTime.hour, clockTime.min.format("%02d")]);
var view = View.findDrawableById("TimeLabel");
view.setText(timeString);
}
}
The error is thrown for all .setText(). In this case 9 times
I have tried everything I could think of.

the following solves the problem:
change
var view = View.findDrawableById("TimeLabel");
into
var view = View.findDrawableById("TimeLabel") as Text;
done!

Javascript: Basic for loop is not working

Is there any reason why the following would not work:
for (i=0;i < someArray.length;i++) {
if (someArray[i].indexOf("something") !== -1) {
//do something here
}
}
The most basic "for" loop possible. But it doesn't work. On the first line (declaration of the loop, not inside the loop), I get "Uncaught reference error; i is not defined."
I have this page open in one Chrome tab, and another earlier version of the page open in another tab. In the other tab, this loop works just fine; in the first tab, this code throws an error.
EDIT - July 2 2015
The response about strict mode was helpful. After reading up a bit and going through the code I've got a handle on what's going on.
The confusing bit was that both versions of the code look like this, with some minor differences (requirejs module):
define(
'viewModels/someViewModel',
['dependency1', 'dependency2', 'dependency3'],
function(dep1, dep2, dep3) {
"use strict";
function SomeViewModel(arg1, arg2) {
var self = this;
self.initialize();
self.removeRefinement = function(refinementString) {
var refinementArray = refinementString.split("&");
for (i=0;i < navigationArray.length;i++) { //<-- error
}
}
}
}
);
One version throws the reference error. One doesn't.
This is a large web application with many other pages and Javascript files. The only thing I could think of was that in one version of the code, maybe i had been inadvertently globally defined somewhere else in the app, where strict mode wasn't enabled. After running to the breakpoint and checking "window" I see that's exactly what's happening.
Thanks =D

If you are in strict mode, you'll get the error Uncaught reference error; i is not defined. If you're not in strict mode, you won't get the error.
This will throw the error
'use strict'
var someArray = ['aaa', 'bbb', 'ccc'];
for (i=0;i < someArray.length;i++) {
console.log(i)
if (someArray[i].indexOf("something") !== -1) {
//do something here
}
}
This won't
var someArray = ['aaa', 'bbb', 'ccc'];
for (i=0;i < someArray.length;i++) {
console.log(i)
if (someArray[i].indexOf("something") !== -1) {
//do something here
}
}

when you declare a variable it must be declared like this var i = 0;
a for loop looks like this:
JavaScript
for(var i = 0; i == 10; i++)
{
}

Basic var misunderstanding

I have created this:
var where = function(){
sym.getSymbol("Man").getPosition()
}
console.log(where);
if (where()<=0){
var playMan = sym.getSymbol("Man").play();
} else {
var playMan = sym.getSymbol("Man").playReverse();
}
This is for Edge Animate hence all the syms. I am trying to access the timeline of symbol Man, then if it is at 0 play it. But it isnt working and the reason, I think, is that I have an incomplete understanding of how a var works. In my mind I am giving the variable 'where' the value of the timeline position of symbol 'Man'. In reality the console is just telling me I have a function there, not the value of the answer. I have run into this before and feel if I can crack it I will be a much better human being.
So if anyone can explain in baby-language what I am misunderstanding I would be grateful.
Thanks
S

var where = function () { ... };
and
function where() { ... }
are essentially synonymous here. So, where is a function. You are calling that function here:
if (where()<=0)
However, the function does not return anything. You need to return the value from it, not just call sym.getSymbol("Man").getPosition() inside it.
That, or don't make it a function:
var where = sym.getSymbol("Man").getPosition();
if (where <= 0) ...
The value will only be checked and assigned once in this case, instead of updated every time you call where().

Try
var where = function()
{
return sym.getSymbol("Man").getPosition();
};
Your code wasn't returning anything.

var where = function() {
return sym.getSymbol("Man").getPosition()
}
console.log(where);
if(where()<=0) {
var playMan = sym.getSymbol("Man").play();
} else {
var playMan = sym.getSymbol("Man").playReverse();
}

How to trace Javascript events (Stack Trace )?

In any programming language, I can trace any function and know which function is called by other. But in Javascript , I don't know how, since the code is not written by me and Firebug does not give this feature - as far as I know.
An example :
I want to display the function names of each function that is called when clicking on XYZ Element, and display them in order.

Found this: A javascript stacktrace in any browser, James says they have a github account now
function printStackTrace() {
var callstack = [];
var isCallstackPopulated = false;
try {
i.dont.exist+=0; //doesn't exist- that's the point
} catch(e) {
if (e.stack) { //Firefox
var lines = e.stack.split('\n');
for (var i=0, len=lines.length; i<len; i++) {
if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
callstack.push(lines[i]);
}
}
//Remove call to printStackTrace()
callstack.shift();
isCallstackPopulated = true;
}
else if (window.opera && e.message) { //Opera
var lines = e.message.split('\n');
for (var i=0, len=lines.length; i<len; i++) {
if (lines[i].match(/^\s*[A-Za-z0-9\-_\$]+\(/)) {
var entry = lines[i];
//Append next line also since it has the file info
if (lines[i+1]) {
entry += " at " + lines[i+1];
i++;
}
callstack.push(entry);
}
}
//Remove call to printStackTrace()
callstack.shift();
isCallstackPopulated = true;
}
}
if (!isCallstackPopulated) { //IE and Safari
var currentFunction = arguments.callee.caller;
while (currentFunction) {
var fn = currentFunction.toString();
var fname = fn.substring(fn.indexOf("function") + 8, fn.indexOf('')) || 'anonymous';
callstack.push(fname);
currentFunction = currentFunction.caller;
}
}
output(callstack);
}
function output(arr) {
// Output however you want
alert(arr.join('\n\n'));
}

You can see the stack trace of any error with the stack() function call (on Firefox). Creating a simple function to print a stack trace could look like this:
function getStackTrace() {
try {
unusedVariable++; // This creates an error we can trace
}
catch (e) {
return e.stack;
}
}
Other browsers have different ways of printing the stack trace, but this should get you what you need for Firefox.
Hope this helps.

DynaTrace AJAX has some of the features like that. Not exactly what you are looking for but gives you the events and functions bound on an element and helps your troubleshooting. Had a free download, check it.

If you simply want to debug your code, your best option is to get a debugger plug-in for your browser. The Firebug plug-in does provide stack traces. (see here)
If you want to do it from within your code, there is no standard language feature of JavaScript that allows you to do this. Different browsers may implement non-standard extensions, but you shouldn't rely on them.

As "Casablanca" mentions... please note from the site of the aforementioned js-stack-trace (
http://www.eriwen.com/javascript/js-stack-trace/ ) that in FireFox and Chrome:
Obvious easy way: Firebug, Chrome Dev Tools, Dragonfly etc.
You can easily get a stack trace at any time by calling
console.trace() in your Javascript or in the Firebug console.

Since it sounds like you want to inspect the stack and take pieces of the information (the function names), sounds like you need
stackinfo
which was built exactly for that purpose.

Problem with Javascript object and accessing property which exists

I have something like this:
var test = {};
function blah() {
test[2] = 'filled';
}
blah(); // ! Hopefully confusion is now averted..
console.log(test);
//result test -> 2:"filled"
console.log(test[2]);
//result undefined
I don't understand why I'm getting 'undefined' in the second instance when according to the first instance, the property of that object clearly exists!
Does anyone have any ideas?
Thanks
OK, it seems that folk are getting confused as to what context the code exists in, for clarity sake I have now added the call to the blah(). but please refer to the comment under Jeff B's response!
Here is an example of relevant code so to say:
mydb = ..... //gets created here with relevant credentials
var test = {};
mydb.transaction(
function(transaction) {
transaction.executeSql("select * from mytable;", [], function(transaction,result) {
var r = result.rows.item(0);
test[2] = r.title;
}, errorHandler);
});
console.log(test);
//result test -> 2:"the title"
console.log(test[2]);
//result undefined
#Dancrumb
Your mention of the single-threadedness of Javascript gave me an idea, and I tried this:
window.setTimeout(function(){ alert(test[2]); },2000);
and it worked! I got the expected value to alert. Can you suggest how I can get around this without using a 'hack' like that above?

Because you aren't calling blah()?
Also, you want:
var test = [];
or:
var test = new Array();

EDIT
I ran the following code:
mydb = openDatabase('note','','Example',1024);
var test = {};
mydb.transaction(
function(transaction) {
transaction.executeSql("select * from mytable;", [], function(transaction,result) {
var r = result.rows.item(0);
test[2] = r.title;
}, errorHandler);
});
console.log(test);
console.log(test[2]);
in Safari 4.0.5
I got the following:
Object
No Properties
undefined
This is what I would expect to see. The object test does not have any properties assigned to it until the callback from mydb.transaction occurs and, since Javascript is single threaded, this cannot happen before the calls to console.log.
Since you're getting a different outcome, can you outline what browser and what version you are using?

This is pretty clearly an asynchronous issue. The simplest way of getting code to run after you set test[2], is to either put the code right there, or use another callback, and call it after you set test[2].