I want to create several beats in a measure (using SVGs), and place them beside each other. I am a bit confused how to keep track of the iterator in underscore.js to use in the function itself.
Here is what I have :
_.each(beats, function(beat) {
// create a beatview
var measurePassingToBeatViewParamaters = {
beatXLocation: beatXLocation
// i want this to be something like beatXLocation: beatXLocation * beatCountIterator
};
new beatView(measurePassingToBeatViewParamaters); //backbone View
// then somewhere increase the beatCountIterator ++;
}, this); //this is a measure
Here you go.
"Each invocation of iterator is called with three arguments: (element, index, list)."
Edit:
_.each(beats, function(beat, index)
Or:
_.each(beats, function(beat) {
index = arguments[1];
Sorry if it's not what you meant.
Related
I have a computed array which is full of tags and updates depending on what selection i make in the select box. I would like to take this array and pass it to a method and then run a method to update what “results” have an active class. Although I get an array saying I can’t run forEach on this element.
Been through a few topics and understand computed properties dont work like that but surely there is a way around this.
https://jsfiddle.net/39jb3fzw/6/
Short Snippet
methods: {
updateOutput() {
var tags = this.tagArray;
tags.forEach(function(tag) {
console.log(tag);
})
}
},
computed: {
concatenated: function () {
var ret = this.selected.concat(this.selected2, this.selected3);
this.tagArray = ret;
//this.updateOutput();
return ret;
}
}
Full Output
https://jsfiddle.net/39jb3fzw/6/
Thanks again :slight_smile:
It looks like the issue is the line:
var ret = this.selected.concat(this.selected2, this.selected3);
That line of code is returning an empty string rather than an array. This is because this.selectedX is a string rather than an Array. This explains why tag.forEach is undefined. forEach doesn't exist on the String prototype.
You can create this an array instead be doing
var ret = [ this.selected, this.selected2, this.selected3 ]
From there you can set this.tagArray to ret
Hope this helps
From what my friend has told me, this should be working but it is not.
var P2hb:Array = new Array(P2char1, P2char2, P2char3);
var P2life:Number = 0;
addEventListener(Event.ENTER_FRAME, framecheck)
function framecheck(event:Event):void
{
if (P2hb.hitTestObject(P1attack)) { P2life-=2; }
}
This is a generic code but it is the same as what I have. Basically,
all elements in the P2hb are movieclips on the stage.
I want to say that, if P1attack hits any of the objects in the array, then P2life will drop by 2, without having to type hitTestObject() for each individual object.
I can't seem to get it to work. Can anyone tell me what I am doing wrong?
Thank you in advance.
Simply, loop through each individual "movieClip" in the array (using a for loop, for example) and check for the collision against your other object:
function framecheck(event:Event):void
{
for each (var enemy in P2hb) {
if (enemy.hitTestObject(P1attack)) {
P2life-=2;
trace("hit occurred! P2life: "+P2life);
}
}
}
i use the following function to retrieve a random person from an array:
func getRandomPerson() -> String{
if(personArray.isEmpty){
return ""
} else {
var tempArray: [String] = []
for person in personArray{
tempArray += [person.getName()]
}
var unsignedArrayCount = UInt32(tempArray.count)
var unsignedRandomNumber = arc4random_uniform(unsignedArrayCount)
var randomNumber = Int(unsignedRandomNumber)
if tempArray.isEmpty {
return ""
} else {
return tempArray[randomNumber]
}
}
}
I would like to use this function inside an array of strings, Like this:
var theDares: [String] = ["Dare1 \(getRandomPerson())", "Dare2", "Dare3", "Dare4", "Dare5"]
But when i use the functions, it only runs the function once. Can you make the function run everytime you use the "Dare1" in this instance.
Thanks in advance
I think you are asking if you can set up your array so every time you fetch the object at index 0, it re-builds the value there.
The short answer is no. Your code is creating an array of strings, and the item at index 0 is built ONCE using a function call.
However, it is possible to make a custom class implement the subscript operator. You could create a custom object that looks like an array and allows you to index into it using an Int index. In response to the index operator you could run custom code that built and returned a random string.
Since it sounds like you're a beginning programmer creating a custom class the implements the subscript operator might be beyond your current abilities however.
Try like this:
let personArray = ["John", "Steve", "Tim"]
var randomPerson: String {
return personArray.isEmpty ? "" : personArray[Int(arc4random_uniform(UInt32(personArray.count)))]
}
println(randomPerson) // "Steve"
i've created an array. Each element is a button object. Is there a possibility to hook mouseclick on every array at the same time? I mean something like this.
var Objects:Array = new Array
Objects[0] = new button(parameters)
Objects[1] = new button(parameters)
Objects[2] = new button(parameters)
Objects[n].addEventListener(MouseEvent.CLICK, Clicked(n));
function Clicked(n,...)
{
THECODE PROCEEEEDS for Objects[n]
}
I know that's not the clearest and most correct writing, but I'm asking if this is possible in similiar way? And how to do it? I know I can hook every mouseclick and then check if the clicked under the mouse is one of the array elements with for loop, but I'm asking about this way.
Yes. You are unable to directly pass an index into a listener, but you can retrieve that via calling indexOf() inside it.
for each (b in Objects) b.addEventListener(MouseEvent.CLICK, clicked);
// note, you just put function name here!
public function clicked(e:MouseEent):void {
var i:int=Object.indexOf(e.target);
if (i==-1) {
// panic behavior
return;
}
// now you can parse that index into something valuable
}
Here's what I'm currently doing/trying to do to accomplish my goal. But it is not removing the "row" the way I would like it too.
So, I'm making an object, then pushing it into an array. And the adding to the array part works fine and just as I expect.
var nearProfileInfoObj:Object = new Object();
nearProfileInfoObj.type = "userInfo";
nearProfileInfoObj.dowhat = "add";
nearProfileInfoObj.userid = netConnection.nearID;
nearProfileInfoObj.username = username_input_txt.text;
nearProfileInfoObj.sex = sex_input_txt.selectedItem.toString();
nearProfileInfoObj.age = age_input_txt.selectedItem;
nearProfileInfoObj.location = location_input_txt.text;
nearProfileInfoObj.headline = headline_input_txt.text;
theArray.push(nearProfileInfoObj);
So after that later on I need to be able to remove that object from the array, and it's not working the way I'm expecting. I want to take a variable whoLeft and capture their ID and then look in the array for that particular ID in the userid part of the object and if its there DELETE that whole "row".
I know you can do a filter with an array collection but that doesnt actually delete it. I need to delete it because I may be adding the same value again later on.
whoLeft = theiruserIDVariable;
theArray.filter(userLeaving);
public function userLeaving(element:*, index:int, arr:Array):Boolean
{
if (element.userid == whoLeft)
{
return false;
}
else
{
return true;
}
}
But this doesnt seem to be deleting the whole row like it implies. Does anyone know what i'm doing wrong?
Instead of modifying the original array, the new filtered array is returned by the filter method. So you need to assign the returned array to theArray.
Try this
theArray = theArray.filter(userLeaving);
EDIT This turned out to be slower than for loop:
An alternative to the hand coded loop could be something like this:
theArray.every(searchAndDestroy);
public function searchAndDestroy(element:*, index:int, arr:Array):Boolean
{
if (element.userid == whoLeft)
{
arr.splice(index,1);
return false;
}
return true;
}
As far as I know, every() terminates the first time the test function returns false. So the question is: for a big list, which is faster, the for loop or the loop that every() does with the overhead of the test function call.
EDIT #2 But this was faster than a for loop for a test I ran on an array of a million Points:
for each(var element:Object in theArray)
{
if (element.userid==whoLeft)
{
theArray.splice(theArray.indexOf(element),1);
break;
}
}
I think this is what you're looking for:
for(var i:uint = 0, len:uint = theArray.length; i<len; i++)
{
if(thisArray[i].id == whoLeft.id)
{
thisArray.splice(i, 1);
break;
}
}
However, do you really need it in an Array because you could always use a Dictionary which would mean accessing it by id which would be a lot simpler to remove.