Please see code below. I will have a bunch of elements, that I want to run whatever "formula" refers to, for that element. In the code, where it says, "this works", it works as expected. However I need to fire off these formulas, without naming "firstElement" explicitly. Even though the nested for loop is a little clunky, I think it should work, but it causes the error listed below. How can I fire off the formulas, without naming the elements explicitly? Thanks!
var test:Object = {
element:
[
{ "firstElement":
{
formula:myFunction
}
}
]
}// end test object
public function RunThisFunctionFirst() {
test.element[0].firstElement.formula();//this works
for (var index in test.element){
for (var object in test.element[index]){
trace ("object " + object);// traces "firstElement", as expected
object.formula()// this causes error: Error #1006: value is not a function.
}
}
}
function myFunction (){
trace ("my function called");
}
Using a for each loop you can simplify your loop, and as previously said don't forget to typed your variable :
for each (var elm:Object in test.element) {
for each (var obj:Object in elm) {
var formula:Function = obj.formula as Function
if (formula!=null) formula()
}
}
Your variable object, in (var object ... ) is not a typed variable. The compiler will default this to an Object class, which of course is not a Function class. Try casting object as a Function. I'm guess that you have extended myFunction from Function class.
either by:
for (var object:Function in test.element[index])
or
for (var object:myFunction ... ) // if myFunction is extended from Function
Regarding the outer loop, element is an array, not an object, so you want to use for(;;) not for in.
Regarding the inner loop, object is the string "firstElement" not an object.
for (var i:int=0; i < test.element.length; i++)
{
for (var key:* in test.element[i])
{
trace("key " + key);
var object:* = test.element[i][key];
trace("object " + object);
if(typeof object === "object" && object.hasOwnProperty("formula"))
object.formula();
}
}
Related
I'm having real trouble trying to access the symbol dynamically, I have 9 buttons that all call this method, and they pass in their location (tl, t, tr, etc.) I've tried this method before on another program and it works without a problem, but in this program it fails.
I am attempting to access a symbol call s_tl (example location), but all I'm getting is undefined (see results).
function turn(btn : String):Function {
return function(e:MouseEvent) {
var players_turn : int;
var chosen : String = "s_" + btn;
trace(this);
trace(this[chosen]);
trace(chosen);
trace(this[chosen]);
// if crosses turn 0 else 1
if (s_c.currentFrame == 1) {
players_turn = 0;
} else {
players_turn = 1;
}
// check who's turn it is if it's been pressed before
if (players_turn == 0 && this[chosen].visible == false) {
this[chosen].gotoAndStop(1);
this[chosen].visible = true;
} else {
this[chosen].gotoAndStop(2);
this[chosen].visible = true;
}
};
}
Results:
[object global]
undefined
s_br
undefined
TypeError: Error #1010: A term is undefined and has no properties.
at MethodInfo-6()
Your problem is the bad code style. You define unnamed unbind function inside function turn() and that's where the root of your problem is. Unbind function exist, as your trace shows, in global addressing context and, unlike function turn(), is not bind to any specific display object. Your buttons probably exist on the same addressing context with turn(). Argument btn is available inside unnamed function because ECMA standard instructs so (if function A creates function B then local variables, including arguments, of A are available as local variables in B), but it is a very very very bad practice that makes code messy and induce headaches.
Please explain what you tried to achieve with that code so we could untangle it and rewrite in not-so-twisted way.
Okey, I basically figured you're doing Tic Tac Toe. Now, guideline. A cell must contain 3 frames: 1st frame for the button graphics, 2nd and 3rd for X and O. Name them your way: s_1, s_2, etc.
for (var i:int = 1; i < 10; i++)
{
var aCell:MovieClip = getChildByName("s_" + i) as MovieClip;
aCell.addEventListener(MouseEvent.CLICK, onTic);
}
function onTic(e:MouseEvent):void
{
var playersTurn:int = s_c.currentFrame;
var aCell:MovieClip = e.currentTarget as MovieClip;
trace(aCell.name);
// Now, the magic.
aCell.gotoAndStop(playersTurn + 1);
aCell.removeEventListener(MouseEvent.CLICK, onTic);
}
I am having trouble passing a kata. I believe I am on the right track, but do not fully understand how to retrieve the desired results.
The Instructions
Write a method that takes in a function and the arguments to the function and returns another function which when invoked, returns the result of the original function invoked with the supplied arguments.
Example Given
Given a function add
function add (a, b) {
return a + b;
}
One could make it lazy as:
var lazy_value = make_lazy(add, 2, 3);
The expression does not get evaluated at the moment, but only when you invoke lazy_value as:
lazy_value() => 5
Here is my half a day endeavor conclusion
var make_lazy = function () {
var innerFunction = null;
var array = [];
for (var i = 0; i < arguments.length; i++) {
if (typeof arguments[i] == 'function') {
innerFunction = arguments[i];
} else {
array.push(arguments[i]);
}
}
innerFunction.apply(innerFunction, array);
innerFunction();
};
I'm using arguments and apply() and think I am close? However I am getting TypeError: lazy_sum is not a function at Object.exports.runInThisContext within test results. Any help, especially understanding what is going on, is appreciated. Thanks
...
return function() {
return innerFunction.apply(this, array);
};
};
Thanks again all. Problem solved.
I'm attempting to gradually refactor existing code. I have a set of functions that are defined, and only differ by one of the internal arguments:
function loadGame1():void
{
loadGame("save1");
}
function loadGame2():void
{
loadGame("save2");
}
function loadGame3():void
{
loadGame("save3");
}
//... snip many, many lines
// Note- I cannot pass function arguments at this time!
picker(loadGame1, loadGame2, loadGame3 ...);
I'm trying to refactor at least part of this (I can't completely replace the whole thing yet, too many interdependencies).
Basically, I want to be able to generate a big set of functions with the difference between the functions being a internal parameter:
var fNames:Array = new Array("save1", "save2", "save3");
var funcs:Array = new Array();
for (var i = 0; i < fNames.length; i += 1)
{
trace("Creating function with indice = ", i);
funcs.push(
function() : void
{
saveGame(fNames[i]);
}
)
}
picker(funcs[0], funcs[1], funcs[2] ...);
However, as I understand it, closure is causing the state of i to be maintained beyond the scope of the for loop, and any attempt to call any of the generated functions is failing with an out-of-bounds error, which is what you would expect given that i will reach fNames.size + 1 before i < fNames.size evaluates to false.
So, basically, given that I need to generate functions that are passed as arguments to a pre-existing function that I cannot change currently. How can I dynamically generate these functions?
Try to use IIFE:
for (var i = 0; i < fNames.length; i += 1)
{
(function(i){
trace("Creating function with indice = ", i);
funcs.push(
function() : void
{
saveGame(fNames[i]);
}
)
})(i);
}
I'm no code genius, but a fan of action script.
Can you help me on this:
I have a function that depending on the object selected, will call event listeners to a set of 'sub-items' that are already on stage (I want to reuse this subitems with changed parameters upon click, instead of creating several instances and several code).
So for each selected 'case' I have to pass diferent variables to those 'sub-items', like this:
function fooMenu(event:MouseEvent):void {
switch (event.currentTarget.name)
{
case "btUa1" :
trace(event.currentTarget.name);
// a bunch of code goes here
//(just cleaned to easy the view)
/*
HELP HERE <--
here is a way to pass the variables to those subitems
*/
break;
}
}
function fooSub(event:MouseEvent):void
{
trace(event.target.data);
trace(event.currentTarget.name);
// HELP PLEASE <-> How can I access the variables that I need here ?
}
btUa1.addEventListener(MouseEvent.CLICK, fooMenu);
btUa2.addEventListener(MouseEvent.CLICK, fooMenu);
btTextos.addEventListener(MouseEvent.CLICK, fooSub);
btLegislacao.addEventListener(MouseEvent.CLICK, fooSub);
Anyone to help me please?
Thank very much in advance. :)
(I'm not sure I got your question right, and I haven't developed in AS3 for a while.)
If you want to simply create function with parameters which will be called upon a click (or other event) you can simply use this:
btUa1.addEventListener(MouseEvent.CLICK, function() {
fooMenu(parameters);
});
btUa2.addEventListener(MouseEvent.CLICK, function() {
fooMenu(other_parameters)
}):
public function fooMenu(...rest):void {
for(var i:uint = 0; i < rest.length; i++)
{
// creating elements
}
}
If you want to call event listeners assigned to something else you can use DispatchEvent
btnTextos.dispatchEvent(new MouseEvent(MouseEvent.CLICK))
Remember, you can't use btTextos.addEventListener(MouseEvent.CLICK, carregaConteudo("jocasta")); because the 2nd parameter you pass while adding Eventlistener will be considered as function itself - there are two proper ways to use addEventListener:
1:
function doSomething(event:MouseEvent):void
{
// function code
}
element.addEventListener(MouseEvent.CLICK, doSomething); //notice no brackets
2:
element.addEventListener(MouseEvent.CLICK, function() { // function code });
So:
function fooSub(event:MouseEvent, bla:String):void
{
trace(event.currentTarget.name+" - "+bla);
// bla would be a clip name.
}
codebtTextos.addEventListener(MouseEvent.CLICK, function(e:MouseEvent) { fooSub(e, "jocasta") } );
Or try something like this if you want content to be dynamically generated:
btUa1.addEventListener(MouseEvent.CLICK, function() {
createMenu(1);
});
btUa2.addEventListener(MouseEvent.CLICK, function() {
createMenu(2);
});
function createMenu(id):void
{
// Switching submenu elements
switch (id)
{
case 1:
createSubmenu([myFunc1, myFunc2, myFunc3]); // dynamically creating submenus in case you need more of them than u already have
break;
case 2:
createSubmenu([myFunc4, myFunc5, myFunc6, myFunc7]);
break;
default:
[ and so on ..]
}
}
function createSubmenu(...rest):void {
for (var i:uint = 0; i < rest.length; i++)
{
var mc:SubItem = new SubItem(); // Subitem should be an MovieClip in library exported for ActionScript
mc.addEventListener(MouseEvent.CLICK, rest[i] as function)
mc.x = i * 100;
mc.y = 0;
this.addChild(mc);
}
}
Your question is rather vague; what "variables" do you want to "pass"? And what do you mean by "passing the variable to a sub item"? Usually "passing" means invoking a function.
If you can be more specific on what exactly your trying to do that would be helpful. In the meantime, here are three things that may get at what you want:
You can get any member of any object using bracket notation.
var mc:MovieClip = someMovieClip;
var xVal:Number = mc.x; // The obvious way
xVal = mc["x"]; // This works too
var propName:String = "x";
xVal = mc[propName] ; // So does this.
You can refer to functions using variables
function echo(message:String):void {
trace(message);
}
echo("Hello"); // The normal way
var f:Function = echo;
f("Hello"); // This also works
You can call a function with all the arguments in an array using function.apply
// Extending the above example...
var fArgs:Array = ["Hello"];
f.apply(fArgs); // This does the same thing
Between these three things (and the rest parameter noted by another poster) you can write some very flexible code. Dynamic code comes at a performance cost for sure, but as long as the frequency of calls is a few hundred times per second or less you'll never notice the difference.
The following code will add only the last Widget in the loop to all the listener functions. All the functions will call toggleShow() on the last object.
Why does this happen, and is there a way to get each Widget object to be referenced in the corresponding function?
for each (var w:Widget in workspace.getWidgetList()) {
var widgetShow:NativeMenuItem = menu.addItem(new NativeMenuItem("Show " + w.title));
widgetShow.addEventListener(Event.SELECT, function():void {
w.toggleShow();
});
}
Make it a function, this happens because the loop runs to the end and w becomes the last element in that list so when the anonymous function is called it always uses the last element :
for each (var w:Widget in workspace.getWidgetList()) {
addMenuItem(w);
}
function addMenuItem(w:Widget):void
{
var widgetShow:NativeMenuItem = menu.addItem(new NativeMenuItem("Show " + w.title));
widgetShow.addEventListener(Event.SELECT, function():void {
w.toggleShow();
});
}