I'm getting the following error:
ReferenceError: MyClass is not defined
in meteor 1.2 (actually just updated to 1.2.0.2) with a class defined in lib from a server file.
class MyClass {
// lots of OOP code here .....
}
Do you have to do something special for meteor to pick up the new ES2015 class stuff? Thanks!
You have to declare the class global, like
MyClass = class MyClass { /*...*/ };
Since Meteor wraps all your .js files in IIFOs
As of Meteor 1.3
You should declare your class in imports/.../myClass.js as follows:
export class MyClass {
/* ... */
}
And whereever you want to use it:
import {MyClass} from 'imports/.../myClass';
/* ... */
MyClass.something();
Related
I'm writing a meteor-angular2 application using intellij with typescript.
I created RoomInterface with the following code:
export interface RoomInterface {
id:number;
name:string;
}
then I have the following exported class:
export class Rooms extends MeteorComponent{
rooms:Mongo.Cursor<RoomInterface>;
constructor() {
super();
this.subscribe('rooms',()=>{
this.rooms=RoomsCollection.find();
},true);
}
}
the code runs fine but intellij is complaining with the error type Mongo.Cursor is not generic for rooms:Mongo.Cursor<RoomInterface>;
I'm wondering if I'm missing something.
thanks!
That is because the definition for Mongo.Cursor in this file is not generic:
export interface Cursor extends Readable, NodeJS.EventEmitter {
If it was generic it would be something like:
export interface Cursor<T> extends Readable, NodeJS.EventEmitter {
// Use type T in a meaninful way e.g
results: T[];
Quick Fix
Change rooms:Mongo.Cursor<RoomInterface>; to rooms:Mongo.Cursor;
I have an actionscript class MyClass that extens NavigatorContent. I instantiate the class as a custom MXML NavigatorContnent component for an Accordion component. MyClass has a Button component that I have tried to attach an event listener to. I want the event to bubble so that I can have the handler in the Accordion component.
MyClass
package comp
{
import flash.events.Event;
import flash.events.MouseEvent;
[Event(name="selectEvent", type="flash.events.Event")]
public class MyClass extends NavigatorContent
{
public function MyClass()
{
super();
btnSelect.addEventListener(MouseEvent.CLICK, selectClickDispatcher);
}
public function selectClickDispatcher(event:MouseEvent):void
{
event.currentTarget.dispatchEvent(new Event("selectEvent",true));
}
}
}
From here I have the instantiated component nested in the Accordion. I am pretty sure the problem is in this class definition because when I set a breakpoint at the selectClickHandler, the code does not break. In case I am wrong I will post the rest of the components.
Custom component named MySubComp.mxml
<comp:MyClass
...I have a few more spark components here and nothing else...
/>
Accordion
<mx:Accordion>
<fx:Script> //omitted CDATA tags to save space
protected function selectEventHandler(event:Event):void
{
Alert.show("Value Selected");
}
</fx:Script>
//custom components are in the navs package
<navs:MySubComp selectEvent = "selectEventHandler(event)"/>
</mx:Accordion>
You have added the metadata to the class definition
[Event(name="selectEvent", type="flash.events.Event")]
so all you need to do in mxml is
<comp:MyClass selectEvent="event_handler(event)"
..... />
In AS3, you add an event listener by
myClass.addEventListener("selectEvent", event_handler);
P.S. Your class will have to extend EventDispatcher
Your class either needs to extend a DisplayObject class, or directly inherit from EventDispatcher in order to be able to use events. Forget about implementing IEventDispatcher as there's a special piece of black code somewhere that means that EventDispatcher is the only class that can set the target property of the Event class (I've tried it before).
Consider using other alternatives. Events in Flash tend to be slow and create objects all the time. Callbacks are a good system if you need something simple.
public class A
{
public var onSomething:Function = null;
public function foo():void
{
if( this.onSomething != null )
this.onSomething();
}
}
public class B
{
public function B()
{
var a:A = new A;
a.onSomething = this._somethingCalled; // set the callback
a.init();
}
private function _somethingCalled():void
{
trace( "hello there" );
}
}
You can also take a look at the Signals project: https://github.com/robertpenner/as3-signals/wiki
Signals are vastly superior to normal Flash events, and there's no restriction on the type of object that can use them (i.e. non-DisplayObject objects can still add event listeners and dispatch events). It's also faster and has a smaller memory footprint.
In case someone needs the real Actionscript-3 event dispatching to be used >>> this <<< is very helpful. I don't know if it is really slow but it meets the AS-3 standards.
I want to create a complete (and real) 2-dimensional array.
In order to use a maximum of Adobe code, I want to use ListCollectionView which can manage sort and filters. But to use a second dimension, I need to override getProperty method, like following code.
package
{
import flash.utils.flash_proxy;
import mx.collections.ListCollectionView;
public class SubClass extends ListCollectionView /* extends Proxy */
{
override flash_proxy function getProperty(name : *) : *
{
...
}
override flash_proxy function setProperty(name : *, value : *) : void
{
...
}
}
}
This code doesn't work. Flash Builder 4 said to me:
1004 Namespace was not found or is not a compile-time constant.
If anyone has a solution or a clue...
It's easy :
use namespace flash_proxy;
I'm wondering (based on scoping rules) how I might do the following:
I want to draw to a sprite that exists on the main stage in which I have a class instantiated.
So something like
public function MyClass(reference:String){
this.reference = reference;
}
public function drawToOutsideSprite(){
this.parent.getChildByName(this.reference).addChild(someLoaderName);
}
Would I use super() in this case, or what's the usual methodology?
Thanks,
jml
There are a few ways to do this. I'm assuming your MyClass extends Sprite.
package
{
import flash.display.DisplayObject;
import flash.display.DisplayObjectContainer;
import flash.display.Sprite;
/**
* MyClass
*/
public class MyClass extends Sprite
{
public var referenceA:String;
public var referenceB:Sprite;
public function get referenceA_way2():Sprite
{
return this.parent.getChildByName(referenceA);
}
/**
* MyClass Constructor
*/
public function MyClass(referenceA:String = null, referenceB:Sprite = null)
{
super();
this.referenceA = referenceA;
this.referenceB = referenceB;
}
public function drawToOutsideSpriteA(child:DisplayObject):void
{
// referenceA
this.parent.getChildByName(this.referenceA).addChild(child);
// or
referenceA_way2.addChild(child);
}
public function drawToOutsideSpriteB(child:DisplayObject):void
{
// referenceB
referenceB.addChild(child);
}
public function drawToOutsideSpriteC(referenceC:String, child:DisplayObject):void
{
this.parent.getChildByName(referenceC).addChild(child);
}
// Do this:
// it allows you to abstract out the logic of getting the main sprite
// into some util class, so you could reuse that functionality elsewhere,
// and so your code is cleaner.
public function drawToOutsideSpriteD(child:DisplayObject):void
{
StageUtil.getMainSprite().addChild(child);
}
}
}
package
{
import flash.display.DisplayObject;
import flash.display.DisplayObjectContainer;
import flash.display.Sprite;
/**
* MyClass
*/
public class StageUtil
{
private static var root:Stage;
/**
* Called when app first starts
*/
public static function initialize(stage:Stage):void
{
root = stage;
}
public static function getMainSprite():DisplayObjectContainer
{
return root; // or something more complex,
// like a recursive function to getSpriteByName
}
public static function addToStage(child:DisplayObject):DisplayObject
{
return getMainSprite().addChild(child);
}
}
}
In general I would abstract out the logic for getting the "main" sprite into some util/manager class, because you don't want to hardcode that into your MyClass, as you might need it in other places, and you might want to customize it later on. It sounds like your just asking what's the best way to reference sprites outside of the scope of the MyClass, so I say just put it into the Util, assuming it has good reason for being their (like FlexGlobals.topLevelApplication in Flex, so you can easily access the application).
I don't recommend passing in id's or name's into the constructor and doing it that way, I don't really recommend constructor arguments at all. I would just pass those into a method if you needed to, or have it built into the class itself, or the Util.
To clear up the scoping question a little... You normally don't want to draw to sprites outside the scope of the class you are in, unless they have some special functionality that will be referenced by multiple classes with totally different scopes. This is because things would start not making sense, who's being added to who. But some good examples on when to do thatinclude:
Buttons with ToolTips: Tooltips are added to the root because they appear on top of everything, but a Button could be 20 children deep, so you'd have in the Button subclass, perhaps, addToolTip(child).
PopUps: You might want to add a popup from within MyClass, but it's really being added to the stage. In flex this is like PopUpManager.addPopUp(child), just like the sample StageUtil.getMainSprite().addChild(child). You could even wrap that method so it's like the one in the class above, addToStage.
Transform/Drawing Stage: If you have some global painting stage, or place where you scale/resize things, you might want to be able to add/remove graphics from that from any class.
The super() method isn't useful in this scenario. The only time you really use super() is if you have overridden a method, and want to access the super-classes implementation. Something like this (assuming you're extending Sprite):
override public function addChild(child:DisplayObject):DisplayObject
{
if (child is MyDrawingSprite)
return StageUtil.addToStage(child); // add to main stage
else
return super.addChild(child); // add directly to this class
}
Otherwise, try to stick to just adding children directly to the "MyClass".
Hope that helps.
I have an ugly problem. I have two string variables (className and staticMethod) store the name of a class and it's static method I have to call:
package {
import flash.display.Sprite;
import flash.utils.getDefinitionByName;
import flash.utils.getQualifiedClassName;
public class ClassPlay extends Sprite {
public function ClassPlay() {
new Foo();
var className:String = 'Foo';
var staticMethod:String = 'bar';
var classClass:Class = getDefinitionByName(className) as Class;
try {
classClass[staticMethod]();
} catch (e:Error) {}
}
}
}
This is the subject class:
package {
public class Foo {
public static function bar():void {trace('Foo.bar() was called.');}
}
}
It works just perfectly. The problem when you comment out this (9th) line:
// new Foo();
Without this line it exits with an exception:
ReferenceError: Error #1065: Variable Foo is not defined.
How could I do this without that instantiation? If that is impossible, is there a way to instantiate the class from the string variable? Or if it's still a bad practice, how would you do that? (I have to work with those two unknown string variable.)
Thanks in advance.
The reason is that the compiler will strip out unnecessary classes - if you don't have an explicit reference to the class Foo somewhere, it won't be present in your final application.
You could the reference elsewhere and still force it to be loaded - for example, a static array of references to the classes.
It should work if you just throw in a trace(classClass) - that should give you the reference you need, if I remember this stuff correctly.