Tag Archives: javascript

Dynamic Getter

By Zevan | July 18, 2018

Getters in ES6 are usually defined within a class like this:

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  class RandomPoint {
    get x() {
      return Math.random();
    }
    get y() {
      return Math.random();
    }
  }

In this case we use getters to make a random point:

  let pnt = new RandomPoint();
  console.log(pnt.x, pnt.y);
  // outputs something like 0.09403673512366306 0.2717692041118973

I found myself wanting to be able to dynamically define a getter. This can be done like this:

let rand = function() { return Math.random(); };
Object.defineProperties(someObj, { ['x']: { get: rand });

This is really all just sugar, but still fun stuff…

Posted in Uncategorized, javascript | Also tagged | Leave a comment

HTML5 Canvas Tutorial

By Zevan | July 21, 2012

If you haven’t tried the html5 canvas tag yet, I suggest you give it a try. It falls under the same category as ActionScript’s Graphics and BitmapData classes. It is however much much simpler. One great thing about it is it runs really fast on IOS5. Have a look at some of these demos to see what I mean: http://zreference.com/projects/graphics/

A few days ago I recorded this short video tutorial… it’s very simple, but it will get you started if you’ve never tried canvas before:

Posted in html5, javascript | Also tagged , , , | 2 Comments

Hide Browser Scrollbars

By ascontest | November 9, 2009
CLICK HERE TO COPY
Actionscript:
  1. /*
  2. This snippet is by Mels le Noble
  3. www.melslenoble.nl
  4. It will hide the browser scrollbars.
  5. */
  6.  
  7. // see if we are testing locally
  8. if (stage.loaderInfo.url.split("/")[2])
  9. {
  10.  ExternalInterface.call("function(){document.body.style.overflow='hidden';document.html.style.overflow = 'hidden';}");
  11. }

This snippet by Mels le Noble will hide the browser scrollbars. The bulk of the snippet is the javascript inside the ExternalInterface.call() method. I like the trick that Mels uses to check if the swf is local.... snippet-worthy in itself.

Posted in UI | Also tagged , , , | Leave a comment

JS Sketch Experiment

By Zevan | October 5, 2009
CLICK HERE TO COPY
Actionscript:
  1. [SWF(width=950, height=600)]
  2. with (graphics) beginFill(0xefefef), drawRect(0,0,stage.stageWidth, stage.stageHeight);
  3. var btn:Sprite = Sprite(addChild(new Sprite()));
  4. with (btn.graphics) beginFill(0x666666), drawRect(0,0,100,20);
  5. with(btn)  x=320, y=430, buttonMode = true;
  6. btn.addEventListener(MouseEvent.ROLL_OVER, function():void{
  7.   with(btn.graphics) clear(), beginFill(0x222222), drawRect(0,0,100,20);
  8. });
  9. btn.addEventListener(MouseEvent.ROLL_OUT, function():void{
  10.   with(btn.graphics) clear(), beginFill(0x666666), drawRect(0,0,100,20);
  11. });
  12. btn.addEventListener(MouseEvent.CLICK, function():void{
  13.     var res:*= ExternalInterface.call("function(){ plot=[]; colors=[]; " + txt.text + " return {plot:plot, colors:colors};}");
  14.     render((res == null) ? {plot:[], colors:[]} : res);
  15. });
  16.  
  17. var v:Shape = Shape(addChild(new Shape()));
  18. v.x = 700;
  19. v.y = 220;
  20. function render(obj:Object):void{
  21.     var plot:Array = obj.plot;
  22.     var colors:Array = obj.colors;
  23.     var leng:int = plot.length;
  24.     v.graphics.clear();
  25.     var inc:int = 0;
  26.     v.graphics.moveTo(plot[0], plot[1]);
  27.     for (var i:int = 2; i<leng; i+=2){
  28.         v.graphics.lineStyle(0,colors[inc++]);
  29.         v.graphics.lineTo(plot[i], plot[i + 1]);
  30.     }
  31. }
  32.  
  33.  
  34. var submit:TextField = TextField(btn.addChild(new TextField()));
  35. submit.defaultTextFormat = new TextFormat("_sans", 12);
  36. with(submit) textColor=0xFFFFFF, width=100, autoSize="center";
  37. with(submit) mouseEnabled = false,  text="submit";
  38.  
  39. var txt:TextField = TextField(addChild(new TextField()));
  40. with(txt) x = y = 20, type = "input", multiline=true;
  41. with(txt) width = 400, height = 400, border = true, background = 0xFFFFFF;
  42. txt.defaultTextFormat = new TextFormat("Monaco", 12);
  43. txt.text = "enter text";
  44. txt.addEventListener(MouseEvent.MOUSE_DOWN, onDown);
  45. function onDown(evt:MouseEvent):void{
  46.     txt.text = "";
  47.     txt.removeEventListener(MouseEvent.MOUSE_DOWN, onDown);
  48. }

This snippet is a mini code editor that allows the user to write javascript into a textfield - the javascript is then run using external interface. Optionally the javascript code can populate two arrays (plot and colors). If these arrays are populated flash, will render the data in each array using the Graphics class.

Have a look at the demo:

If you do something nice with this... post your javascript snippet as a comment and I'll add it to the JS Sketch page...

Posted in Graphics, Math, dynamic, external data, functions | Also tagged , , | Leave a comment