how to create a simple animation in pure actionscript (flex sdk only)

I really don't want something sophisticated, in fact I want the simplest animation for learning purpose:

开发者_运维百科

I just want to move a shape on a straight line.

Is it possible to do so in pure actionscript (with flex sdk only) by creating a timeline programmatically or without creating timeline ?

---

If you are using Flash Builder (or Flex Builder) you can accomplish this by creating an ActionScript project. I am a bit unclear when you say you want to use the Flex SDK but in pure ActionScript since Flex is a framework for ActionScript. So if you are talking about mx Effects and Spark Effects please let us know.

The following is for a pure ActionScript 3.0 project.

Ok so you will need a class that extends MovieClip say SimpleFlash. You can extend Sprite instead if you do not need to use a timeline.

import flash.display.MovieClip;

public class SimpleFlash extends MovieClip {
    public function SimpleFlash() {

    }
}

We will need a simple shape to be placed in our SimpleFlash constructor,

var simpleShape:Shape = new Shape();
            simpleShape.graphics.beginFill(0xFF0000);
            simpleShape.graphics.drawRect(0, 0, 100, 100);
            simpleShape.graphics.endFill();
                        simpleShape.x = 0;

And we will have to add an event listener to the shape so that when we enter the first frame, we can execute some animation.

simpleShape.addEventListener(Event.ENTER_FRAME,simpleAnimation);

Do not forget to add it to the display list

addChild(simpleShape);

In our simpleAnimation function (called two lines up) we want to move the shape in a straight line along the x axis.

public function simpleAnimation(event:Event):void {
            event.target.x += 1;
}

The shape after will move 1 unit to the right every time the Event of ENTER_FRAME is fired. There you go a simple animation without the timeline.

What you can learn from this ?

• Change 1 to another number see what happens. Does the shape move faster or slower ?
• Change event.target.x to event.target.y which way does it go ?
• Can you make it go diagonally ? How ?