Animate an image

Question

I have a read a few ways to animate an image in AS3 and not sure what is the most efficient way.
I  want to load 4 images(in 4 files) in a class. Each image is a different  frame of a walking movement of a character. What I want to do is load  all the images in the constructor and assign the sprite the current  frame to display.
eg sprite=bitmap1  then after some time swap images so
sprite=bitmap2  then after some time swap images so etc
sprite=bitmap3....
Is this the logic you do in AS3?
The code loads 1 image so I can change this to 4 images to load (4 bitmaps and 1 sprite for the current frame?)
private  var sp:Sprite=new Sprite();
          public function ClassImg2(myimg:String,xx:int,yy:int)     {
          img1=myimg;
               myx=xx;
               myy=yy;
          var loader:Loader = new Loader;
          loader.contentLoaderInfo.addEventListener(Event.COMPLETE, imageLoaded);
          loader.load(new URLRequest(img1));
          private function imageLoaded(event:Event):void
           var image:Bitmap = new Bitmap(event.target.content.bitmapData);
             sp.addChild(image);
             sp.x = myx;
             sp.y = myy;
             addChild(sp);

Answer 1

HI have spent ages on this and snippets of code isnt clarifying this for me.
I want to load images into BItmapData and display one of those to the screen Bitmap. To animate I want to swap images every so often
I need to know
1)I dont know how to load an image into a bitmapData object
2) I need to assign the bitmapData to a bitmpa so I can display it
3) I will need to perform keyevents/mouse events on the image display on screen so the bitmap  must be converted to a sprite somehow.
IT would help me the most if someone was to look at my code and I will try to find some AS3 animation tutorials complete examples (NOT EASY!)
private   var img1:Bitmap;
          private   var bmp:BitmapData;
            private var MyImages:Array = [];
            var urls:Array = ["scave4.png", "scave5.png", "scave6.png", "scave7.png"];
          public function ClassImg3()     {
          imgStr="scave4.png";
               for each (var el:String in urls) {
                    var loader:Loader = new Loader;
                    loader.contentLoaderInfo.addEventListener(Event.COMPLETE, imageLoaded);
                    loader.load(new URLRequest(el));
          private function imageLoaded(event:Event):void
          // var image:Bitmap = new Bitmap(event.target.content.bitmapData);
          // img1= new Bitmap(event.target.content.bitmapData);
            var bmd:BitmapData = event.target.loader.content.bitmapData;
          // bmp=new BitmapData(event.target.content.bitmapData);
            MyImages.push(bmd);
          img1.bitmapData = bmd;
          addChild(img1);
          img1.x =30;
          img1.y=100;
            // sp.addChild(image);
             //sp.x = myx;
            // sp.y = myy;
             //addChild(sp);
             dispatchEvent(new Event("image_loaded"));
          public function moveChar()
               img1.x+=1
               if (img1.x>400)
                    img1.x=10;