AS3 - If symbol's coordinates arrive here? - actionscript-3

Question

I'm using Flash Professional CS5.5 and I need to make an app where there is a ball (symbol) that moves using the accelerometer and I want that, when the ball coordinates A reach this coordinates B it goes to frame 2 (gotoAndPlay(2)). I have to find the ball coord first, right? How do I make this?
Here is the code I've now
c_ball.addEventListener(MouseEvent.MOUSE_DOWN, fl_ClickToDrag);
function fl_ClickToDrag(event:MouseEvent):void{
c_ball.startDrag();}
stage.addEventListener(MouseEvent.MOUSE_UP, fl_ReleaseToDrop);
function fl_ReleaseToDrop(event:MouseEvent):void{
c_ball.stopDrag();}
would it work if, after retriving the coordinates?
function f_level (e) if (c_ball.x==100 && c_ball.y==100) {
gotoAndStop(2);}

Answer 1

MOUSE_UP and MOUSE_DOWN are not what you need if you're looking for Accelerometer data. You want the Accelerometer class and associated events.
Try something like this:
import flash.sensors.Accelerometer;
import flash.events.AccelerometerEvent;
var accel:Accelerometer = new Accelerometer();
accel.addEventListener(AccelerometerEvent.UPDATE, handleAccelUpdate);
Update handler:
function handleAccelUpdate(e:AccelerometerEvent):void{
//inside this function you now have access to acceleration x/y/z data
trace("x: " + e.accelerationX);
trace("y: " + e.accelerationY);
trace("z: " + e.accelerationZ);
//using this you can move your MC in the correct direction
c_ball.x -= (e.accelerationX * 10); //using 10 as a speed multiplier, play around with this number for different rates of speed
c_ball.y += (e.accelerationY * 10); //same idea here but note the += instead of -=
//you can now check the x/y of your c_ball mc
if(c_ball.x == 100 && c_ball.y == 100){
trace("you win!"); //fires when c_ball is at 100, 100
}
}
Now this will let you "roll" your MC off the screen so you're probably going to want to add some kind of bounds checking.
Check out this great writeup for more info:
http://www.republicofcode.com/tutorials/flash/as3accelerometer/

Answer 2

An easy and save way is to use colission detection, instead of testing for exectly one position ( what is hard to meet for users) you go for a target area :
package
{
import flash.display.Sprite;
import flash.events.Event;
import flash.events.MouseEvent;
public class Hittester extends Sprite
{
var ball:Sprite = new Sprite();
var testarea:Sprite = new Sprite();
public function Hittester()
{
super();
ball.graphics.beginFill(0xff0000);
ball.graphics.drawCircle(0,0,10);
testarea.graphics.beginFill(0x00ff00);
testarea.graphics.drawRect(0,0,50,50);
testarea.x = 100;
testarea.y = 100;
// if testarea should be invisble
/*testarea.alpha = 0;
testarea.mouseEnabled = false;
*/
ball.addEventListener(MouseEvent.MOUSE_DOWN, startDragging);
addChild(testarea);
addChild(ball);
}
private function startDragging( E:Event = null):void{
ball.startDrag();
stage.addEventListener(MouseEvent.MOUSE_UP, stopDragging);
}
private function stopDragging( E:Event = null):void{
stage.removeEventListener(MouseEvent.MOUSE_UP, stopDragging);
ball.stopDrag();
test();
}
private function test():void{
if( ! ball.hitTestObject(testarea) ){
ball.x = 10;
ball.y = 10;
}
else{
// here goes next frame command ;)
}
}
}
}