Hi i’ve been searching a lot of forums for a solution to this problem but i still cannot figure it out .
here is my code
package
{
import flash.events.*
import flash.display.*
public class Control extends MovieClip
{
private var leftKey:Boolean = false
private var rightKey:Boolean = false
private var upKey:Boolean = false
private var downKey:Boolean = false
private const SPEED:int = 5
private function keyPressed(event:KeyboardEvent):void
{
if(event.keyCode == 37)
{
leftKey = true;
trace("number 37 pressed")
}
if(event.keyCode == 39)
{
rightKey = true;
}
if(event.keyCode == 38)
{
upKey = true;
}
if(event.keyCode == 40)
{
downKey = true;
}
}
private function keyReleased(event:KeyboardEvent):void
{
if(event.keyCode == 37)
{
leftKey = false;
}
if(event.keyCode == 39)
{
rightKey = false;
}
if(event.keyCode == 38)
{
upKey = false;
}
if(event.keyCode == 40)
{
downKey = false;
}
}
private function moveStudent():void
{
if(leftKey == true)
{
targetObject.stage.x -= SPEED
trace("key down ")
}
if(rightKey == true)
{
targetObject.stage.x += SPEED
}
if(upKey == true)
{
targetObject.stage.y -= SPEED
}
if(downKey == true)
{
targetObject.stage.y += SPEED
}
}
public var targetObject:DisplayObject
private function go(event:Event):void
{
trace("go")
}
public function Control(object:DisplayObject)
{
targetObject = object
stage.addEventListener(Event.ADDED_TO_STAGE, go)
stage.addEventListener(KeyboardEvent.KEY_DOWN, keyPressed)
//object.addEventListener(KeyboardEvent.KEY_UP, keyReleased)
//object.addEventListener(Event.ENTER_FRAME, moveStudent)
//keyPressed();
//keyReleased();
moveStudent();
}
}
}
everything is fine except stage.addEventListener…etc
because of these two lines im getting error
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at Control()
at DragGame()
at dropstop_fla::MainTimeline/frame1()
i’ve tried to figure it out with my lecturer but he couldn’t hep me with this one,does it have to do anything with ADDED_TO_STAGE event?just a guess.really desperate for solving this issue, thanks for any help
