actionscript 3 - AS3 error 1061 trying to get collision -

" player.as, line 59 1061: call possibly undefined method hittestobject through reference static type class."

i new flash , trying make game, trying make player class in game can collide things, using square @ bottom of feet (not yet referenced in code) , movieclip called collisiontest

package {     import flash.display.stage;     import flash.display.movieclip;     import flash.events.event;     import keyobject;      public class player extends movieclip     {         public var stageref:stage;         public var key:keyobject;          //add these 4 variables:         public var leftpressed:boolean = false; //keeps track of whether left arrow          key pressed         public var rightpressed:boolean = false; //same, right key pressed         public var uppressed:boolean = false; //...up key pressed         public var downpressed:boolean = false; //...down key pressed          private var gravity:number = 2;         private var runspeed:number = 5;          private var touchingground:boolean = false;          public var vpressed:boolean = false;          public function player(stageref:stage, x:int, y:int):void         {             this.stageref = stageref;             this.x = x;             this.y = y;              key = new keyobject(stageref);              addeventlistener(event.enter_frame, loop, false, 0, true);         }          public function loop(e:event):void         {             checkkeypresses(); //call "checkkeypresses()" every frame             checkcollisions();              if(leftpressed)             {                 x -= runspeed;             }else if(rightpressed)             {                 x += runspeed;             }             if(uppressed)             {                 y -= runspeed;             }else if(downpressed)             {                 y += runspeed;             }         }         public function checkcollisions():void         { **(this line 59)**           if(player.hittestobject(player.collisiontest)){                 touchingground = true;                 trace("gounded");             }         }          public function checkkeypresses():void         {             // used http://www.dakmm.com/?p=272 reference keycode numbers each key             if(key.isdown(37) || key.isdown(65)){ // if left arrow or pressed                 leftpressed = true;                 //trace("left pressed");             } else {                 leftpressed = false;             }              if(key.isdown(38) || key.isdown(87)){ // if arrow or w pressed                 uppressed = true;                 //trace("up pressed");             } else {                 uppressed = false;             }              if(key.isdown(39) || key.isdown(68)){ //if right arrow or d pressed                 rightpressed = true;                 //trace("right pressed");             } else {                 rightpressed = false;             }              if(key.isdown(40) || key.isdown(83)){ //if down arrow or s pressed                 downpressed = true;                 //trace("down pressed");             } else {                 downpressed = false;             }         }     } } 

function hittestobject isn't static function, should call object instance, same collisiontest.

so should be

this.hittestobject(collisiontest);//set collisiontest in player class