How do I convert keyboard key presses to mouse event clicks?

Hello i am new to this site and actionscript 3, so keep in mind my lack of knowledge. I have code that works fine in actionscript 3, which is what the adobe ios uses to write apps. The only problem is that I don’t know how to change the keyboard presses to button presses. Like in the iphone os a MouseEvent.Click registers when you press down on the screen. How do i change the keyboard presses to mouse clicks? here is the code. Thanks to all who attempt help this noob.

package
{
import flash.display.MovieClip
import flash.events.Event
import flash.events.KeyboardEvent

public class DocumentMain extends MovieClip
{
	public var _player:Player;
	public var _startMarker:StartMarker;
	public var _boundaries:Boundaries;
	private var _vy:Number;
	private var _vx:Number;
	public function DocumentMain():void
	{
		//assign default values
		_startMarker.visible=false; 
		_vx = 0;
		_vy = 0;
		//set focus for keyboard input
		stage.focus=stage;
		
		//add event listeners
		this.addEventListener(Event.ENTER_FRAME, enterFrameHanlder);
		stage.addEventListener(KeyboardEvent.KEY_DOWN, keyDownHandler);
		stage.addEventListener(KeyboardEvent.KEY_UP, keyUpHandler);
	}
	
	private function enterFrameHanlder(e:Event):void
	{
		_vy += 2;
		//gravitate the player
		_player.x += _vx;
		_player.y += _vy;
		
		
		//move the player
				
		//process collisions
		
		processCollisions();
		
		//scroll the stage
		scrollStage();
	}
	
	private function keyDownHandler(e:KeyboardEvent):void
	{
		switch (e.keyCode)
		{
			case 37: //left arrow
			_vx = -7;
			break;
			
			case 38: //up arrow
			_vy = -20;
			break;
			
			case 39: //right arrow
			_vx = 7;
			break;
			
			default:
		}
		
	}
	
	private function keyUpHandler(e:KeyboardEvent):void
	{
		switch(e.keyCode){
			
		
		case 37:
		case 39:
		_vx = 0;
		break;
		
		default:
		
		
		}
	}
	
	private function processCollisions():void
	{
		//when the player is falling
		if( _vy>0)
		{
			//respawn if player fell off the stage
			if(_player.y>stage.stageHeight)
			   {
				    _player.x = _startMarker.x;
				    _player.y = _startMarker.y;
					_boundaries.x = 0;
					_boundaries.y = 0;
					_vy = 0;
			   }
			//otherwise, process collisions with boundaries
			else
			{
				var collision:Boolean=false;
				
			if (_boundaries.hitTestPoint(_player.x, _player.y, true))
			{
				collision = true;
			}
			if (collision)
			{
				while (collision)
				{
					_player.y -=0.1;
					
					collision = false;
					if (_boundaries.hitTestPoint(_player.x, _player.y, true))
			{
				collision = true;
			}
				}
				_vy = 0;
				
			}
			}
			
		}
	}

	private function scrollStage():void
	{
		_boundaries.x += (stage.stageWidth * .5) - _player.x;
		_player.x = stage.stageWidth * .5;
		_boundaries.y += (stage.stageHeight * .5) - _player.y;
		_player.y = stage.stageHeight * .5;
		
	}
}

}