Flash Tutorials - FAQ

Question: The keyboard control works in flash but doesnt work on the web page?

Answer: For keyboard controlled games you need to ensure that the flash file has the focus, otherwise the keypresses wont be detected. This short tutorial explains two techniques. How to ensure that the flash file has the focus

Q: Is there a printer friendly version of your tutorial?

A: Yes its here

Q: There is a typo/bug in the version of the tutorial on flash kit!

A: yea I know, the flash kit guys dont seem to have time to change it - send them an email and give them a nudge. The version on this site has the typo fixed.

Updated version of the fla: Ive put together an updated version of the fla that answers all of the following four questions in one go!

Q: How do I keep the player from moving off the stage?

A: In the updated version the player cant move off to the left
top or bottom of the stage. The if statments for the player movement in the spacehip clipEvent have been changed to prevent movement off the stage.

Q: How do I add lives to the game?

A: In the updated version of the game the player now has 5 lives and loses a life when colliding with an enemy spaceship.
When all 5 lives are lost the game ends.
To change the number of lives change the value assigned to the lives variable in the actionscript for the first frame.
ie: change the line
lives = 5;

Two new functions are included in the first frame. These are : loseLife and resetAllEnemies.
The loseLife function is called when the player collides with a enemy.

The loseLife function reduces the players life by one. If the player has no lives left then the game Over frame is displayed.

function loseLife () {
resetAllEnemies();
lives--;
if (lives<=0) {
     gotoAndStop ("gameOver");
}
}

function resetAllEnemies () {
 // this function resets all of the enemies
 for (i=1; i<=numEnemy; i++) {
     this["enemy"+i].reset();
}
}

Q: How do I add levels to the game

A: The updated version has levels, a new level starts when the player has shot 8 enemies.
The code for counting the enemies shot is in the laser movie clip's onClipEvent(enterFrame) code.
The function newLevel() below is called when all 8 enemies are shot.
The newLevel function increases the level number and creates one new enemy.

function newLevel() {
// This function is called when a new level starts
// it increases the level number and adds one new enemy

level++;
numEnemy++;
enemy1.duplicateMovieClip("enemy"+numEnemy, numEnemy+100);
resetAllEnemies();

}

Q: How do I stop the player from getting points from hitting the exploding enemy.

A: In the updated version the player no longer gets points from the lasers hitting the enemy explosion.This is achieved by adding a new varaible hitFlag which is set to true once the enemy ship has been hit by a laser.

Q: How do I make a platform game?

A: I wrote a case study on platform games for the book flash games studio - more info here.

Q. How do I make everything scroll down instead of sideways?

A: Ive put together a version of the final fla that shows how to do this.
Basically it involves changing the code for the stars to scroll down:

onClipEvent (load) {

	stars.duplicateMovieClip("stars2", 1000);
	stars2._y = stars._y-stars._height;
	starsStartY = this._y;
	starsSpeed=4;

}

onClipEvent (enterFrame) {

if (_root.spaceship.scrollStart){
	this._y+=starsSpeed;
	if (this._y>= (starsStartY+stars._height)){
		this._y=starsStartY+starsSpeed;
	}
}

}

and then changing the spaceship, ground, enemy movement and laser movement code.