I have a student who is working on a Tower Defense game in AS3 and has an issue that has stumped me. He is using hitTestObject to change the direction that a movieClip is moving. The movieClip has its own timeline with frames for the different directions that the object is facing and a linked .as file with the code for the behavior of the object.
When he calls gotoAndStop to change the internal frame of the movieClip, the removed event is triggered, but the object stays on the screen and no longer moves.
All of my searches find answers about removing objects, but I have not seen anything about preventing an object from removing itself.
The following code is a loop triggered by an ENTER_FRAME event in the .as class file for the movieClip object:
private function eFrame(event:Event):void
{
if (_root.isPaused == false)
{
//MOVING THE ENEMY
this.x += speed * xDir;
this.y -= speed * yDir;
if (health <= 0)
{
_root.currency += 4;
this.parent.removeChild(this);
}
if (this.x > 770)
{
this.parent.removeChild(this);
_root.health -= 10;
_root.gotHit = true;
}
//checking if touching any invisible markers
for (var i:int=0; i<_root.upHolder.numChildren; i++)
{
//the process is very similar to the main guy's testing with other elements
var upMarker:DisplayObject = _root.upHolder.getChildAt(i);
if (hitTestObject(upMarker))
{
yDir = 1;
xDir = 0;
this.gotoAndStop(3);
}
}
for (i=0; i<_root.downHolder.numChildren; i++)
{
//the process is very similar to the main guy's testing with other elements
var downMarker:DisplayObject = _root.downHolder.getChildAt(i);
if (hitTestObject(downMarker))
{
yDir = -1;
xDir = 0;
this.gotoAndStop(7);
}
}
for (i=0; i<_root.rightHolder.numChildren; i++)
{
//the process is very similar to the main guy's testing with other elements
var rightMarker:DisplayObject = _root.rightHolder.getChildAt(i);
if (hitTestObject(rightMarker))
{
yDir = 0;
xDir = 1;
this.gotoAndStop(6);
}
}
for (i=0; i<_root.leftHolder.numChildren; i++)
{
//the process is very similar to the main guy's testing with other elements
var leftMarker:DisplayObject = _root.leftHolder.getChildAt(i);
if (hitTestObject(leftMarker))
{
yDir = 0;
xDir = -1;
this.gotoAndStop(2);
}
}
}
}
private function remove(event:Event):void
{
trace("remove");
removeEventListener(Event.ENTER_FRAME, eFrame);
_root.enemiesLeft -= 1;
}
}
When the gotoAndStop line executes, the frame of the movieClip changes and then the code jumps directly to a function that is triggered by the REMOVED event.
Does anyone have an idea why the REMOVED event might be triggered by this code?
Thank you for your help.
The REMOVED Event is triggered by anything that is removed from the stage inside the MovieClip or Sprite that is containing it, if I'm not mistaken. And especially with MovieClips that have animation, things get removed and added everytime, for instance if some part of the animation ends on the timeline, or at keyframes.
Event.REMOVED_FROM_STAGE is dispatched only when the container itself is removed from stage. Maybe that's causing your confusion? I can't see from your code example exactly what event type you're listening for.
Where are you adding the remove-listener?
Without more information, I would guess that you are listening to a clip inside an animation, and that it's not there on all frames (or, maybe even more likely - that the instance is being swapped out for another, identical one, by flash pro. This can happen depending on in what order you added keyframes, the alignment of the moon and fluctuations in the ionosphere. It's easiest fixed by simply removing all key-frames and then re-creating them. And then never using flash pro for anything ever again.)
Related
I have this baffling problem with Flash AS3 that I have been attempting to solve for a long time. I have a notion that perhaps this is a bug with the flash player, but perhaps you can shed some insight.
I have a MovieClip in Flash that is a star for 10 frames, a circle for another 10, and then a square for another 10, after which it will gotoAndPlay(1), replaying the animation. This MovieClip extends an AS3 class I have called FlipClip.
FlipClip has a function in it called reverseClip. This function's purpose is to flip certain graphic children around an axis every time Flash launches the EXIT_FRAME event.
public function FlipClip()
{
//as soon as this is instantiated, add the eventListener
addEventListener(Event.EXIT_FRAME,flipTheClip);
}
public function flipTheClip(e:Event)
{
trace("currentFrame = " + currentFrame);
//for sake of simplicity, we will flip every child
for (var i=0; i<numChildren; i++)
{
var targetClip = getChildAt(i);
var axis = 10;
//if the target child has not already been flipped...
if (Math.abs(targetClip.scaleX) / targetClip.scaleX != -1)
{
//reverse the child's direction with scaleX and move based on the axis
targetClip.scaleX *= -1;
var dist:Number = targetClip.x - axis;
targetClip.x = axis - dist;
}
}
}
The obvious outcome is that every time we exit a frame, all of the graphic elements are flipped horizontally around x=10, and every ten frames the shape of the MovieClip changes from a star, to a circle, to a square. Right?
Nope.
The MovieClip does successfully flip around that axis, but then a strange problem occurs. The animation stops. The MovieClip is stuck as an eternal star. And Flash doesn't even recognize that the animation has stopped, as we get this output over and over;
currentFrame = 1
currentFrame = 2
currentFrame = 3
currentFrame = 4
...
currentFrame = 30
currentFrame = 1
All the way up to 30, at which point it goes back to one. The clip is still playing, but somehow the graphic elements are not updating!
Is this a problem with the flash player? Is this a problem with the code? Any help is appreciated!
I've uploaded the files for the .fla and .as on dropbox. I'm still figuring out how to embed something like that, but for now I'm gonna hope this link works for you.
https://www.dropbox.com/sh/hcljutesblichpp/AABKQ4Kn8OTwfTaeh0I3nnOZa?dl=0
UPDATE:
If I convert every individual shape into a MovieClip within the parent MovieClip, it plays correctly. However, this is not very memory efficient or feasible with complex animations. Hopefully this bit of information can help you solve the problem.
There are couple of thing which you need to take care.
You don't need to flip element based on the numChildren as it always
return 1 as on each frame you will get single children.
you also don't need to do the check another condition
Math.abs(targetClip.scaleX) / targetClip.scaleX != -1 to set the
flip.
And also you need to use ENTER_FRAME instead of EXIT_FRAME.
ENTER_FRAME works for the current frame whereas EXIT_FRAME works for
previous frame.
Use the below code.
package
{
import flash.display.MovieClip;
import flash.events.*;
import flash.utils.setTimeout;
public class FlipClip extends MovieClip
{
var mInstance
var prevX;
public function FlipClip()
{
//as soon as this is instantiated, add the eventListener
addEventListener(Event.ENTER_FRAME,flipTheClip);
mInstance = this;
//mInstance.visible = false;
}
public function flipTheClip(e)
{
this.scaleX *= -1;
prevX = this.x;
if(this.scaleX < 0)
this.x = prevX + this.width
else
this.x = prevX - this.width
}
}
}
Paste above code in FlipClip.as file and change the frame rate to 1.
You need to update the moviClip placement based on your requirement.
Hope above answer solve your problem.
You need to remove listener for EXIT_FRAME before playing animation. Also you are Flipping your movieClip here but not adding any code for playing it.
Paste below code in your FlipClip.as file.
package
{
import flash.display.MovieClip;
import flash.events.*;
import flash.utils.setTimeout;
public class FlipClip extends MovieClip
{
var mInstance
public function FlipClip()
{
//as soon as this is instantiated, add the eventListener
addEventListener(Event.EXIT_FRAME,flipTheClip);
mInstance = this;
mInstance.visible = false;
}
private function playallAnimation()
{
this.gotoAndPlay(1);
}
public function flipTheClip(e)
{
removeEventListener(Event.EXIT_FRAME,flipTheClip);
//for sake of simplicity, we will flip every child
for (var i=0; i<numChildren; i++)
{
var targetClip = getChildAt(i);
var axis = 10;
//if the target child has not already been flipped...
if (Math.abs(targetClip.scaleX) / targetClip.scaleX != -1)
{
//reverse the child's direction with scaleX and move based on the axis
targetClip.scaleX *= -1;
var dist:Number = targetClip.x - axis;
targetClip.x = axis - dist;
}
}
setTimeout(function()
{
mInstance.visible = true;
playallAnimation();
},200);
}
}
}
Hope this will work for you.
I've spent 14 hours on this problem. This is a basic collision checker that sets a MovieClip animation to play when a collision occurs. The clip is
currentBallObject.clip.
It works. The clips plays. But it repeats over and over.
private function checkCollisions():void
{
var i = balls.length;
while (i--)
{
var currentBallObject = balls[i];
if (currentBallObject.contact)
{
//condition hits ground
if (currentBallObject.ground)
{
currentBallObject.body.SetPosition(new b2Vec2(currentBallObject.startX / PIXELS_TO_METRE, currentBallObject.startY / PIXELS_TO_METRE));
currentBallObject.body.SetLinearVelocity(new b2Vec2(0, 0));
currentBallObject.body.SetAngularVelocity(0);
//currentBallObject.texture.pop();
}
else // it hit player
{
// assign clip texture to current position
currentBallObject.clip.x = currentBallObject.body.GetPosition().x * PIXELS_TO_METRE;
currentBallObject.clip.y = currentBallObject.body.GetPosition().y * PIXELS_TO_METRE;
// whisk old object away
currentBallObject.body.SetPosition(new b2Vec2(currentBallObject.startX / PIXELS_TO_METRE, currentBallObject.startY / PIXELS_TO_METRE));
currentBallObject.body.SetLinearVelocity(new b2Vec2(0, 0));
currentBallObject.body.SetAngularVelocity(0);
currentBallObject.contact = false;
}
}
}
}
I added this code to delete the MovieClip or somehow get rid of it after it has played through once. (42 frames). I also tried to add a frameListener and at least a dozen other suggestions. When I add
stop()
The animation doesn't play. It just loads the last frame. The code I have now is:
private function updateClips():void
{
var i = balls.length;
while (i--)
{
var currentBallObject = balls[i];
if(currentBallObject.clip)
{
var frame:int = currentBallObject.clip.currentFrame;
//trace(currentBallObject.clip.currentFrame);
if(frame == 42)
{
currentBallObject.clip._visible = false;
currentBallObject.clip.removeMovieClip();
currentBallObject.clip.enabled = -1;
}
}
}
}
I've tried counting the frames, putting it a run-once function, a frame exit listener, I am out of ideas. I just want to make a MovieClip run one time through. I also tried putting stop() in the timeline and then the animation didn't play. It just loaded the last frame.
Right now the collisions work but the animations stay on the screen forever, looping forever.
Edit: I got the code by Patrick to run without errors.
I added the event listener with the others like this:
_input = new Input(stage);
...
addEventListener(Event.ENTER_FRAME, oEF);
addEventListener(Event.ENTER_FRAME, update);
time_count.addEventListener(TimerEvent.TIMER, on_time);
time_count.start();
}
And then created a function:
private function oEF(e:Event):void{
var i = balls.length;
while (i--)
{
var currentBallObject = balls[i];
if (currentBallObject.clip.currentFrame >= currentBallObject.clip.totalFrames)
{
currentBallObject.clip.stop();
currentBallObject.clip.removeEventListener(Event.ENTER_FRAME, oEF);
if (currentBallObject.clip.parent) currentBallObject.clip.parent.removeChild(currentBallObject.clip);
}
}
}
But I still get the same problem as any other result. The MovieClip disappears on contact without the animation happening.
Through debugging I've learned more. The value of currentFrame starts off going 1-40 then stays at 40 for the rest of the execution.
So the MovieClip is always on the last frame for every object.
if clip is a MovieClip then you can use clip.totalFrames in an enterframe listener.
function oEF(e:Event):void{
if (this.currentFrame >= this.totalFrames){
this.stop();
this.removeEventListener(Event.ENTER_FRAME, oEF);
if (this.parent) this.parent.removeChild(this);
}
}
this.addEventListener(Event.ENTER_FRAME, oEF);
I figured it out.
if (currentBallObject.clip.currentFrame == currentBallObject.clip.totalFrames)
{
trace("Frame before kill: ", currentBallObject.clip.currentFrame);
currentBallObject.clip.x = 0;
currentBallObject.clip.y = 0;
}
The above block goes right after
var currentBallObject = balls[i];
It checks if the movieClip is on the last frame and then gets rid of the clip by setting clip.x & clip.y to 0. I could find no other way to stop the movie in this particular case.
Hey guys I am having a problem with Event Listeners in my AS3 file. I am trying to make this object that lasts for 83 frames to appear in a different location every time the parent (83 frame) movie clip resets. The problem is I have a function that places the object at a random y value which works great once. When it resets the ojbect appears on the same Y point. This is because I removeEventListener the function otherwise the object goes shooting off the screen when it loads. How do I call that event listener again without causing a loop that will shoot the object off screen?
Here is my code:
import flash.events.Event;
stop();
addEventListener(Event.ENTER_FRAME, SeaWeedPostion);
//stage.addEventListener(Event.ADDED_TO_STAGE, SeaWeedPostion);
function SeaWeedPostion(e:Event):void{
// if(newSeaWeed == 1) {
var randUint:uint = uint(Math.random() *500 + 50);
this.seaweedSet.y += randUint;
trace(randUint);
stopPos();
//}else{
//nothing
// }
}
function stopPos():void{
removeEventListener(Event.ENTER_FRAME, SeaWeedPostion);
//var newSeaWeed = 0;
}
function resetSeaWeed():void{
addEventListener(Event.ENTER_FRAME, SeaWeedPostion);
}
I have some // code in there from trying different things.
Anyone have any suggestions?
Thanks!
ENTER_FRAME event is triggered every frame, so rather than changing position on each frame maybe it's better to create a counter, count frames and if it reaches 82 change position of SeaWeed.
var counter:uint = 0;
Now add ENTER_FRAME listener
addEventListener(Event.ENTER_FRAME, onEnterFrame);
function SeaWeedPostion(e:Event):void {
counter++;
//Are we there yet?
if(counter < 83) {
//Nope, carry on
}
else {
//Yey!
changePosition();
counter = 0;
}
}
//Reset SeaWeed position when called
function changePosition() {
var randUint:uint = uint(Math.random() *500 + 50);
this.seaweedSet.y += randUint;
trace(randUint);
}
I am making a game where insects from above the screen move downwards to the bottom. The object is for the player to kill these insects with his/her mouse. When killed the insect should show a kill frame, where I have put in. The kill frame will stay there for 3 seconds and the object will be removed. This will also increase the player's score.
This code is written inside the insect:
function kill(event:MouseEvent):void
{
this.dead = true;
}
This code is written inside the background movieclip frame.
function moveEnemies():void
{
var tempEnemy:MovieClip;
for (var i:int =enemies.length-1; i>=0; i--)
{
tempEnemy = enemies[i];
if (tempEnemy.dead)
{
tempEnemy.gotoAndStop(21);
var myTimer:Timer = new Timer(3000);
myTimer.addEventListener(TimerEvent.TIMER, timerListener);
myTimer.start();
}
}
}
function timerListener (e:TimerEvent):void
{
for (var i:int =enemies.length-1; i>=0; i--)
{
if (tempEnemy.dead)
{
score++;
roachLevel.score_txt.text = String(score);
removeEnemy(i);
}
}
}
function removeEnemy(id:int)
{
removeChild(enemies[id]);
enemies.splice(id,1);
}
The problem that I am experiencing with this, is that whenever I click on the insects they stay there. I click on another one it stays there. Then another, then after a while they disappear and the score increases. Sometimes the death frame doesn't appear and they die as soon as I touch them. Could you please tell me how I can solve this?
You have to relocate score adding to enemy class, and assign a timeout to the particular squished enemy instead of the base class. The best place to do it is in kill() function.
function kill(e:MouseEvent):void {
this.dead=true;
gotoAndStop(21);
flash.utils.setTimeout(removeSelf,3000);
}
function removeSelf():void {
this.parent.removeChild(this);
}
Now, adjust the mechanics for scoring and tracking objects. First, if an object becomes dead, you immediately remove it from the array of enemies (it will handle its removal on its own) and give score for it. And second, all the other functional should be preserved.
for (var i:int=enemies.length-1;i>=0;i--) {
var tempEnemy=enemies[i];
if (tempEnemy.dead) {
score++;
enemies.splice(i,1);
} else {
tempEnemy.y++; // or other move function
}
}
This loop should be in an enterframe listener, so it'll be called once per frame. Also combining splicing and moving like here eliminates the need of placing movement code elsewhere, as you iterate through the array anyway.
I have a class Catcher which lets you control a movieclip in a game. I'm trying to program the game so it finishes and you can restart. So I need to remove everything and go back to the menu. Should be a simple thing to solve but I can't seem to find out how.
So far I just have ourCatcher.parent.removeChild(ourCatcher); to remove my movieclip from the stage. And an if statement to stop one of the functions which drops things onto the stage. SoundMixer.stopAll(); to stop the music.Then I just have it going to frame 3 which is the gameover screen.
It looks fine but I get constant 1009 errors overflowing in the error console and when I restart the game, it's super slow. It seems the function for movement within Catcher is still running and creating an error because the Catcher was removed from stage and is null now.
I know I need to un-reference everything to do with the Catcher but I can't find out any documentation online to do it in my situation. Everyone seems to have different methods which I've tried and don't work.
The two functions in the Catcher class I'm using to move the character :
public function Catcher(stageRef:Stage)
{
stop();
this.stageRef = stageRef;
key = new KeyObject(stageRef);
addEventListener(Event.ENTER_FRAME, loop, false, 0, true);
}
//movement
public function loop(e:Event):void
{
if (key.isDown(Keyboard.A))
vx -= walkSpeed;
else if (key.isDown(Keyboard.D))
vx += walkSpeed;
else
vx *= friction;
//update position
x += vx;
//speed adjustment
if (vx > maxspeed)
vx = maxspeed;
else if (vx < -maxspeed)
vx = -maxspeed;
//stay inside screen
if (x > stageRef.stageWidth)
{
x = stageRef.stageWidth;
vx = -vx
}
else if (x < 0)
{
x = 0;
vx = -vx;
}
if (key.isDown(Keyboard.A))
{
scaleX = -1;
}
else if (key.isDown(Keyboard.D))
{
scaleX = 1;
}
movement();
// Jumping
jump += gravity;
if (y > stage.stageHeight /1.5)
{
jump = 0;
canJump = true;
}
if (key.isDown(Keyboard.SPACE) && canJump)
{
jump = -10;
canJump = false;
}
y += jump;
}
The other class where I'm removing the things from the stage is called CatchingGame and it has a function which drops objects, I put the game over code there for when playerlives == 0 .
if (playerLives == 0 )
{
stop();
ourCatcher.parent.removeChild(ourCatcher);
SoundMixer.stopAll();
gotoAndStop(3);
}
I've probably made an elementary mistake since this is my first flash game. Any help is greatly appreciated as this is pretty much the last step in finishing my game.
Instead of just removing the child by referencing its parent to remove itself (I had to test to make sure this actually worked). Create a function in same place that you create/instantiate the Catcher that removes first the eventListener ENTER_FRAME, then removes the Catcher.
if (playerLives == 0 ) {
stop();
removeCatcher();
SoundMixer.stopAll();
gotoAndStop(3);
}
// new location in the main code where the catcher is created
function removeCatcher():void {
ourCatcher.cleanUp();
removeChild(ourCatcher);
}
// in the Catcher class
function cleanUp():void {
removeEventListener(Event.ENTER_FRAME, loop);
}
if (ourCatcher.parent) ourCatcher.parent.removeChild(ourCatcher);
else trace("Catcher without a parent still plays! DEBUG THIS!");
Basically, you are most likely losing control flow of your catcher, that is, it seemingly tries to remove itself from the stage twice. After it removes itself first time, its parent becomes null, hence the 1009. And, seeing as you've hit a 2028, the same reason applies, your catcher is no longer a child of anywhere.