I have a scene that contains a movie clip. That movie clip has a button that controls the y position of a symbol in the scene. What I tried to do is move on to the next scene when the symbol reaches certain y values. I used gotoAndPlay when the desired y position was reached, the new scene was switched to but an error appeared on output as indicated by the title. This is the code that appears in the movie clip:
launch_btn.addEventListener(MouseEvent.CLICK, init_launch)
function init_launch(evt:MouseEvent):void
{
MovieClip(root).launch_video.play();
var k = setTimeout(launch, 1);
}
function launch():void
{
trace(MovieClip(root).rkt.y);
if(MovieClip(root).rkt.y != null)
{
//progressively changing the y position
if(MovieClip(root).rkt.y != null)
{
if(MovieClip(root).rkt.y < 600)
{
MovieClip(root).rkt.y -=0.3
}
if(MovieClip(root).rkt.y < 500)
{
...
}
setTimeout(launch, 1);
if(MovieClip(root).rkt.y < -150)
{
MovieClip(root).gotoAndPlay(1, "Scene 3")
}
}
}
Currently, as compile this code the error points to the line "trace(MovieClip(root).rkt.y);".
What I don't get is why rkt suddenly becomes null when I try to go to a different scene. I tried checking if the property is null but that doesn't help.
I tried removing eventListener, and calling functions that resided in the actions layer of the scene itself (the original one) instead of directly going to the scene from the movie clip.
All in vain.
Any ideas?
What I don't get is why rkt suddenly becomes null when I try to go to a different scene. I tried checking if the property is null but that doesn't help.
It's the object that's null, not the property.
I tried removing eventListener
Which won't help much given that the continuing calls to launch are not triggered by an event but setTimeout which will keep firing.
Stop using setTimeout and use a Timer. This allows you to remove the event listeners properly and actually stop it.
MovieClip(root) was actually the property that turned null when the y position was reached. I modified the condition inside launch() to handle that:
function launch():void
{
if(MovieClip(root)!= null)
{
rest of code...
}
}
I really hope this would help others. I only posted a question here after much research online and particularly here. It appears this error plagues a lot of developers.
Related
I am creating a simple flash coloring book and am not very familiar with as3 programming language.
I entered the following code,and when I attempted to press the back button in the test movie I got that error.
stop();
back_btn.addEventListener(MouseEvent.CLICK, GoToChooseA);
function GoToChooseA(event:MouseEvent):void
{
gotoAndStop("Choose");
}
color_scroll.mask = myMask;
var goY: Number = color_scroll.y;
stage.addEventListener(Event.ENTER_FRAME, scrollManage);
function scrollManage(Event): void {
color_scroll.y += (goY - color_scroll.y) / 20;
}
up_btn.addEventListener(MouseEvent.MOUSE_DOWN, scrollUP);
down_btn.addEventListener(MouseEvent.MOUSE_DOWN, scrollDown);
function scrollUP(MouseEvent): void {
goY += 20;
}
function scrollDown(MouseEvent): void {
goY -= 20;
}
*
It seems to indicate the error is here
color_scroll.y += (goY - color_scroll.y) / 20;
But I'm really bummed because I'm not really sure how to proceed from there.
Whenever you gotoAndStop() to a different keyframe, your current frame is invalidated and all its members destroyed. Listeners persist, if they are attached to an object that persists. So, right after you call GoToChooseA(), your color_scroll is destroyed, and then the listener attached to stage is called and tries to modify a destroyed object, there goes your 1009. The solution is either manually remove the event listeners "scrollManage", "scrollUp", "scrollDown" before you change the frame, at least "scrollManage" because it's attached to stage, or stop using frames altogether, but even then you'll have to control your event listeners.
You could add some logic to your function to check if you are in the right frame and then proceed. I am not familiar with frames so the condition would be something like this._currentframe == 2 or timeline.currentFrame == 2.
function scrollManage(Event): void {
if ( condition ) {
color_scroll.y += (goY - color_scroll.y) / 20;
}
}
If you are not at the right frame (in my example that is frame 2), the function does not execute any code.
This error means you are trying to modify something that is no longer existent.
EDIT: I don't know if this is the norm, but I preferred to leave the original question in and add updates. Please, feel free to let me know if I should eliminate the original code snippets and somesuch.
I am trying to create a slideshow-like presentation in flash CS6, using a main timeline with one symbol in each frame and the different animations (some quite complex) in those symbols. Since I'm going to use a presenter remote, I've captured the keystrokes and coded pg_up and pg_down to go to the next and previous frame respectively:
stage.addEventListener(KeyboardEvent.KEY_DOWN, pagerFunction);
var symb:movieClip;
function pagerFunction(e:KeyboardEvent):void
{
var myKey = e.keyCode;
if (myKey == Keyboard.PAGE_DOWN){
if (symb != null){
//some code that allows to control the symbols timeline forward
} else {
nextFrame();
}
}
if (myKey == Keyboard.PAGE_UP){
if (symb != null){
//some code that allows to control the symbols timeline backward
} else {
prevFrame();
}
}
The problem I'm having is the following. I've added framelabels and stop(); code inside the symbol animations where I needed to control the step from one animation to the next one. However, after having tried numerous solutions on the web, I haven't been able to succeed having the symbols react to pg_up and pg_down as if they were part of the main timeline.
To sum up, what I need to solve is this:
Enter Main timeline Frame
Identify symbol instance (labeled as _mc)
Inside symbol timeline, play from first frame (labeled '0') until next labeled frame ('1' and so on)
stop and wait for next pg_down to start playing from next labeled frame to the following (i.e. '1'-'2'), or pg_up to start playing from the previous labeled frame (i.e. '0' to '1') (for this, I would use a variable to keep track.
on last frame (labeled 'final') exit symbol focus and return keyboard control to main timeline to allow pg_down and pg_up to move to the next / previous frame. on pg_up on symbol.currentFrame == 0, do same.
BTW, if there's a better way to achieve this, I'm open (and quite desperate) for better suggestions / solutions.
Thank you so much to anyone who can help!
Edit: Ok, I guess I wasn't too clear on the issue, so I'll try to add a bit to this:
addEventListener(KeyboardEvent.KEY_DOWN, mc_pagerFunction);
var lbl:String;
var counter:Number = 0;
function mc_pagerFunction(e:KeyboardEvent):void {
var myKey = e.keyCode;
if (myKey == Keyboard.PAGE_DOWN){
lbl = this.currentFrameLabel;
if (this.currentFrameLabel == 'final'){
stop();
stage.focus = this.parent; //which would be the main timeline
} else if (Number(lbl) == counter){
this.gotoAndStop(lbl);
counter++;
} else {
this.gotoAndPlay(lbl);
}
}
if (myKey == Keyboard.PAGE_UP){
lbl = this.currentFrameLabel;
if (this.currentFrameLabel == '0'){
stop();
stage.focus = this.parent; //which would be the main timeline
} else if (Number(lbl) == counter){
this.gotoAndStop(lbl);
counter--;
} else {
this.gotoAndPlay(lbl);
}
}
}
Now, this bit is the behaviour I'd like to see inside the symbol when the main timeline goes into the next frame, thus being able to use the main timeline as sort of slideholder and the real thing happening inside the symbol.
Btw, I'd like to try and keep all code within the main action layer, not in the symbols. I tried that, shifting focus to the symbol and it didn't work either, and having code all over the place grates against my nerves ;).
I hope this throws some light on what I'm stuck at.
Again, any help is appreciated. Thanks all in advance
UPDATE:
Please someone help me out here!
This is what I'm trying. Logically, it makes all the sense in the world, except that it doesn't work.
var symb:MovieClip;
symb = MovieClip(root); //assign symbol I want to be controlled by pg_up/pg_down
symb.focusRect = false;
stage.focus = symb; //focus on current symbol
symb.addEventListener(KeyboardEvent.KEY_DOWN, mc_pager); //add keyboard event listener
function mc_pager(e:KeyboardEvent):void{
var myKey = e.keyCode;
if (myKey == Keyboard.PAGE_DOWN){
do{
symb.play(); // it plays, then checks if the lbl is null or final, then quits
} while (symb.currentFrameLabel == null && symb.currentFrameLabel != 'final');
symb.stop();
symb.removeEventListener(KeyboardEvent.KEY_DOWN, mc_pager);
stage.focus=MovieClip(root); //return focus to main timeline (in the next keyframes, the focus is on the nested _mc
}
if (myKey == Keyboard.PAGE_UP){
do{
symb.prevFrame();
} while (symb.currentFrameLabel == null && symb.currentFrameLabel != '0');
symb.stop();
symb.removeEventListener(KeyboardEvent.KEY_DOWN, mc_pager);
stage.focus=MovieClip(root);
}
}
Where am I being to moronic to get it right? Please, guys, you're the experts, I need your advice here. Thanks!
UPDATE:
Doing a trace on symb, it seems like as soon as it enters the function, it forgets the initial assignment (symb = MovieClip(root)) and shows null. Why?
In this sample, I created a basic proof of concept where I have a circle MC with an instance name of "c" on the main timeline. Within this mc, I created with 2 keyframes inside with stop actions on both. I colored the circle a different color on frame 2 and labeled it as "two".
In the Main timeline I have the following code:
import flash.events.KeyboardEvent;
stage.addEventListener(KeyboardEvent.KEY_DOWN,keyEvt);
function keyEvt(e:KeyboardEvent):void{
if(e.keyCode == Keyboard.PAGE_DOWN){
trace("down");
c.gotoAndPlay("two");
}
}
This should help form a foundation for your code as long as you stick with targeting the symbol through direct reference and ensure your keyboard event is attached to the stage.
Also, always stick with getting a basic working version down first. I.E. Check to see if your keyboard listeners are working for your target object and then build additional functionality off of that.
I'm creating a quiz with buttons and I'm new to ActionScript 3.0, but very familiar with 2.0.
I have a variable inside of a MC called NextQuestion. When it reaches a certain frame, it changes to 1, then back to 0.
On the main timeline, when NextQuestion == 1, it's supposed to NextFrame();. I can't get it to work though, this is the last thing I'm having trouble with.
This is my main code with 4 buttons, 3 wrong, 1 right. The feedback MC plays an animation, and when it finishes, it sets the VAR NextQuestion to 1, which is supposed to make the main timeline advance to the NextFrame.
stop();
right.addEventListener(MouseEvent.CLICK, rightClick1);
wrong1.addEventListener(MouseEvent.CLICK, wrongClick1);
wrong2.addEventListener(MouseEvent.CLICK, wrongClick1);
wrong3.addEventListener(MouseEvent.CLICK, wrongClick1);
feedback1.addEventListener(Event.ENTER_FRAME, answerRight1);
function answerRight1()
{
if (feedback1.NextQuestion == 1)
{
trace(feedback1.NextQuestion);
nextFrame();
}
else
{
trace("do nothing");
}
}
function rightClick1(ev:MouseEvent):void
{
trace(feedback1.NextQuestion);
feedback1.gotoAndPlay("right1");
}
function wrongClick1(ev:MouseEvent):void
{
trace("wrong");
feedback1.gotoAndPlay("wrong");
}
Any help is greatly appreciated! :)
The nextFrame() method in AS3 doesn't loop trough your movieClips, it just set's the movie clip to the next frame provided there is a next frame, otherwise it does nothing.
you might want to re-write the nextFrame() to:
if (totalFrames == currentFrame)
{
gotoAndStop(1); // or gotoAndPlay(1) if you need
}
else
{
nextFrame();
}
Thats regarding why the movie clip might not start from the beginning.
Another thing that look weird is that you need a FRAME_ENTER event to check if the answer is correct. You must have a lot of spam in the output log. I'd recommend you to totally ditch the ENTER_FRAME event listener for this and do it all with the CLICKED event and dispatching the event from the feedback1 object.
As much as I understand the movie clip plays when you click a button and when the animation is over you want to either progress to next frame or do nothing. If so, on the feedback1 object add a following line in the end of animation for label "right1":
dispatchEvent(new Event("right"));
and instead of the line feedback1.addEventListener(Event.ENTER_FRAME, answerRight1); have:
feedback1.addEventListener("right", answerRight1);
That way you won't need to check the answer on every frame and you don't need to check if the answer is right or not, because when the dispatchEvent(new Event("right")); fires - it's always right.
Hope I didn't misunderstand your question :)
Ok, so I'm a beginner at AS3 and Flash and I managed to put this code together for an animation. A Button called start_btn is supposed to start and stop a movieclip called main_mc. On the first click of the Button, the Movieclip is supposed to play (which it does), however on the second click, the movie stops in the middle of its animation (which I don't want). My question is, when you click the Button a second time, how can i get the Movieclip to finish playing its animation then stop on the last frame?
I thought about using if (main_mc.currentFrame == main_mc.totalFrames); {main_mc.stop(); but the Movieclip still does not stop on the last frame. The Movieclip itself also has a gotoAndPlay(2); command on the last frame so that the animation repeats before the Button is clicked a second time.
here is the code i have:
`start_btn.addEventListener(MouseEvent.CLICK, mainaniS);
function mainaniS(event:MouseEvent):void
{
main_mc.play();
start_btn.removeEventListener(MouseEvent.CLICK, mainaniS);
start_btn.addEventListener(MouseEvent.CLICK, mainaniSt);
}
function mainaniSt(event:MouseEvent):void
{
if (main_mc.currentFrame == main_mc.totalFrames);
{main_mc.stop();}
start_btn.removeEventListener(MouseEvent.CLICK, mainaniSt);
start_btn.addEventListener(MouseEvent.CLICK, mainaniS);
}`
Try main_mc.gotoAndStop(main_mc.totalFrames).
I was going to provide a quick and dirty solution, but decided instead to try and explain a few of the issues with your current implementation and attempt to refactor and explain and better one. Unfortunately I don't have access to Flash right now, so the code is untested.
You're adding and removing event listeners often, which is generally a bad idea. Instead, since you're using a single button to perform multiple functions it would make sense to track the button state in a separate variable. In this case, a boolean for whether or not the movieclip is currently playing.
var playing:Boolean;
Now we can combine the mainaniS and mainaniSt into one and perform a different action based on whether or not the movieclip is playing, and just keep the one eventlistener on the button. I've also taken the liberty of naming the method something more meaningful:
start_btn.addEventListener(MouseEvent.CLICK, onStartClick);
function onStartClick(event:MouseEvent):void
{
if(playing) {
playing = false;
}
else {
playing = true;
main_mc.play();
}
}
You may be wondering why we don't call main_mc.stop() in the first block: the reason is that you don't want to stop the movieclip as soon as you click the button, but after the movieclip has finished playing if the button has been clicked. Therefore, we just set playing to false to indicate that we want it to stop later.
Finally, we need to make sure the movieclip stops upon completion, but only if playing is false. To do this we add a listener to movieclip that is called every frame, and checks whether playing is false, and if it's on the last frame. Note that the last frame is actually totalFrames - 1: this is because the frame numbers start from zero rather than one (i.e. if totalFrames is 3, the frame numbers will be 0, 1, 2).
main_mc.addEventListener(Event.ENTER_FRAME, animate);
function animate(event:Event):void {
if(!playing && main_mc.currentFrame == main_mc.totalFrames - 1) {
main_mc.stop();
}
}
All the refactored code together:
var playing:Boolean;
start_btn.addEventListener(MouseEvent.CLICK, onStartClick);
main_mc.addEventListener(Event.ENTER_FRAME, animate);
function onStartClick(event:MouseEvent):void
{
if(playing) {
playing = false;
}
else {
playing = true;
main_mc.play();
}
}
function animate(event:Event):void {
if(!playing && main_mc.currentFrame == main_mc.totalFrames - 1) {
main_mc.stop();
}
}
My flash game exists of a timeline with multiple frames (I know I should avoid the timeline)
The point of the game is a point and click adventure. The object that you are able to pick up get spawned and destroyed accordingly as you enter and leave the room. now my problem is when entering frame 14 (accessibel from frame 12) it creates a piece of paper which you are able to pick up if you have another item. Now my problem is when you can't or don't pick up the paper and go back to frame 12 (only exit is to frame 12), you can't click on any other object and you are basicly stuck on frame 12. When leaving and entering other rooms it works properly but for some reason it doesn't for on the paper on frame 14.
My code to remove objects works as following
In my Main.as Documentclass I have a function that called as soon as the game starts which does the following
if (lastframe == 14)
{
trace (prop.numChildren);
while (prop.numChildren )
{
prop.removeChildAt(0);
}
}
The lastframe variable is established when moving from frames
this function is found on the frame itself (each exit function on it's own respective frame)
function exitKantine(event:MouseEvent):void
{
Main.lastframe = 14;
gotoAndStop(12);
}
The function to remove the prop actually removes it but then causes all other clickable objects to be unusable.
Thanks for looking at my question and thanks in advance for your suggestions
I would say instead of removing children, add it once in the beginning, add all the listeners in the beginning, and toggle the visibility instead of trying to addChild and removeChild every time you want to hide it. Use an array so you can have a few happening at the same time.
something like this:
private function init():void
{
assignVars();
addListeners();
stage.addChild // make sure this is in document class or you are passing stage to the class using it
}
for (var i = 0; i < _thingsAry.length; i++)
{
if (_thingsAry[i] == 14)
{
_thingsAry[i].visible = false;
trace("the visibility of _thingsAry[" + i + "] is " + _thingsAry[i].visible
}
}