Actionscript 3: gotoAndStop - actionscript-3

I have a project in Flash CS3 that's giving me a bit of trouble. I have a movieclip, and in that movieclip, I have a button. The movieclip is named bg and the button tohallway_btn. My coding is on the stage on a layer, not on classes or in a package, or anything of that sort. This is my coding:
bg.tohallway_btn.addEventListener(MouseEvent.CLICK, tohallwayClick);
function tohallwayClick(event:MouseEvent):void{
gotoAndStop (141);
}
It seems simple enough, yet when I debug and the button is clicked, the flash player freezes over. I have absolutely no idea what's causing it to do this.
I get a type error in output as well:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at Camille_fla::MainTimeline/enterF()[Camille_fla.MainTimeline::frame140:130]
Any help is appreciated.

An onEnterFrame listener was called and not removed that was referencing an object (bg) that was not on the stage after the goto call.
function tohallwayClick(event:MouseEvent):void {
**removeEventListener(Event.ENTER_FRAME, enterF);**
gotoAndStop(141);
}

First make sure your button and your code are on the same frame, they can be on different layers, but make sure they are lined up.
If you want it to go to the frame on your main timeline, or stage, instead of writing:
gotoAndStop (141)
try:
stage.gotoAndStop(141);

Related

adobe flash show/hide different movieclips in different frames with one button Error #1009

I created a button to a layer and I am trying to show movieclip com7 in frame 1 when I click the button named quest. Then, I would like to show a different movieclip com9 in frame 2. I put the movieclips in another layer each one in frames1 and 2.
In frame1 the code is:
quest.visible=true;
com7.visible=false;
quest.addEventListener(MouseEvent.CLICK, q7_clicked);
function q7_clicked(event:MouseEvent):void
{
if (com7.visible==false)
{com7.visible=true
}
else
{
com7.visible=false;
}
}
in frame 2:
quest.visible=true;
com9.visible=false;
quest.addEventListener(MouseEvent.CLICK, q9_clicked);
function q9_clicked(event:MouseEvent):void
{
if (com9.visible==false)
{com9.visible=true
}
else
{
com9.visible=false;
}
}
Flash creates the swf without errors but when I click the button in frame2 there is a TypeError:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at meli_fla::MainTimeline/q7_clicked()
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at meli_fla::MainTimeline/q9_clicked()
The issue is that when you add event listeners on the timeline, those listeners do not automatically go away when you change frames (no code does).
So on frame 1, you just have the one listener and it probably works fine.
On frame 2, you create a new listener, but the one from before on frame 1 is also still hanging around, so when you click the quest button, it actually calls q7_clicked and q9_clicked. No matter what frame you are one, at this point clicking the button you added the listeners to will always call both functions.
Your error, is because the objects you're referencing (com9, com7) are likely not around on both frames you are visiting (confirmed from you comments on the question).
To remedy the problem, you need to remove the appropriate event listener when you move to a new frame.
So, wherever in your code you do nextFrame(); or gotoAndStop(2); or however you move the user to another frame, at that time remove the listener on the button:
quest.removeEventListener(MouseEvent.CLICK, q7_clicked);
gotoAndStop(2);
Or, if returning to frame 1:
quest.removeEventListener(MouseEvent.CLICK, q9_clicked);
gotoAndStop(1);

AS3 movie instance turning null

I'm banging my head on what seems like a simple as3 problem. I have a flash chart that contains a series of buttons that go to different parts of the timeline on Roll_over.
so for example - the "Market maneuvers" button looks like this
marketManeuversButton.addEventListener(MouseEvent.ROLL_OVER, marketManeuversButtonReaction)
and the function it calls looks like this
function marketManeuversButtonReaction (event:MouseEvent):void{ gotoAndStop('18'); }
The problem is, when I mouseover that button (and many others), it goes to frame '18' and then throws this error:
Error #1009 Cannot access a property or method of a null object
reference
here is my flash file
Any help would be appreciated. Thanks.
When you change frame, flash recreated all objects in frame, and you loose all your data.
Yes, it's simple AS3 problem, just don't use a scene frames at all. Program all in classes, don't use any frames to code any logic except stop(), gotoAndStop(), gotoAndPlay().
In your problem, put all scene in movieclip, exclude control buttons from it to another movieclip and control scene movie clip with control movieclip >____<. It pegleg. Next time just do it right, don't use scene frames.

how to set actionscript code to execute only once

Okay so I have a movieclip called a_mc, if you click the movieclip, it goes to frame 5, and then on frame 5 there is a button called close_btn where if you click the button, it goes back to frame 1 and it is supposed to make a_mc invisible. Here is the actionscript code for frame 1.
stop();
a_mc.addEventListener(MouseClick.CLICK, aClicked);
function aClicked(event:MouseEvent):void {
gotoAndStop(5);
}
and on frame 5, the actionscript code is
stop();
close_btn.addEventListener(MouseEvent.CLICK, closeCLicked);
function closeClicked(event:MouseEvent):void {
gotoAndStop(1);
a_mc.visible = false;
a_mc.removeEventListener(MouseEvent.CLICK, aClicked);
}
see, the problem is, in frame 5, I make a_mc invisible and remove the event listener and go back to frame 1 and on frame one, it always executes the actionscript code so it again creates the event listener and makes a_mc visible. Any idea on how to stop this from happening?
I tried putting the code from frame 1 into a package and then a class and then a constructer method but it is saying
"Syntax error: package is unexpected"
Could you put all the code that you want to execute once in frame 1? - don't call stop() and let it run to the next frame.
Then put the rest of your code in other key frames and don't use gotoAndStop(1) so frame 1 is only called once?
You can try not removing the event listener on a_mc in frame 5, and then in frame 1 check if the event listener is already present (a_mc.hasEventListener()) as a signal that frame 1 has already been shown. Not exactly a 'bets practices' solution, but it might work.
Unfortunately, depending on the actual conents of those clip, and what happens in other frames, it may be the problem you're having is a consequence of the way movieclip object works in flash. When a frame is changed, flash instantiates new objects on the stage (added in new frame), and removes the ones not needed anymore (depending on the contents, but generally it's true). The 'a_mc' object that you manipulate in frame 5 may not be the same 'a_mc' object that is on the stage when you go back to frame 1. It may have been deleted and reinstantiated in the meantime.
To avoid things like that, it would be a better solution to have controlling code in a class outside of the timeline of the animating clip, or at least to keep the state in a separate object. I work in Flash Builder so I can't help you with the details of such organization in Flash Pro (which I presume you're using), but you could probably have all code on the frame 1 of the main clip, and then put the other movieclips with buttons and stuff as children of the main clip. That way main clip can control the state, and know what to show when.

addEventListener and gotoAndStop for a menu in a game gives error

I'm new at flash as3. Today, I am trying to code a menu in a game which will refer to a startscreen for a game to show the buttons for the game.
In this startscreen, there is a button to link back to the menu. It doesn't work. I am getting this,
Error:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at SuperSpill_fla::MainTimeline/frame1()
It looks like to me the only possible thing that could have happened is that mus doesn't exist anymore. This suggests that the code is running in a frame where mus is no longer on stage.
I would expect that in most versions of the Flash Player that the frame wouldn't fully render between goToAndStop and the next line, but my suggestion would be to either swap the order of those lines or change it to
event.currentTarget.removeEventListener(MouseEvent.CLICK, musSpill)

Play movie clip instance inside of button instance

I placed a movie clip instance inside a button, and I want this movie clip to play when the button is released. I'm using this code on the frame containing the button:
function playMovie(event:MouseEvent)
{
this.theButton.theMC.gotoAndPlay(3);
}
theButton.addEventListener(MouseEvent.MOUSE_UP, playMovie);
When I try to test the flash movie, I get this message:
1119: Access of possibly undefined property theMC through a reference with static type flash.display:SimpleButton.
I can somewhat understand why it doesn't like it, but I do not know how to resolve the issue.
if you are inside of theButton already then you won't need to call "this.theButton" because "theButton" is "this"
try
this.theMC.gotoAndPlay(3);
if you are still unsure of the object parent child relation and you are using the flash IDE, in your actions panel, click the blue target at the top of the actions panel and find the MC you are trying to reference and let the flash IDE figure out the relationships for you.
Give the movieclip in your button an instance name of "theMC". Then use the following code:
function playMovie(e:MouseEvent)
{
this.theButton.getChildByName("theMC").gotoAndPlay(3);
}// end function
theButton.addEventListener(MouseEvent.MOUSE_UP, playMovie);