I have a class that I made to control all my buttons from a centralized location. The buttons are pushed into an array on load and a for loop adds a MouseEvent.CLICK event listener to all the buttons in the array.
Now my problem comes in with the function tied to this event listener. I have created a switch statement
function btnclick(e:MouseEvent):void
{
switch (e.currentTarget)
{
case Profile_btn_63 :
removearrayreference(this);
e.currentTarget.parent.gotoAndStop("profile");
break;
}
}
but the problem is when I test the game it states Profile_btn_63 is undefined. Which is actually true at the very beginning(first frame) as the button hasn't been added to the button array yet nor has an event listener been placed on it. So to get to the point I need help with making flash ignore that Profile_btn_63 is undefined until it eventually does get defined.
Finally this may be somewhat off topic but does anyone know why _63 is added to the end of Profile_btn when it is pushed into my button array?
If you're going to have a "magic switch statement" that does everything in your program - which is a horrible idea in more than one way, but that is a different matter - then you should make the case decisions based on the instance name: switch( e.currentTarget.name )
While a button instance may be null or undefined, a constant String never is.
Related
I'm developing a canvas game that happens to have several scenes. Each scene might end up being a static final frame after having finished. The circumstances are that the ticker and the listener for the "tick" event are still running and keep on rendering full speed - which is asking for cpu usage.
I have tried to remove the listeners at the end of scene and add them back wenn the user interacts and starts the next scene.
I wonder what would be the "createJS" way of doing this.
I see some other options but am a bit lost how to proceed:
Caching the "whole" last frame. Will it make the ticker do "absolutely nothing" performance-wise?
Pause the ticker and check for the paused attribute in the handleTick method: Seems to not take the CPU usage completely down.
Can somebody recommend a way?
On a side note: I need my real "this" object inside the tick function that is bound to the ticker. How can I achieve this? Right now I use this code:
createjs.Ticker.addEventListener("tick", handleTick);
function handleTick(event) {
// Actions carried out each tick (aka frame)
if (!event.paused) {
// Actions carried out when the Ticker is not paused.
}
}
Inside handleTick "this" is not my object that added the listener.
A simple createjs.Ticker.removeEventListener("tick", handleTick); should do just fine as long as handleTick exists in your current scope. See this example.
There are a couple ways to access the scope of the object that assigned the tick listener. For example, you could simply assign this to a local variable like so:
var _this = this;
function handleTick(){
//"_this" now refers to the scope that defined handleTick.
}
Or you can use a delegate. In this example I'm using jQuery's proxy function to scope handleTick to this.
var handleTick = $.proxy(function(){
//"this" refers to the scope that defined handleTick.
}, this);
createjs.Ticker.addEventListener("tick", tickHandler);
I'm working on a Flash project which is separated into separate scenes.
In Scene 1 I have multiple MovieClips (which include event listeners for RESIZE (and others) inside them).
In Scene 2 I have a few common MovieClips and new ones (which also include event listeners for RESIZE (and others) inside them).
After clicking a button from Scene 1 to go to Scene 2, it's fine, except for if I resize the stage and then I get the following error:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
I know it's related to the event listeners, but it would be unrealistic to remove them each individually as it's expected there will be many.
If I undertand your situation correctly, I think you will in the end need to remove each listener individually, or add the resize listener only once. Since you mentioned scenes, am I right to assume you are working on the timeline? I also am assuming the null object reference error comes from a scene that has been removed from the stage, making reference to a display object that is no more, a ref to the stage after the scene has been removed, or just calling a function (the resize handler) on an object that no longer exists.
Some way to deal with this are:
Add some checking in the listener handler functions
if (!this.stage) return
To avoid the errors, but will not help if the object the function is a method of has been removed.
To avoid needing remember to remove hundreds of listeners, create removeAllListeners and addCustomEventListener functions. Instead of the usual addEventListener, call you addCustomEventListener which in turn will call addEventListener. Have addCustomListener store the target, listener function and event string in a dictionary or array of objects. removeAllListeners can loop through the dictionary or array and remove all your listeners. It is a bit like setting up an event hub, but does not go quite that far.
Instead of adding the RESIZE event listener to each scene, add it only once. Then in the listener function call a function on whichever scene is the active scene or view.
This last one is the approach I have seen most often, and is the most bullet proof. It may be tricky to implement on the time line, I have always been a little hazy on timeline variable scope.
Yes, so far as I know there is no good automated way to do this, however it would be a good practice to create a registerAllListeners and a removeAllListeners methods that manually add and remove the appropriate listeners to your object.
I've been debugging the following issue for quite awhile now and have hit a wall.
I've set up a project in Flash (CS4, btw) that has a set of keyframes that I move between to represent the various screens of a game. One of them has a MovieClip defined (with children inside it) representing an option menu, that appears on a couple of different keyframes.
The problem I'm having is that this MovieClip reference seems to be accessible when I first enter the keyframe (using "gotoAndStop"), and occassionally when I move to other frames and back. But in at least one case, when I exit the frame and come back, I get a null reference error (TypeError: Error #1009: Cannot access a property or method of a null object reference). when I try and access it (getChildByName("optionMenuTitle")). I've even tried having the system iterate from 0 to numChildren and print out the name of each object, but it returns NULL at position 7 despite returning numChildren as 9. Does anyone have any idea why this particular MovieClip reference is NULL only in this case??
Here is a basic (abbreviated) rundown of the process occurring:
//set up function to be fired on frame construction
addEventListener(Event.FRAME_CONSTRUCTED, fadeIn, false, 0, true);
public function fadeIn(event:Event):void {
_handler.handle(); //this function is called which runs the debug statement below
trace (mainDoc.numChildren); //displays 9
for (var i = 0; i < mainDoc.numChildren; i++) { trace(mainDoc.getChildAt(i).name); } //throws null when it gets to 7
optionMenuTitle = OptionMenu(mainDoc.getChildByName("optionMenuTitle")); //the original failed call that caused me to debug
}
edit: One other potentially useful bit of information. If I comment out the getChild commands above that error, the frame loads and I can see the MovieClip visually displayed on the stage (although it's not interactive and is constantly cycling through the frames of its child objects). Still can't access it programatically though.
another edit: The object in question is a subclass of MovieClip that I named "OptionMenu". I put a breakpoint in the OptionMenu constructor, and when the frame loads correctly, that breakpoint is hit. When I get the error above, the breakpoint in the constructor is never hit. The debugger doesn't seem to give me access to see what's going on inside Flash's mind when it's instantiating the frame, however, so I can't see the logic as to why the constructor is never called.
Well this one has been driving me crazy. I could not workout why it does not reference your optionMenuTitle when you go back to the frame called title a second time.
The only way I could work around it was to take the 3 buttons out of the OptionMenu MovieClip and put them on the stage with the grey background underneath, essentially doing away with OptionsMenu.
So I moved all initialization code from OptionMenu to your TitleHanlder and also added the destroy calls to your destroy method in TitleHandler for each of the 3 buttons.
I also changed the refs from root to mainDoc:
sound.initialize(LogicGameMain(mainDoc).soundOn);
music.initialize(LogicGameMain(mainDoc).musicOn);
This worked for me as you can still interact with the buttons the second time around. It definately seems like there is some bug with these buttons being nested.
I hope this is useful for you.
I have this in my constructor:
addEventListener(Event.REMOVED_FROM_STAGE, actualDestroy);
And this in actualDestroy:
public function actualDestroy(e:* = null){
removeEventListener(Event.REMOVED_FROM_STAGE,actualDestroy);
if(this.parent){
this.parent.removeChild(this);
}
}
The problem is I get Error: Error #2094: Event dispatch recursion overflow. Why does removechild keep getting called if this.parent does not exist? Why doesn't removing event listeners work?
The name of the event is misleading. removedFromStage, according to the docs, is "dispatched when a display object is about to be removed from the display list". In other words, this is what's happening in your code:
Somewhere in your code, you call parent.removeChild(this)
actualDestroy is immediately called. At this point, the object is still in the display list, so this.parent != null
In actualDestroy, you call parent.removeChild(this) again.
Go to step 2
So to fix the issue, you might want to refactor your code (an object removing itself from the display list is never a good idea anyway), or perhaps use some boolean like beingRemoved to check whether the object is being removed from the list already. In which case, don't call parent.removeChild(this) in actualDestroy.
I have a function that states when movieclip1 is dragged and hits a line then it stops the drag, however it seems to stop the entire drag function in the swf on the other movieclips even though they arent called in the function. Can somebody please help me with this.
Regards
T
Here is the code:
function hitTest(event:Event):void
{
if (movieclip1.hitTestObject(line))
{
movieclip1.stopDrag();
}
else
{
}
}
Are you absolutely positive you only have one instance of movieclip1 on your stage? Definitely double check. Are you creating them dynamically, or are they preloaded when your SWF loads?
If they're preloaded:
Perhaps during testing you made some quick copies of it, and now those copies have the same name and they're all responding the same. That's my first guess.
If they're loaded dynamically:
Check the function where they're being created. If you're naming them in a loop (with a number on the end like the above), be sure that you're properly increasing the numeric value used on the end.