AS3 Vector remove display list - actionscript-3

I have an app which is using a vector object to create and display multiple dynamic items on the stage.
When I quit the game and then return to the inGame screen the objects are still visible. I have tried a number of ways to remove but nothing has worked.
I have null'ed the vectors but the objects still remain on the stage.
Basically I just need to clear the stage when the game is quit.
I am using:
var item = new Vector.<Item>();
to create.
The user quits the game by hitting the pause button and then a 'back to menu' button.
Any guidance is appreciated.

Once you perform an addChild() on something, that something receives another link to it, namely from display list. So you have to manually call removeChild() on each of your dynamic objects you store in your Vector, before actually dropping the vector.
var item:Vector.<Item>;
for (var i:int=item.length-1;i>=0;i--)
item[i].parent.removeChild(item[i]);
item=null;

If all of your DisplayObject's are in the item Vector and Item is an ancestor of DisplayObject then following loop executed when you are going to the main screen will remove them from it's container.
var child:Item;
while(item.length)
{
child = item.shift();
if(child)
{
//perform some cleaning functionality e.g. child.destroy();//if there is destroy method for disposing Item class
//
if(child.parent)
{
child.parent.removeChild(child);
}
child = null;
}
}
//
item = null;

Related

How do you share a variable between scripts using the MovieClip variable?

I'm currently trying to code an interactive timeline for my Uni project (keep in mind im a new coder) and we go over basic actionscript stuff. I was taught to communicate between scripts using a movieclip variable and declaring this.parent.
I have 3 scripts, one that controls the button that is used to move forward in the timeline, one is main, and the other controls the text box which displays the timeline. I placed a number variable in main, initialised at 0(timeCount). In the button script, i have it linked to main using refToMain, my movieclip variable. Within the button script, if the user clicks on the button, it rises the number variable from main using refToMain(refToMain.timeCount). It was my ambition to have the text box script track the number and each number has a different bit of the timeline on. However, when I trace timeCount in the button script, the number seems fine and raises accordingly, however it doesnt change the number in any other script. How can I fix this using basic as3 code?
In Main:
var timeCount:Number = 0;
In Button:
public function mDown (mDown:MouseEvent){
refToMain.timeCount += 1;
if(refToMain.timeCount >= 10){
refToMain.timeCount = 10;
}
trace(refToMain.timeCount);
In timeline:
if(refToMain.timeCount == 0){
timelineText.text = "welcome"
}
if(refToMain.timeCount == 1){
timelineText.text = "hello"
}
Are you expecting the code in your timeline to run continuously instead of just once? A frame script will only run once each time the timeline reaches that frame. And if you only have one frame, the timeline won't advance at all. If that's the case, a simple fix would be to add another frame to your timeline with F5, and then your timeline will alternate between your two frames forever so that your script on frame 1 will execute every other frame.
A better option would be to call the script that updates the timeline text directly every time the button is clicked. So you would move the code from your timeline script to your button script like this:
public function mDown (mDown:MouseEvent) {
refToMain.timeCount += 1;
if(refToMain.timeCount >= 10) {
refToMain.timeCount = 10;
}
trace(refToMain.timeCount);
if(refToMain.timeCount == 0) {
MovieClip(root).timelineText.text = "welcome";
}
if(refToMain.timeCount == 1) {
MovieClip(root).timelineText.text = "hello";
}
}
There are several ways and approaches to access objects and variables across your application.
1) Traversing. The (probably) older and the most straightforward one is fully understanding and controlling the display list tree. If you understand where your current script is and where your target script is, you just traverse this tree with root to go straight to the top, parent to go level up and getChildByName or [] or dot notation to go level down.
Pros: it's simple. Contras: The weak point of this approach is its inflexibility. Once you change the structure of display list tree, the access would presumably be broken. Also, this way you might not be able to access things that are not on the display list. Also, there are cases the dot notation would not work, and there are cases getChildByName would not work. Not that simple, after all.
2) Bubbling events. These are events that bubble from the depths of display list to the root. Mouse events are bubbling: you can catch it anywhere from the deepest object that had some mouse event then all its parents right up to the stage. You can read about them here. So, you can send bubbles from whatever depth you want then intercept them at the any parent of the event target:
// *** TextEvent.as class file *** //
package
{
import flash.events.Event;
public class TextEvent extends Event
{
static public const TEXT_EVENT:String = "text_event";
public var text:String;
// Although it is not a very good practice to leave the basic Event
// parameters out of it, but it will do for this example.
public function TextEvent(value:String)
{
// Set type = "text_event" and bubbles = true.
super(TEXT_EVENT, true);
text = value;
}
}
}
// *** Button script *** //
import TextEvent;
// Dispatch the event.
dispatchEvent(new TextEvent("welcome"));
// *** Main timeline *** //
import TextEvent;
// Subscribe to catch events.
addEventListener(TextEvent.TEXT_EVENT, onText);
function onText(e:TextEvent):void
{
// Extract the passed text value.
timelineText.text = e.text;
}
Pros: it is good in an app architecture terms. Contras: you cannot catch the bubbling event at the point that is not parent of event source.
3) Static class members. Or singleton pattern, its basically the same. You can devise a class that shares certain values and references over the whole application:
// *** SharedData.as class file *** //
package
{
import flash.display.MovieClip;
public class SharedData
{
static public var MainTimeline:MovieClip;
}
}
// *** Main timeline *** //
import SharedData;
// Make root accessible from anywhere.
SharedData.MainTimeline = this;
// *** Button script *** //
import SharedData;
// You can access main timeline via shared reference.
SharedData.MainTimeline.timelineText.text = "welcome";
Pros: you are not limited by display list structure any more, you can also share non-visual instances this way, anything. Contras: careful with timelines, they tend to destroy and create timeline instances as playhead moves, so it is not impossible to end up with a reference to a removed object while timeline holds a new instance that is no longer shared.

Can i create a function to tell a button to open a movie clip of the same name

I am new to the actionscript side of flash,
I am working on a map that has say 20 popups(movieclips) and the countries are the buttons, i have just been informed i need to add 60 more.
Below is an example of the code i have been using
english_movie.visible=french_movie.visible=turkish_movie.visible=false
english_btn.addEventListener(MouseEvent.CLICK, englishButtonClick);
french_btn.addEventListener(MouseEvent.CLICK, frenchButtonClick);
turkish_btn.addEventListener(MouseEvent.CLICK, turkishButtonClick)
function englishButtonClick(event:MouseEvent):void {
english_movie.visible=true;
english_movie.play();
french_movie.visible=turkish_movie.visible=false
}
function frenchButtonClick(event:MouseEvent):void {
french_movie.visible=true;
french_movie.play();
english_movie.visible=turkish_movie.visible=false
}
function turkishButtonClick(event:MouseEvent):void {
turkish_movie.visible=true;
turkish_movie.play();
english_movie.visible=french_movie.visible=false
}
Im thinking there must be an easier way to do this than replicating the code over and over.
Any help would be much appreciated.
Here's how to simplify the whole thing with code: Each btn object is
related to one movie object. This can be achieved with a Dictionary.
var btnToMovieAssociation:Dictionary = new Dictionary();
btnToMovieAssociation[english_btn] = english_movie; // repeat this line for every btn/movie pair
Now you have to generalise your click handler. The key difference
between each function (apart from making one certain movie visible)
is that they all make certain other movies invisible. But actually,
it's sufficient to only make the previously visible movie invisble.
To do this, create a variable that keeps track of the current visible
movie.
var currentMovie:MovieClip = english_movie;
Initialising the variable with english_movie has no effect on the
program. you can pick any other of the movies. It will make things
easier in the following code if this variable is initialised.
Now your function does effectively this:
make movie of clicked button visible
play this movie
make last movie invisible
Here's the cool part. You only add one listener. Look up if something
is in the dictionary for the clicked thing and consider that the
movie you want to show next.
addEventListener(MouseEvent.CLICK, buttonClick);
function buttonClick(event:MouseEvent):void
{
var movie:MovieClip = btnToMovieAssociation[event.target]
if (movie == null)
return; // nothing in the dictionary, it wasn't a button that was clicked.
movie.visible=true;
movie.play();
currentMovie.visible = false;
currentMovie = movie;
}
There are problems with this solution:
You still have to declare every pair, which is still tedious and prone to erro. (you have to type every name twice)
If your buttons are made up of several objects, event.target might point to them instead of the button as a whole. But with only
the btns in the dictionary and not all their individual parts,
nothing would be found in the dictionary. This can be circumvented by
setting mouseChildren = false; on every btn.
i posted this question else where and got this response
var tl:MovieClip=this;
var mc:MovieClip;
var i:int;
var buttonA:Array=[english_btn,french_btn,turkish_btn];
for(i=0;i<buttonA.length;i++){
buttonA[i].addEventListener(MouseEvent.CLICK,buttonF);
tl[buttonA[i].name.split("_")[0]+"_movie"].visible = false;
}
function buttonF(e:MouseEvent):void{
for(i=0;i<buttonA.length;i++){
tl[buttonA[i].name.split("_")[0]+"_movie"].visible = false;
}
tl[e.currentTarget.name.split("_")[0]+"_movie"].visible=true;
}
Which works great.

Turn image array images to buttons AS3

I'm creating an app with a search function. I display the images by loading from the array the one's which match the search criteria. All the images are loaded from the library. I want to be able to click on an image as though it were a button. Once I click I want to goto frame 3 and change a variable integer to say which image was clicked on so that I can display the information about the photo in frame 3. Can I do this using an event listener say
imagesArray[i].addEventListener(MouseEvent.CLICK, imageClick);
function imageClick(event:MouseEvent):void
{
gotoAndStop(3);
current = i;
}
or similar,
Thanks
Yes, but it won't be as easy. First, Bitmaps do not process events, so you can't assign a listener directly to a Bitmap object. Next, there is no "i" available in such a construction, you have to determine that "i" by yourself. To do that, you parse event.target property, which is the object that's been clicked. You wrap each Bitmap object into a separate Sprite object, assign listeners to these sprites, then you parse event.target to get the relevant object reference out of it, grab the index via indexOf() call, and assign it to global current variable.
for (i=0;i<imageArray.length;i++) {
var sp:Sprite=new Sprite();
sp.addChild(imageArray[i]);
// position "sp" correctly here
addChild(sp);
sp.addEventListener(MouseEvent.CLICK, imageClick);
}
function imageClick(e:Event):void {
var content=e.target.getChildAt(0); // the object that was wrapped
var i:int=imageArray.indexOf(content);
if (i==-1) return; // OW, out of array
current=i;
gotoAndStop(3);
}
I'm not so sure that setting "current" to "i" would work as the function wouldn't be running at the same time as the for loop.
I'm assuming that because you're using the [i] that you've added the event listeners in a for loop?
What you could do is:
for (var i:int = 0; i < (howeverManyTimesToRun); i++)
{
imagesArray[i].addEventListener(MouseEvent.CLICK, imageClick);
imagesArray[i].myIndex = i;
}
And then in your function (outside of the for loop)
function imageClick (e:MouseEvent) {
gotoAndStop(3);
current = e.currentTarget.myIndex;
}
Also in your for loop you might want to add
imagesArray[i].buttonMode = true;
To change the mouse cursor to a hand when their mouse goes over your image.

I can't seem to access automatically named objects (instance##) placed on the stage in AS3, am I missing something?

I have a movieclip in the library that is added to the stage dynamically in the document class's actionscript. This movieclip contains many many child images that were imported directly from photoshop at their original positions (which must be preserved).
I do not want to manually name every single image instance, as there are dozens upon dozens.
I have already gone through and manually converted the images to symbols, as apparently flash won't recognize the "bitmap" objects as children of a parent movieclip in AS3 (numChildren doesn't see the bitmaps, but it sees the symbols).
I have an array filled with references to the dozens of children, and I loop through it, checking if each one is under the mouse when clicked. However, somehow, it is not detecting when I click over the items unless I manually name the child symbols (I tested by manually naming a few of them -- those ones became click-sensitive.)
I have already done trace() debugging all throughout the code, verifying that my array is full of data, that the data is, in fact, the names of the instances (automatically named, IE instance45, instance46, instance47, etc.), verifying that the function is running on click, verifying that the code works properly if I manually name the symbols.
Can any one see what's going wrong, or what aspect of flash I am failing to understand?
Here is the code:
//check each animal to see if it was clicked on
private function check_animal_hits():void
{
var i:int = 0;
var animal:Object = this.animal_container;
for (i=0; i<animal.mussels.length; i++)
{
if (this.instance_under_cursor(animal.mussels[i].name))
{
var animal_data = new Object();
animal_data.animal = "mussel";
this.send_data(animal_data);
}
}
}
Here is the code for the instance_under_cursor() method:
// Used for finding out if a certain instance is underneath the cursor the instance name is a string
private function instance_under_cursor(instance_name)
{
var i:Number;
var pt:Point = new Point(mouseX,mouseY);
var objects:Array = stage.getObjectsUnderPoint(pt);
var buttons:Array = new Array ;
var o:DisplayObject;
var myMovieClip:MovieClip;
// add items under mouseclick to an array
for (i = 0; i < objects.length; i++)
{
o = objects[i];
while (! o.parent is MovieClip)
{
o = o.parent;
}
myMovieClip = o.parent as MovieClip;
buttons.push(myMovieClip.name);
}
if (buttons.indexOf(instance_name) >= 0)
{
return true;
}
return false;
}
Update:
I believe I have narrowed it down to a problem with getObjectsUnderPoint() not detecting the objects unless they are named manually.
That is the most bizarre way to find objects under mouse pointer... There is a built-in function that does exactly that. But, that aside, you shouldn't probably rely on instance names as they are irrelevant / can be changed / kept solely for historical reasons. The code that makes use of this property is a subject to refactoring.
However, what you have observed might be this: when you put images on the scene in Flash CS, Flash will try to optimize it by reducing them all to a shape with a bitmap fill. Once you convert them to symbols, it won't be able to do it (as it assumes you want to use them later), but it will create Bitmpas instead - Bitmap is not an interactive object - i.e. it doesn't register mouse events - no point in adding it into what's returned from getObjectsUnderPoint(). Obviously, what you want to do, is to make them something interactive - like Sprite for example. Thus, your testing for parent being a MovieClip misses the point - as the parent needs not be MovieClip (could be Sprite or SimpleButton or Loader).
But, if you could explain what did you need the instance_under_cursor function for, there may be a better way to do what it was meant to do.

Timeline instances not on first frame

It's been a while since I've had to write Actionscript that really needs to integrate with the timeline (in this case, controlling a series of frames that must happen in a certain sequence) and I am trying to figure out what to do.
In the first few frames, I have a button "next_1".
At frame 10, I need to have another button "next_2". I really really need this button to not be on frame one (I could possibly just make it invisible, but that's going to create a clickable area that I don't want).
The problem is, anything I don't put on "frame_1" renders as null in my Document class.
Is there any solution to this? I would rather not have to write my script on the timeline if possible (it seems easier in the long run to keep it in a document class)...
Items on the timeline are created on the fly, so if the playhead has not reached frame 10, next_2 is not created.
Easiest Document-class solution:
Create an array of frame labels like ["label1", "label2"]
Create sectionIndex var and set it to 0
Create a next button on its own layer so it is always showing.
When the next button is clicked, increment sectionIndex, then gotoAndPlay(myLabels[sectionIndex])
Okay, directly lifted from "Real World Flash Game Development":
/**************************************************
* FRAME LABELS *
**************************************************/
private function enumerateFrameLabels():void {
for each (var label:FrameLabel in currentLabels) {
addFrameScript(label.frame-1, dispatchFrameEvent);
}
}
private function dispatchFrameEvent():void {
dispatchEvent(new Event(currentLabel, true));
}
This dispatches an event at each frame label on the timeline.
Then you can just add event listeners for each frame:
addEventListener("name_of_my_framelabel", frameHandler);
addEventListener("another_framelabel", frameHandler);
And write a switch statement to add event listeners for the buttons when they actually show up on the timeline.
private function frameHandler(e:Event):void {
switch(e.type) {
case 'screen_2':
stop();
next_2.addEventListener(MouseEvent.CLICK, click2, false, 0, true)
break;
}
}