without getting too verbose....i have been learning AS3 over the last week by building a small Flash site. the navigation menu is constructed as a custom class rather than on a keyframe in the flash file itself. I now find myself simply needing to issue a command to control the main flash file's timeline in this manner...
pages.gotoAndPlay(framelabel);
from the custom class.
help.
The problem here you have is with scope.
There are two ways to do this in a simple way.
You can path to the timeline that you require to change using the parent property e.g. this.parent.parent.parent.gotoAndStop(...)
or just use the root value if the timeline you're trying to change is on the root
root.gotoAndStop(...)
or
stage.gotoAndStop(...)
Related
I'm attempting to set up a saving and loading system for a flash game I am creating. At the moment I decided to attempt to get the Save File Selection part of my new game menu to work before I proceeded any further with it. I drew up the 'DifficultySelect' screen (which contains save file selection as well as a few other things) in flash, then converted it into a symbol. I made 10 save file symbols inside of this, and created base actionscript files for them. The entire 'DifficultySelect' becomes a child of my 'Main.as' once you proceed through the title screen. I am trying to have my save file data inside of my Main.as, such as levels, health, progress, etc, as well as which save file is currently in use. However, I am unable to create a way for my Main.as to access a MouseClick function for the save file, as I can't simply have a Savefile0.MouseEvent.CLICK event in my Main.as file, as I am not creating a variable to add it to the stage.
I suppose the tl;dr question version of my situation is: How can I get my Main.as to activate one of its functions when SaveFile0 has been clicked? Also, how do I refer to a child from a parent class?
You ask how to refer to a child from parent, but since the child usually "knows" its parent, I suggest following solution:
Your child (SaveFile) should listen for the event (MouseEvent). Once the event is dispatched, you have two options. Either you can dispatch a custom event on parent or directly invoke a public function of the parent.
This is assuming your SaveFile is a MovieClip added to Main:
Inside SaveFile:
var _parentMC:MovieClip = this.parent as MovieClip;
_parentMC.functionToCall();
The best practice, however is to dispatch a custom event in SaveFile, and listen for it in main:
Inside SaveFile:
var customEvent:Event = new Event("customEvent");
this.dispatchEvent(customEvent);
Inside Main:
saveFile.addEventListener("customEvent",functionToCall();
functionToCall(e:Event):void{
}
So I've been following this tutorial on AS3 and Flash. Its been going well until, note I have tried to contact the writer of the tutorial and had no reply. Here's what it tells me to do;
Right-click PlayScreen in the library, select Properties, and check Export for ActionScript. This time, instead of accepting the default value, enter the name of your document class. Click OK.
So it pops up an error, first we’ll have to make a new document class, since no two different objects can share the same class. Cancel the Properties box.
Hit File > New and select ActionScript File. Enter the (by now familiar) code.
Save this in the Classes directory as DocumentClass.as. (There’ll be no confusing the purpose of this file!) Now, back in your FLA, change the document class to DocumentClass.
Check everything’s fine by clicking that pencil icon — if it’s all OK, that should bring up the AS file that you just created.
// So this bits all fine, its the next that i'm stuck with:
Now you can set the PlayScreen‘s class to AvoiderGame. So do so!
// So I go ahead into the properties and change the name but then it pops up with the same error as before: 'Please enter a unique class name that is not associated with other library symbols'
What does this mean!? How do I resolve this!?
Full tutorial here:Flash Tutorial
Its hard to tell what you are trying to accomplish without knowing what all the parts you are referring to actually do, which are objects in the library and which are classes, but maybe this can help:
First of all, document class in AS3 typically refers to the project's main set of code that initializes the app. This class can be called anything but is often called Main, and is entered in the property panel that is displayed when you click the projects main stage in the field called class.
Now, when linking a class to an object in the library, its a little different. In the library object's property panel, tick the box for Export for Actionscript, and put a unique name in the top box. This is what you reference in your code to call it, like new somethingOrOther() or using the pic below as an exaample, new Ball(). The second box is the base class, pathed to where it lives in your code base. This is the class you will write that actually controls the object you've linked the class to. Giving a linked object a base class and a unique identifier allows you to use the same base class for multiple linked objects.
Note that when you do this approach, Flash will warn you that there is no class associated with Ball and one will be created for you. Don't worry, this is normal behavior. If you set this up properly, your object will still be controlled by its base class.
I need to create a single SWF with no external files, so I'm trying to add an internal preloader to my Flash project which has [embed] assets. I know [embed] causes problems with preloaders because it puts the assets on frame 1. I have tried the solutions recommended in these posts, where you set the document class to your preloader class:
Preloader for SWF with embed bytearray
How to create Preloader in AS3
I can get it to work, but ONLY if I comment out any lines of code that involve the stage, otherwise I get an "Error #1009: Cannot access a property or method of a null object reference." Those lines are essential though, so does anyone know how to fix those errors with the stage?
You haven't posted your code or your fla, so all I can do is share what works for me.
First, I wouldn't use Embed. Instead, use a swc. I have found that Embed can be unreliable as far as actually getting the entire asset in there (at least when publishing with Flash Builder + Flash Pro, which is my workflow).
Once you have your assets in a swc, try the following steps:
Set your export frame to Frame 10 (or any frame other than 1--I like frame 10 because then you can read the label that says "Preloader")
Put your actual content on frame 11. You can structure this a lot of ways. Since I program to Interfaces, I give whatever is on frame 11 an instance name and then use a setter to determine that my "first thing" has been placed on stage. I can get away with this because my main Document Class just knows the definition of the Interface, not the full implementation of the Class, so the Class does not need to load for the main Document Class to work. You probably aren't truly using the timeline and probably didn't program to interfaces, so you'll probably just set the base class of the symbol that's on frame 11 to the main logic of whatever you're trying to do.
Put your preloader graphics in Frame 1. I'm not sure why your stage references are so important. I, personally, don't use any logic in the preloader. Instead, I use a spinner that spans frames 1-10 (plus the word "Loading...". The spinner just spins while the classes load. The embed frame acts as a temporary "stop" that just holds the timeline back until those classes have been loaded. Once the classes have been loaded, the timeline will act like you called play() on it. So it really can be that simple. If you need it to be more complicated, give one of your preloader graphics an instance name and set up a getter/setter pair for it, then use the setter to trigger your logic that accesses the stage. You are pretty much guaranteed to have a valid stage at that point.
Word of warning: if you did make use of the timelime, you will get strange results if you try to jump to a frame that isn't loaded yet, so make sure to check to see if a given frame is loaded if it's near the end of your main timeline and your main timeline is heavy with assets before calling goToAndPlay() or goToAndStop().
Some references that might help you further:
Preloaders vs as 3 (I'd recommend you read the entire series this is part of. This is an amazing series I wish I'd found 3 years ago)
Solving the Frame 2 Problem Presentation and code
Combining the Timeline with OOP The example code for that is here (long story)
I'm new to coding and AS3. I was reading about adding things to the stage using AS3 and learned about the addChild method. Reading more I found that there are different ways to use it. I also read that some ways are better than others, and that some ways are not good at all and better avoided.
I don't trust those sources though. As a coding newbie I come asking for help, StackOverflow. I'm about to start an addChild heavy project and I want to start it with the right implementations. I trust you, so let me ask you this: What's the correct use of addChild?
I just want to add things to the stage, but I read that it's not good to add them directly to the stage (without further argument though).
stage.addChild()
this.addChild()
addChild()
Are there other ways? Which one should I use?
Thanks for your time. :)
As the top-level container for all display objects in the display list hierarchy, there is only one Stage no matter how many SWF files are loaded into the runtime. So, generally, objects should not be added to the Stage, directly, at all. The only object the Stage should contain is the root object.
Generally, you should not use: stage.addChild()
Adding a DisplayObject to the display list should be performed within the scope of a DisplayObjectContainer.
Each SWF file has an associated ActionScript class, known as the main class of the SWF file which extends a display object. From this class or any child within the hierarchy you may call addChild().
The following are equal, and would add a child within the scope of the current display object container.
this.addChild()
addChild()
The this keyword explicity defines scope; however, is generally implicit when left off.
While a display object added via addChild() is added to the front (top) of all other children, to add a child to a specific index position, use the addChildAt() method.
References:
Display Programming
Basics of display programming
Adding display objects to the display list
I develop a project in FlashBuilder. The graphics and UI elements i create in the Flash IDE and give them Export Classnames. then I put the SWC in the library paths of the FlashBuilder project and create the UI elements by instanciation.
Now I want to add a Preloader for the application. I follow this article, which works:
http://pixelpaton.com/?p=4642
My question is now: I also need some graphics for the preloader. But how do I ensure that the graphics for the preloader will be loaded first, such that the preloader class can start as soon as possible?
The compiler will figure out the dependencies for your preloader class, and load them first.
For example:
public function Preloader()
{
addChild(new UIElementFromFlash());
}
Flash Builder will know UIElementFromFlash needs to be loaded before Preloader. It will also load Preloader before your main class and its dependencies as long as you have the Frame metadata tag from the article.
I'd suggest to make 2 swf files if it's possible. Make a loader.swf which loads your application swf and displays the progress and your loading animation/graphics.
See an example here: http://www.republicofcode.com/tutorials/flash/as3preloader/
Then you'll have to add URLLoader class and load your application.swf.
Try looking here: http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/URLLoader.html
Like Gio suggested, having two SWF files is the best practice.
However, one other solution is to use the -frame two argument of the Flex compiler. All your definitions (code and assets) will be added to the second frame of the movie, allowing your main class to listen for the loading progress of the application and display animations.
Be careful to not reference anything from the main application in your first frame, to prevent adding more weight to it.
More detail on this technique here:
http://www.andymoore.ca/2009/08/flexsdk-3-3-how-to-make-a-flash-preloader-in-as3/