I'm getting my feet wet with AS3, Flixel and component/entity systems (yes, all at the same time), and my entities (which subclass FlxSprite) aren't being added correctly (i.e., not at all). I've just spent a good two hours nailing down the offending line. If I remove it, the rest of the game chugs along happily.
What's wrong with this code?
public function addComponent(c:Component):void
{
var type:String = Object(c).constructor.toString();
FlxG.log("type=" + type);
this._components[type] = c; // The evil line
FlxG.log("now type=" + _components[type]);
c.setData(this);
}
components is an Object field being used as a map/dictionary. type gets set to [class PlayerComponent]. Based on googling, this is valid and should work as intended.
Based on the output from the console, it's just bailing after that line--not crashing entirely. What's going on? More details gladly offered upon request.
I'm not certain about Component - not my forte - but I do know that FlxGroup and its children (which include FlxState) have a method called add() which adds children to them.
So if you have an FlxSprite, the correct way (in flixel) to add it to the chain of things to update/draw is to use that; you can add it directly to your state or to a group that is a child of the state.
Function docs: http://flixel.org/docs/org/flixel/FlxGroup.html#add()
Related
I'm surprised I don't know how to do this, but as it turns out I really don't; simply put, I'm trying to make a side-scrolling shooter game, a basic one and in it, I have 50 stars spawned on-screen through a "for" loop upon the game starting. There is a function which does this and a listener is at the beginning. Problem is, when you lose the game and go back to main menu, 50 more stars would be spawned, which isn't what I want. So, I'm trying to make an "if" statement check at the beginning, so that the game checks whether there is an instance/movie clip of the star object/symbol before determining whether the function that spawns stars should be called out with a listener. So, how do I do this? I looked through some other checks and they didn't help as the codes presented were vastly different there and so I'm just getting errors.
Let me know if a better explanation is needed or if you would like to see some of the code. Note that the game overall already has a lot of code, so just giving all of it would probably not be helpful.
I suggest you rethink your approach. You're focusing on whether stars have been instantiated. That's ok but not the most basic way to think about it.
I would do this instead
private function setup():void{
loadLevel(1);
addListeners();
loadMusic();
// etc...
// call all functions that are needed to just get the app up and running
}
private function loadLevel(lev:int):void{
addStars();
// call all functions that are needed each time a new level is loaded
}
private function restartLevel():void{
// logic for restarting level,
// but this *won't* include adding star
// because they are already added
}
There are other ways to do this but this makes more sense to me than your approach. I always break my game functions into smaller bits of logic so they can be reused more easily. Your main workhorse functions should (IMHO) primarily (if not exclusively) just call other functions. Then those functions do the work. By doing it this way, you can make a function like resetLevel by assembling all the smaller functions that apply, while excluding the part about adding stars.
Here's what I did to solve my problem... Here's what I had before:
function startGame():void
{
starsSpawn();
//other code here
}
This is what I changed it to:
starsSpawn();
function startGame():void
{
//other code here
}
when you said existance, so there is a container, i named this container, (which contain stars , and stars was added to it) as starsRoot, which absolutely is a DisplayObject (right?)
now, to checking whole childrens of a DisplayObject, we have to do this :
for (var i:int=0; i<starsRoot.numChildren; i++) {
var child = starsRoot.getChildAt[i];
}
then, how to check if that child is really star!?
as you said
whether there is an instance/movie clip of the star
so your stars's type is MovieClip, and they don't have any identifier (name), so how to find them and make them clear from other existing movieclips. my suggestion :
define a Linkage name for stars from library, thats a Class name and should be started with a capital letter, for example Stars
now, back to the code, this time we can check if child is an instance of Stars
for (var i:int=0; i<starsRoot.numChildren; i++) {
var child = starsRoot.getChildAt[i];
if (child is Stars) {
// test passed, star exist
break;
}
}
There are many examples of doing this in axml, but I would like to have a complete binding using code behind. To be honest, I would like to have NO axml, but seems like creating all the controls programmatically is a nightmare.
I first tried the suggestions at:
MvxListView create binding for template layout from code
I have my list binding from code-behind, and I get six rows (so source binding is working); but the cells itself does not bind.
Then at the following url:
Odd issue with MvvmCross, MvxListViewItem on Android
Stuart has the following comment: Have looked through. In this case, I don't think you want to use DelayBind. DelayBind is used to delay the binding action until next time the DataContext is set. In Android's MvxAdapter/MvxListItemView case, the DataContext is passed in the ctor - so DataContext isn't set again until the cell is reused. (This is different to iOS MvxTableDataSource).
So in essence, the only example I see shows DelayBind, which shouldn't work.
Can someone please show me some examples... thanks in advance.
Added reply to Comments:
Cheesebaron, first of all, a huge thank you and respect for all your contributions;
Now, why not use axml? Well, as programmers, we all have our own preferences and way of doing stuff - I guess I am old school where we didn't have any gui designer (not really true).
Real reasons:
Common Style: I have a setup where Core has all the style details, including what all the colors would be. My idea is, each platform would get the style details from core and update accordingly. It's easy for me to create controls with the correct style this way.
Copy-Paste across platform (which then I can even have as linked files if I wanted). For example, I have a login screen with web-like verification, where a red error text appears under a control; overall on that screen I have around 10 items that needs binding. I have already got iOS version working - so starting on Droid, I copied the whole binding section from ios, and it worked perfectly. So, the whole binding, I can make it same across all platform... Any possible error in my way will stop at building, which I think is a major advantage over axml binding. Even the control creation is extremely similar, where I have helpers with same method name.
Ofcourse I understand all the additional layout that has to be handled; to be honest, it's not that bad if one really think it through; I have created a StackPanel for Droid which is based on WP - that internally handles all the layouts for child views; so for LinearLayout, all I do is setup some custom parameters, and let my panel deal with it. Relative is a different story; so far, I have only one screen that's relative, and I can even make it Linear to reduce my additional layout code.
So, from my humble point of view, for my style, code-behind creation allows me to completely copy all my bindings (I do have some custom binding factories to allow that), copy all my control create lines; then only adding those controls to the view is the only part that is different (then again, droid and WP are almost identical). So there is no way I can miss something on one platform and all are forced to be the same. It also allows me to change all the styles for every platform just by changing the core. Finally, any binding error is detected during compile - and I love that.
My original question wasn't about NOT using axml... it was on how to use MvxListView where all the binding is done in code-behind; as I have explained, I got the list binding, but not the item/cell binding working.
Thanks again in advance.
Here is part of my LoginScreen from droid; I think it's acceptable amount of code for being without axml file.
//======================================================================================================
// create and add all controls
//======================================================================================================
var usernameEntry = ControlHelper.GetUITextFieldCustom(this, "Username.", maxLength: 20);
var usernameError = AddErrorLabel<UserAuthorization, string>(vm => ViewModel.Authorization.Username);
var passwordEntry = ControlHelper.GetUITextFieldCustom(this, "Password.", maxLength: 40, secureTextEntry: true);
var passwordError = AddErrorLabel<UserAuthorization, string>(vm => ViewModel.Authorization.Password);
var loginButton = ControlHelper.GetUIButtonMain(this);
var rememberMe = new UISwitch(this);
var joinLink = ControlHelper.GetUIButtonHyperLink(this, textAlignment: UITextAlignment.Center);
var copyRightText = ControlHelper.GetUILabel(this, textAlignment: UITextAlignment.Center);
var copyRightSite = ControlHelper.GetUIButtonHyperLink(this, textAlignment: UITextAlignment.Center);
var layout = new StackPanel(this, Orientation.Vertical)
{
Spacing = 15,
SubViews = new View[]
{
ControlHelper.GetUIImageView(this, Resource.Drawable.logo),
usernameEntry,
usernameError,
passwordEntry,
passwordError,
loginButton,
rememberMe,
joinLink,
ControlHelper.GetSpacer(this, ViewGroup.LayoutParams.MatchParent, weight: 2),
copyRightText,
copyRightSite
}
};
I just came across a similar situation myself using Mvx4.
The first link you mentioned had it almost correct AND when you combine it from Staurts comment in the second link and just remove the surrounding DelayBind call, everything should work out ok -
public class CustomListItemView
: MvxListItemView
{
public MvxListItemView(Context context,
IMvxLayoutInflater layoutInflater,
object dataContext,
int templateId)
: base(context, layoutInflater, dataContext, templateId)
{
var control = this.FindViewById<TextView>(Resource.Id.list_complex_title);
var set = this.CreateBindingSet<CustomListViewItem, YourThing>();
set.Bind(control).To(vm => vm.Title);
set.Apply();
}
}
p.s. I have asked for an Edit to the original link to help others.
I want to try a simple task where if i move a object inside the world and then press a button it should go back to its original position , but its not working , below is the code i am using - the file is here - http://www.fastswf.com/yAnIvBs (when i remove the event listener)
with event listener - http://www.fastswf.com/rpYsIt8
////////========================
stop();
var startXPos:Number = level1WorldObj.box1.x;
var startYPos:Number = level1WorldObj.box1.y;
function areaS(e:Event) {
level1WorldObj.box1.y= startYPos;
level1WorldObj.box1.x= startXPos;
level1WorldObj.box1.removeEventListener(Event.ENTER_FRAME, areaS);
}
but1.addEventListener(MouseEvent.CLICK,nClick3);
function nClick3(event:MouseEvent):void{
level1WorldObj.box1.addEventListener(Event.ENTER_FRAME, areaS);
level1WorldObj.box1.y= startYPos;
level1WorldObj.box1.x= startXPos;
}
/////////////////======================
Now i want to be able to do it many time so i kept the variables that detect the initial x, y as global ...
Here you can see how it behaves in debugdraw mode , strangely only the clip moves not the actual body - http://www.fastswf.com/-Ijkta4
Can some one please guide me here ...
Thanks in advance ...
Jin
The graphics that you see (box1) aren't related to the physical object behind the scenes - you're currently only moving the graphics not the object itself.
You need to use either SetPosition() or SetTransform() on the b2Body of the object
Edit 07/7
As you're using the Box2D World Construction Kit, I took a look at the source code (available here: https://github.com/jesses/wck). The main class seems to be BodyShape (https://raw.githubusercontent.com/jesses/wck/master/wck/BodyShape.as).
Looking through it, you should be able to access the b2Body directly. If it's null (which is probably the source of the TypeError that you're getting, then you haven't called createBody(), which is what actually takes all of your properties as creates the physical object behind the scenes.
Once you have a b2Body, if you want to position it based on the graphics, there's a function syncTransform() to do just that.
You should turn on debugDraw on your World class to make it easier to see what's going on in the background. NOTE: this needs to be done before calling create()
I was able to find solution to this problem , i found the starting point by using this -
trace(level1WorldObj.box1.b2body.GetPosition().x);
trace(level1WorldObj.box1.b2body.GetPosition().y);
then once i had the position manually i took down the coordinates and used the below code ....
level1WorldObj.box1.b2body.SetTransform(new V2(-2, 2),0 );
Thanks #divillysausages for all the help ...
Regards
Okay when I was going through different resources on Flashpunk I found three ways of adding entities to the world:
add(new Entity(10, 10));
//***************
var _entity:Entity;
//In constructor:
_entity = new Entity(10,10);
add(_entity);
//***************
FP.world.add(new Entity(10,10));
So my question is which one should I use and when.
Thank you.
add(new Entity(10, 10));
This will only work in whichever context add() is defined. I haven't used this specific library, but assuming that will be in a class called something similar to World and anything that inherits from it.
var entity:Entity = new Entity(10, 10);
add(entity);
This just breaks up the first example into two lines. It will also let you refer to that specific Entity before and after adding it to the world, whereas in the other example you have no way to reference the Entity you added.
FP.world.add(new Entity(10,10));
Here I'm assuming there's a class FP with the static property world representing a current relevant instance of the World. It does the same thing as the first example except that you can do this in any context. I would avoid using this; you'll find yourself using it as an excuse to add things to the world from unexpected locations in your code, leading to reduced code readability, frustration and a much harder debugging experience.
My preference is example 2. It's more readable, it suggests that you're using add within an appropriate context, and it lets you make changes to the Entity that you create:
var entity:Entity = new Entity();
entity.property = newValue;
add(entity);
Can someone help me to find out why I'm getting the error message "Access to undefined property: removeChild(goBack)" on the following snipped?
BTW, this is for flash CS4
function nameOfFunction() {
var goBack:backButton_mc = new backButton_mc();
goBack.x = 10;
goBack.y = 700;
goBack.back_text.text = myXML.*[buildingName].NAME;
goBack.name = "backBtn";
goBack.buttonMode = true;
addChild(goBack);
goBack.addEventListener(MouseEvent.CLICK, anotherFunction);
}
function anotherFunction(e:MouseEvent):void {
removeChild(goBack);
}
You are wrong with the scope. (surprise :-D)
The variable goBack is just defined inside of "nameOfFunction", when you try to access this from a another function like "anotherFunction" it will not exists anymore (even if it is on the display list)
There are different possibilities to solve this problem:
function anotherFunction(e:MouseEvent):void {
removeChild(e.currentTarget);
}
Or the best way would be: promote goBack as a class member of the class holding both functions. (Or if you don't use classes make goBack "global".)
Hippo is correct, but I feel it is important to explain a little more.
You created a local variable, i.e. var someVariable:DataType; within a function. This means that that variable will only be available to objects in the scope (inside) of the function (local to), and it will only last for the lifetime of the function. Soon as that function has ran the code is gone until ran again. It looks like you are probable programming directly inside the flash IDE on the time-line, which is fine, but, if you were using a document class, you could merely declare you variable in the Class scope just above the constructor function, and then set the value in the same function that your using now. This way, the reference to the variable doesn't exist within the function, it is merely set from within. This will allow that variable to be accessed from anywhere in the same class even if set to private.
This may help:
//Frame 1, Actions layer
//Slap goBack right onto the root / stage
var goBack:MovieClip;
/*
I noticed you had this data-typed differently,
i prefer to type to an interface, not an implementation.
Since your class is a movieclip in the library it extends
MovieClip and therefor IS A MovieClip, but ok either way.
*/
function nameOfFunction():void
{
goBack = new backButton_mc();
goBack.x = 10;
goBack.y = 700;
goBack.back_text.text = myXML.*[buildingName].NAME;
goBack.name = "backBtn";
goBack.buttonMode = true;
addChild(goBack);
goBack.addEventListener(MouseEvent.CLICK, anotherFunction);
}
function anotherFunction(e:MouseEvent):void
{
removeChild(goBack);
}
Scope is very important and after a while very easy to tackle. Stick with it, experiment, read up on conventions and standards that can help your development and get to loving the DocumentClass becuase even though it may be daunting to some at first, once you learn it and get used to it, it so hard to go back to programming in the flash IDE on the timeline, where I believe only display objects and audio have any place being.