I just Implemented ads for Android in my game using this guide.
It works fine, I have an interface in my core project that the Android Activity implements.
However my problem is that you need to send this implemented interface to the core project, and then pass it as a parameter to your first Screen, where you can use it, ex:
public MyGdxGame(PlatformSpecific ps) //Android class that handle fb-login and ads
{
this.ps = ps;
}
#Override
public void create ()
{
setScreen(new LoginScreen(this, ps);
}
This was fine for when I needed fb-login since I'm using that in the LoginScreen, but I want to be able to create my ads in other Screens (after a game is finished) by calling createAd-method in interface.
Do I have to keep passing ps between all the Screens just so I can use it in a Screen that only gets used quite rarely, or is there some way to get to this interface from my Screen without passing it to the constructor? Kind of like when you initiate an object, ex:
private PlatformSpecific ps = new PlatformSpecific();
Or does LibGdx have some library to support this scenario maybe? Worst case I could just pass ps between all constructors but feels like a pretty ugly solution.
Solution 1:
Store PlatformSpecific in a global static variable. That allows you to access anywhere in your code without passing it in every constructor.
Soluatio 2:
Have MyPlatformContext class which provides access to PlatformSpecific. Then pass this MyPlatformContext object to your screen constructors. If you extend your platform specific code later you do not have to change the screen constructors. Just edit MyPlatformContextMyPlatformContext class.
Pseudo code:
class MyPlatformContext {
private FacbookPlatform fb;
private AdmobPlatform admob
FacbookPlatform getFacebook() {
return fb;
}
...
}
Related
I want to create a controller based JavaFX GUI consisting of multiple controllers.
The task I can't accomplish is to pass parameters from one Scene to another AND back.
Or in other words:
The MainController loads SubController's fxml, passes an object to SubController, switches the scene. There shall not be two open windows.
After it's work is done, the SubController shall then switch the scene back to the MainController and pass some object back.
This is where I fail.
This question is very similar to this one but still unanswered. Passing Parameters JavaFX FXML
It was also mentioned in the comments:
"This work when you pass parameter from first controller to second but how to pass parameter from second to first controller,i mean after first.fxml was loaded.
– Xlint Xms Sep 18 '17 at 23:15"
I used the first approach in the top answer of that thread.
Does anyone have a clue how to achieve this without external libs?
There are numerous ways to do this.
Here is one solution, which passes a Consumer to another controller. The other controller can invoke the consumer to accept the result once it has completed its work. The sample is based on the example code from an answer to the question that you linked.
public Stage showCustomerDialog(Customer customer) {
FXMLLoader loader = new FXMLLoader(
getClass().getResource(
"customerDialog.fxml"
)
);
Stage stage = new Stage(StageStyle.DECORATED);
stage.setScene(
new Scene(
(Pane) loader.load()
)
);
Consumer<CustomerInteractionResult> onComplete = result -> {
// update main screen based upon result.
};
CustomerDialogController controller =
loader.<CustomerDialogController>getController();
controller.initData(customer, onComplete);
stage.show();
return stage;
}
...
class CustomerDialogController() {
#FXML private Label customerName;
private Consumer<CustomerInteractionResult> onComplete
void initialize() {}
void initData(Customer customer, Consumer<CustomerInteractionResult> onComplete) {
customerName.setText(customer.getName());
this.onComplete = onComplete;
}
#FXML
void onSomeInteractionLikeCloseDialog(ActionEvent event) {
onComplete.accept(new CustomerInteractionResult(someDataGatheredByDialog));
}
}
Another way to do this is to add a result property to the controller of the dialog screen and interested invokers could listen to or retrieve the result property. A result property is how the in-built JavaFX dialogs work, so you would be essentially imitating some of that functionality.
If you have a lot of this passing back and forth stuff going on, a shared dependency injection model based on something like Gluon Ignite, might assist you.
I've used AfterBurner.fx for dependency injection, which is very slick and powerful as long as you follow the conventions. It's not necessarily an external lib if you just copy the 3 classes into your structure. Although you do need the javax Inject jar, so I guess it is an eternal reference.
Alternately, if you have a central "screen" from which most of your application branches out you could use property binding probably within a singleton pattern. There are some good articles on using singleton in JavaFX, like this one. I did that for a small application that works really great, but defining all of those bindings can get out of hand if there are a lot of properties.
To pass data back, the best approach is probably to fire custom Events, which the parent controller subscribes to with Node::addEventHandler. See How to emit and handle custom events? for context.
In complex cases when the two controllers have no reference to each other, a Event Bus as #jewelsea mentioned is the superior option.
For overall architecture, this Reddit comment provides some good detail: https://www.reddit.com/r/java/comments/7c4vhv/are_there_any_canonical_javafx_design_patterns/dpnsedh/
I have an application which will be using large numbers of assets. In order to better handle that I chose to use a registry to hold all the assets so they are accessible across the entire application:
package
{
public class SpriteRegistry
{
public static var SPRITENAME = "link to image file";
public function SpriteRegistry()
{
}
}
}
What I would like to do is create an XML document and list off the file name and link so that when the application starts, this registry creates its variables which are freely accessible from that list without me needing to hard code any content directly into it.
Specifically what I need to know is how to get the "public static" effect or how to get an equivalent effect for variables that I CAN dynamically produce.
More info:
I am using a function that loads a sprite texture into a sprite object based on a string variable called mouseAttribute:
loadGraphic(SpriteRegistry[currentAttribute+"Texture"]);
Basically it's like a painting program but for a level editor for a video game.
The problem is that I'm eventually going to have 100+ sprites that I need to application to load and then I need the loadGraphic function to still be able to point effectively to the target sprite.
The library I'm using also needs me to embed the source into a class before I can pull it into the sprite object:
[Embed(source = "/Images/GridTile.png")]
public static var gridTileTexture:Class;
The reason I'm trying to avoid an array is because it means that I will have to search through an array of 100+ objects to find one sprite every time I click a single grid on the editor. That is going to chug.
It's very simple - just use a static function, which will return the XML. So you will need to load the XML file somehow (you decide where, but your registry class should have reference to it). Something similar to this:
private static var _xml:XML;
public static function initialize(xml:XML):void {
_xml = xml;
}
public static function getXML():XML {
return _xml;
}
So you will use it like that:
SpriteRegistry.initialize(loadedXML); // done only once when you initialize your app
trace(SpriteRegistry.getXML().someValue); // someValue is directly from the XML
It's a common used strategy and most of the times you would have something like an app initializer - something to load and instantiate all the things, then pass them to some registries that keep them stored for faster and global usage.
Edit:
After reading your further comments, I can't see any big change - everything would be ok with this resolution.
If you are worried about the 'need to search through array' - just do it as an object! This way you will be able to directly access the proper one using a key exactly like you pointed:
private static var _registry:Object;
public static function initialize(xml:XML):void {
// loop through xml and insert items
_registry[key] = resource;
}
public static function getResource(id):Object {
return _registry[id];
}
This way you can use it like:
SpriteRegistry.getResource(currentAttribute+"Texture");
My personal opinion is that you should avoid statics wherever possible. Instead, you should just create a single instance and provide it through dependency injection where needed.
If you were to go with that approach, you could do something like:
public function getSprite(spriteName:String):Class{
return this[spriteName];
}
or
public function getSprite(spriteName:String):Class{
return yourDictionaryOrObject[spriteName];//I'd implement it this way
}
Otherwise you could go with something like:
public static function getSprite(spriteName):Class{
return ThisHonkingBigUnnchangeableClassname[spriteName];
}
What I would not do is create a Dictionary in a static-only Class, because you're almost inevitably going to wind up with global mutable state.
Discussion, per request
Why would you want to create an instance and pass it, rather than hard-code a reference to a specific Class? A lot of the answers are covered in the global mutable state link above, but here are some that are specific to this kind of problem:
Flexibility. Say you build everything with the idea that you'd only have one set of resources being used in parallel, then you discover you need more than one--for example you might need one for color blind users, or multiple languages, or thumbnails vs. full-sized. If you hard-code to a static, then you'll have to go in every place that was hard-coded and make some sort of change to use a different set, whereas if you use DI, you just supply a different instance loaded with different resources, and done.
Testability. This is actually covered in the link, but I think it bears pulling out. If you want to run a quick test on something that needs a resource, you have to have that static "thing" and you can't change anything about it. It then becomes very difficult to know if the thing you're actually testing is working or if it just appears to be working based on the current implementation of the "thing."
Resource use: everything about an all-static Class exists from the time the swf loads to the time it unloads. Instances only exist from when you instantiate them until they are garbage collected. This can be especially important with resource files that contain embedded assets.
I think the important thing about Frameworks is to realize how they work. The major ones used in ActionScript work the same way, which is they have a central event dispatcher (event bus) that anything loaded to the framework can get a reference to by declaring an interest in it by asking for it to be injected. Additionally, they watch the stage for an event that says that something has been added (in RL it's ADDED_TO_STAGE, whereas in Mate it's the Flex event CREATION_COMPLETE). Once you understand these principles, you can actually apply them yourself with a very light hand without necessarily needing everything that comes along with a framework.
TL;DR
I usually try to avoid answering questions that weren't asked, but in this case I think it would be helpful to discuss an entirely different approach to this problem. At root, the solution comes down not to injecting an entire resource instance, but instead just injecting the resource that's needed.
I don't know what the OP's code is like, but this solution should be general enough that it would work to pass named BitmapDatas to anything that implements our Interface that is capable of dispatching against whatever IEventDispatcher we set as the eventBus (this could be the stage, a particular DisplayObject, or an EventDispatcher that is created just for the purpose.
Note that this code is strikingly similar to code I have in production ;).
public class ResourceManager {
//this can be loaded dynamically, or you can create subclasses that fill the registry
//with embedded Classes in the constructor
protected var registry:Dictionary = new Dictionary();
protected var _eventBus:IeventDispatcher;
public function registerResource(resourceName:String, resourceClass:Class):void {
var bitmap:BitmapData = new resourceClass as BitmapData;
if (resourceClass) {
registry[resourceName] = bitmap;
} else {
trace('Class didn\'t make a BitmapData');
}
}
public function getResource(resourceName:String):BitmapData {
var resource:BitmapData = registry[resourceName];
if (!resource) trace('there was no resource registered for', resourceName);
}
public function get eventBus():IEventDispatcher {
return _eventBus;
}
public function set eventBus(value:IEventDispatcher):void {
if (value != _eventBus){
if (_eventBus) {
_eventBus.removeEventListener(YourCustomEvent.GET_RESOURCE, provideResource);
}
_eventBus = value;
if (_eventBus) {
_eventBus.addEventListener(YourCustomEvent.GET_RESOURCE, provideResource);
}
}
}
protected function provideResource(e:YourCustomEvent):void {
var client:IBitmapResourceClient = e.target as IBitmapResourceClient;
if (client) {
client.resource = getResource(e.resourceName);//your custom event has a resourceName property that you populated when you dispatched the event.
}
}
}
Note that I didn't provide the Interface or the custom event or an example implementation of the Interface due to the fact I am on my lunch break, but if anyone needs that to understand the code please post back and I'll fill that in.
I am in the midst of creating the architecture for my new Point and Click game in the Starling framework. It is set to be big in size, so I am trying to make sure to use best Object Oriented practises to ensure I do not A) Repeat the same methods. B) Keep it sustainable and clean.
I was unaware of Interfacing as a way to contract all classes. To keep everything consistent and to ensure that sub classes have the methods to function correctly. Let us look at an example of a player class i have created.
public interface IPlayer {
function changeDirection():void;
function walkToPosition():void;
function pickUpItem():void;
}
class AbstractPlayer extends Sprite implements IPlayer {
public function changeDirection():void {}
protected function walkToPosition():void {}
protected function pickUpItem():void {}
}
class Player extends AbstractPlayer {
override protected function walkToPosition():void {}
override protected function pickUpItem():void {}
}
I am aware that AS3 Does not support Abstract Classes natively. But I choose to have it in this form as it makes sense to. What I do not understand is why the interfaces only support public methods. Doesn't that defeat the whole purpose of having an interface; so you know what methods are needed for a player. Declaring only the public functions of the player class seems like a half job.
A verbose explanation of this concept and perhaps a more advanced solution to how this could be structured would be of great benefit.
Many Thanks,
Shaun
An interface is a collection of method declarations that allows unrelated objects to communicate with one another.Hence public access control identifiers for implemented methods.In a typical interactive context often a need arises to modify or control behavior of an object in question externally.In such a case, behavior-control may ideally be accomplished through an interface.Obliviously only methods put into a public namespace are accessible externally.Bearing in mind that attributes of an object should not be be directly modified by external code but only through an interface is good practice of Object Oriented Design. Assuming that a need arises of an object to have more than one point of access control(behavior control); one for external purposes and the other for internal purposes respectively, then putting all behavior in one interface defeats the objective.The following may help to achieve the objective(because you said it's big in size).
Put behavior in an interface you think should be accessible externally.
Define Mediator to encapsulate view-code-mediation:-listen for user triggered events, update view send notifications to other tiers of the application.
Define Model for data purposes.
Define executable commands to be called within your application.
See if you can promote as much lose coupling as possible among the tiers.The goal is to write as much less code as possible and not boiler-plate in nature.I recommend that you use a framework such as robotlegs if really your project is that big.The framework will take care of dependency injection and along the way lift off the burden of writing boiler-plate code.
I Hope the foregoing helps. Thanks.
The interface is acting as an outline of required members to be implemented in the classes using said interface. Therefore the interface methods never being called directly and only being used in the classes implementing them require no access modifiers.
Now you're correct AS3 does not support abstract classes, BUT there is a way to implement an "abstract" class AS3 as per the design. So here is what that might look like with your code:
public interface IPlayer
{
function init():void;
function changeDirection():void;
function walkToPosition():void;
function pickUpItem():void;
}
public class AbstractPlayer extends Sprite implements IPlayer
{
public function AbstractPlayer() {
init();
}
protected function init():void {
throw new IllegalOperationError( "Abstract method, must be overridden in subclass" );
}
public function changeDirection():void {}
protected function walkToPosition():void {}
protected function pickUpItem():void {}
}
public class Player extends AbstractPlayer
{
public function Player() {
super();
}
override protected function init():void {
//implementation
}
}
Abstract classes having method implementation by default will require subclasses to override these methods ( see init() and error thrown ) keeping strict usage of the parent class method and members.
This is the basic abstract class design for AS3. This is also the begining to a Factory Method pattern which you can read more on here: http://www.adobe.com/devnet/actionscript/articles/ora_as3_design_patterns.html
Now the more reusable design for this might be to generalize your class names a bit more, perhaps something more like this:
public interface IEntity
{
function init():void;
function changeDirection():void;
function walkToPosition():void;
}
This would be assuming that more game objects other than your Player class will have use of the methods in the IEntity interface.
Now your Player class can become a new object of type Entity:
public class Entity extends Sprite implements IEntity
{
public function Entity() {
init();
}
protected function init():void {
throw new IllegalOperationError( "Abstract method, must be overridden in subclass" );
}
public function changeDirection():void {}
protected function walkToPosition():void {}
protected function pickUpItem():void {}
}
Now in regards to the design, since abstract classes are just a tool like any other there are many different designs to take using it and it really depends on your project. I would recommend sifting through the aforementioned link to the "Factory Method" pattern and some of the other designs to see what fits your needs.
An interface defines the way other classes interact with a specific implementation of that interface. Other classes cannot call implementation's private methods directly - there's no need for the interface to define them.
Let's say we have two subclasses of AbstractPlayer: Player and AIPlayer. The Player class would probably include methods to listen for specific input events and to respond to them accordingly, like onKeyUp or onMouseClick, which should be private: there's no need to external classes to know how the player is controlled. The AIPlayer on the other hand is controlled by some strategies you define in your code, therefore instead of listening to user's input, it should keep track of Player's actions and react accordingly. This class does not need onKeyUp or onMouseClick methods, so why put them in interface?
Currently I'am developing a game using cocos2d-x.
Of course, for multi-platform use.
basically I use a xcode for coding and development.
I want to attach IAP(In app purchases) separately to each coding for iPhone and Android
Problem to try to call a function of a certain class in Android that did not work.
Sources include the following:
cpp side
MyClass::invoke_init()
{
JavaVM* jvm = JniHelper::getJavaVM();
JNIEnv* env;
jvm->GetEnv((void **) &env, JNI_VERSION_1_2);
jclass cls;
jmethodID method;
cls = env->FindClass("com/joycestudios/game/SampleActivity");
method = env->GetMethodID(cls, "initFunc", "()V");
env->CallVoidMethod(cls, method);
}
java side
public class SampleActivity extends Cocos2dxActivity
{
public void initFunc()
{
Log.v("LOG_INFO", "initFunc()");
}
}
The first test as follows: I'm in progress.
build from xcode and build from build_natvie.sh and last build from eclipse.
But after run on eclipse, Just black screen and shuts down.
How to call a function of a java class?
What I looked at several samples, including also analyze the problem, I do not see any problems?
Can you tell if you find any error log?
First check if your game is working fine on android..
Den we can have a look how to call the function.
Generally for calling native method I use MessageJni class available in Cocos2d-x library.
I create my methods in MessageJni class which calls for native methods.
Its easy and convenient way of calling native methods.
Just google using MessageJni class. It will ease your work.
:)
I currently pass a reference to my model through the constructor to any class that needs it in my simple mvc pattern, this can get annoying at times when it starts to go deeper.
How do Classes such as LoadMax allow you from anywhere to simple import the class, and do something like addChild(LoaderMax.getContent("bg"));? Replicating this should surely be a good way to have my model work, without the complexity of big frameworks?
Statics are your friend
As previous answers have noted, TweenLite/Max etc. makes heavy use of static members to get work done. This is exactly like the Math class, for example, and can be a very convenient design pattern. You have global access to the class, and that can definitely alleviate the issue of getting access to variables through deeply nested classes.
Statics are the enemy
Statics, however, bring certain problems to the table. Most importantly, they tend to reduce flexibility and modularity of classes through the often unnecessary addition of tightly coupled relationships. It's a bit like pouring concrete over your application. It does work, but changing behavior becomes difficult as project features change.
Static members != instance members
Note, very clearly, that a static member "belongs" to the class itself, and not an instance of that class. Static members have no access to instance members. This causes troubles when you want to mix these members up in logic. You tend to have to make everything static (the so-called "static-cling" effect). Static patterns are often argued to be argued to be "anti" object-oriented, for precisely this reason. Once you build a structure on a static pattern you tend to lose many of the principles that makes OOD powerful.
In small does, they're pretty nice
That all being said - TweenLite is a great example of a static pattern that is totally appropriate - its a utility package, one that logic is not dependent on. And that should probably be how you leverage statics, too.
To reduce reliance on statics, or even global vars, it does often mean writing more code, but the flexibility in app structure gained is often quite worth it. #Marty_Wallace has a pretty good solution imo.
Demeter and the Paperboy
Finally, I'll just mention the Law of Demeter, or the Principle of Least Knowledge, and the related Paperboy and the Wallet example, which is often pointed to in discussions of statics:
Each unit should have only limited knowledge about other units: only
units "closely" related to the current
unit.
Each unit should only talk to its friends; don't talk to strangers.
Only talk to your immediate friends.
Hopefully that sheds a little bit of light on a fairly complicated and not-often obvious issue.
This is done using the static namespace, however I discourage the use of this.
package
{
public class Main
{
public static function sayHell():void
{
trace("hello!");
}
}
}
You can now call sayHello() like this from anywhere in the application (assuming you've imported the class).
Main.sayHello();
Another thing you can do (to make the entire class accessible from within the application) is create a static property that refers to the class itself:
package
{
public class Something
{
public static var instance:Something;
public function Something()
{
instance = this;
}
public function someFunction():void
{
trace('hello!');
}
}
}
Which you can now use like so:
Something.instance.someFunction();
The only thing to note here is that you need to create an instance of Something for this to work to call the constructor and define instance.
What I would do
Create a base class for all objects in your application
Create a manager class that takes care of these objects
Create a setter within your base class to define the manager
Here's an example:
Base
package
{
public class Base extends Object
{
private var _manager:Manager;
public function set manager(m:Manager):void
{
_manager = m;
init();
}
protected function init():void
{
manager.someFunction();
}
public function get manager():Manager{ return _manager; }
}
}
Manager
package
{
public class Manager extends Object
{
public function someFunction():void
{
trace('hello!');
}
}
}
Now anything that extends Base will have access to anything held in Manager via the manager getter property. All you need to do is make sure you define the manager, which is easily achieved from within anything that extends Base like so:
var something:SomeExtendingClass = new SomeExtendingClass();
something.manager = manager;
The example you gave is just a static method, but to answer your question about a global instance of a class:
package myPackage
{
public var globalVariable:MyClass = new MyClass();
}
You can access it with:
import myPackage.globalVariable;
trace(globalVariable);
I think you have to rethink in which way you want to name your classes.
You can instantiate whatever class you want, at run-time, but to access a instance by name, you have to make changes in your structure. For example, the getContent() function you mentioned in LoaderMax, all it does is to search in an array for the given loader that matchs the name, among other things. You can read the name variable comment for a description.
A name that you use to identify the loader instance. This name can be fed to the getLoader() or getContent() methods or traced at any time. Each loader's name should be unique. If you don't define one, a unique name will be created automatically, like "loader21".
So in this system, you have to name every single member (loaders in this case) if you want to be able to search them. Because if I call getClassInstance("myinstance"), what is "myinstance" representing? Where should I name it?
That said, if you want to do it for DisplayObjects only, you can use getChildByName. But again, you have to name every DisplayObject (just set the name variable).
Hope this helps.