I'm trying to schedule selectors with CCCallFunc but the selector isn't getting called.
This works:
[self launchCreature];
This does not:
id launchCreatureAction = [CCCallFunc actionWithTarget:self selector:#selector(launchCreature)];
[self runAction:launchCreatureAction];
launchCreature is defined in the parent class, and the CCCallFunc works when used in the parent class. Nothing is showing up in the debugger when I run the action; it just doesn't run the code. (It never hits the breakpoint I have defined at the first line of launchCreature.)
Am I missing about something about how to use CCCallFunc, or how self works in subclasses?
Edit: I misremembered how my code is set up. launchCreature and the code above are BOTH defined in the parent class. The difference between working and not working is that it worked in an instance of the parent class, but doesn't work in an instance of the subclass. This no longer seems to work in the parent class either. Sorry for the confusion.
It works for me. You could try making a call to [super launchCreature] in [self launchCreature] in the subclass and see if the break point is being hit.
Related
Could someone help me, I am trying to access a CCLabelTTF that resides in a CCLayer subclass(GameLayer), but I want to access it from another Player class(also a CCLayer). I thought
[self getChildByTag: DEBUG_LABEL];
searches the scene and finds the object that matches it and returns a pointer to it, since all objects are stored in a tree data structure.
I was able to access the label through trial and error using the follwing code but would appreciate if someone could advise if I am not understanding the getChildByTag method or if there is a way of searching the scene for an object without using the code below.
CCLabelTTF *lbl = (CCLabelTTF *)[[[[CCDirector sharedDirector] runningScene] getChildByTag: GAME_LAYER_TAG] getChildByTag: DEBUG_LABEL_TAG];
Please advise.
getChildByTag only checks direct children of the parent CCNode calling it. It will not check children's children (grandchildren, if you will).
For example, if your node hierarchy looks like this:
MyCCLayer1->MyCCLayer2->MyCCSprite->MyCCLabel
Calling MyCCLayer1 only has direct access to MyCCLayer2 via the getChildByTag call. In turn, MyCCLayer2 could call getChildByTag to get MyCCSprite, and then MyCCSprite could call getChildByTag to get MyCCLabel.
EDIT: I am using ARC
In my code (based on the ShootEmUp example in this book, which I highly reccomend, source code in chapter 8 available here) I often use the trick of accessing the GameScene via:
+(GameScene*) sharedGameScene;
which returns a reference to the static instance of GameScene and is used by all children of GameScene (e.g. ShipEntity, InputLayer.. etc..) to dialog with GameScene (EDIT: aka singleton instance of GameScene).
To create multiple levels I thought of implementing a method calledsceneWithId:(int) method where I load different level data each time.
EDIT: Code snippet of init method:
-(id) initWithId:(int)sceneId
{
CCLOG(#"scene With id");
if ((self = [super init]))
{
//All common initialization happens here..
switch (sceneId) {
case 1:
[self loadFirstLevelData];
break;
case 2:
[self loadSecondLevelData];
break;
default:
[self loadSecondLevelData];
break;
}
//Other common stuff..
[self setUpCounters];
[self setUpWeaponsMenu];
[self scheduleUpdate];
[self schedule:#selector(timerUpdate:) interval:1];
InputLayerButtons* inputLayer = [InputLayerButtons node];
[self addChild:inputLayer z:1 tag:GameSceneLayerTagInput];
}
EDIT: Is that init method ok? I have found this post which uses dispatch_once. Should I do the same?
Or should I pheraps create a GameScene class and then sublcass it?
E.g. FirstGameScene : GameScene
EDIT: I have followed the advice of #LearnCocos2D and used the cleanup method, and I used it to stop a singleton object music layer to play (the MusicLayer object is initialized in AppDelegate and I meant to use it to "manage" the music across all scenes - the problem was that without stopping it in dealloc it would have kept playing the music that was loaded at init time).
-(void) loadFirstLevelData{
//HERE WILL LOAD ALL SPECIFIC ELEMENTS: ENEMIES, BONUSES etc..
//AS WELL AS THE MUSIC FOR THE LEVEL
[[MusicLayer sharedMusicLayer] _loadMusic:#"1.mp3"];
[[MusicLayer sharedMusicLayer] playBackgroundMusicFile: #"1.mp3"];
}
-(void) cleanup
{
//Should I remove all child loaded in LoadLevelData??
CCLOG(#"cleanup GameScene");
[[MusicLayer sharedMusicLayer] stopAllMusic];
//MusicLayer is not a child of GameScene but of AppDelegate - the idea is to keep loading and unloading music files - sometimes I need to keep playing the file between scenes and hence I used the singleton pattern for this as well..
[super cleanup];
}
But I still have some doubts:
Is it ok to have several loadLevelData methods in GameScene class? Each method can be 200 lines long! I tried to sublcass GameScene but is a bit messy. I explain better. I imported "GameScene.h" in the header file of the subclass and by doing so I expected that if I had ovverriden only certain methods (e.g. init) I would have been able to see the various classes imported in GameScene (e.g. InputLayerButtons). It is not the case. So I probably don't understand how imports work in Objective-C
Is it ok to remove specifc children in the cleanup method? I thought that I would remove all child that are added in the LoadLevelXXXData method to reduce the memory usage.
I have set a bounty for this question but I will probably need to test the answer and re-edit as I don't have a clear enough understanding of the subject to be super precise in the question. Hope is ok.
PS: Would be great if someone would feel like sharing a UML style diagram of a Cocos2D Shooter Game where with various levels and GameScene using singleton pattern :).
I'll focus on the questions on the bottom:
Is it ok to have several loadLevelData methods in GameScene class? Each method can be 200 lines long! I tried to sublcass GameScene but
is a bit messy. I explain better. I imported "GameScene.h" in the
header file of the subclass and by doing so I expected that if I had
ovverriden only certain methods (e.g. init) I would have been able to
see the various classes imported in GameScene (e.g.
InputLayerButtons). It is not the case. So I probably don't understand
how imports work in Objective-C
There's nothing wrong with having long methods. However I suspect your loading methods perform very similar routines, so you should check if you can generalize these into subroutines. A good indicator is if several lines of code are absolutely identical except for the parameters or variable names. The best practice is to write identical code only once, and execute it many times with varying parameters.
The #import statement is used to allow the compiler to "see" other classes. Without importing other header files, you couldn't use that class' methods and properties without the compiler complaining.
2 . Is it ok to remove specifc children in the cleanup method? I thought that I would remove all child that are added in the
LoadLevelXXXData method to reduce the memory usage.
It makes no sense to remove children during cleanup. Cocos2D removes all children during cleanup automatically.
If that does not seem to be the case for you, you have a retain cycle somewhere that prevents child nodes from deallocating.
sorry for answering this but I have been experimenting and decided to:
not use the singleton pattern for GameScene
use, insteada a singleton object to keep all shared data
My implementation draft for the GameScene (now called ShooterScene) is the following (I followed some advices in a cocos2d-iphone forum post as well as this other one ):
#import "ShooterScene.h"
#import "LevelData.h"
#import "HudLayer.h"
#interface ShooterScene (PrivateMethods)
-(void) loadGameArtFile;
#end
#implementation ShooterScene
+ (id) sceneWithId:(int)sceneId
{
CCScene *scene = [CCScene node];
ShooterScene * shooterLayer = [ShooterScene node];
[scene addChild:shooterLayer];
[shooterLayer loadGameArtFile];
LevelData * levelData = [LevelData node];
[shooterLayer addChild:levelData];
switch (sceneId) {
case 1:
[levelData loadLevelDataOne];
break;
case 2:
[levelData loadLevelDataOne];
break;
default:
break;
}
HudLayer * hud = [HudLayer node];
[hud setUpPauseMenu];
[shooterLayer addChild:hud];
return scene;
}
I am using the update method of ShooterScene to manage the all the game events (E.g. spawning, checking collisions, moving the background layer). I haven't put the full implementation here as is still work in progress, but is just to have an idea of the type of answer I am finding useful.
I have two CCMenu instances. At some point in the game, menu A is overlapped by menu B. However, when I press a button within menu B, the one that "gets it" is menu A.
How can I give touch priority to CCMenu B?
I tried this:
[[CCTouchDispatcher sharedDispatcher] setPriority:-130 forDelegate:menuB];
However, Xcode says that this delegate (menuB) was not found.
Okay, I fixed this, but I still think there should be a better way.
First, we have to edit CCMenu's interface. We have to create a new integer property.
#interface CCMenu : CCLayer <CCRGBAProtocol>
{
tCCMenuState state_;
CCMenuItem *selectedItem_;
GLubyte opacity_;
ccColor3B color_;
int extraTouchPriority; // Our new integer
}
#property (readwrite) int extraTouchPriority;
Now change the registerWithTouchDispatcher method to this:
-(void) registerWithTouchDispatcher
{
[[CCTouchDispatcher sharedDispatcher] addTargetedDelegate:self priority:kCCMenuTouchPriority - extraTouchPriority swallowsTouches:YES];
}
Done. Now, when you have to give your CCMenu instance more priority than others, just give a higher extraTouchPriority value to it after initializing it.
I had the same problem. What i did is copied the entire CCMenu from cocos2d library, renamed it and then modified kCCMenuTouchPriority to what i wanted. Note that you have to rename kCCMenuTouchPriority for the custom menu. I used kkCCMenuTouchPriority.
I called it in code like this:
CCMenuPopUp *menu =[CCMenuPopUp menuWithItems:item1,nil];
I tried to subclass it but i ran into some problems and gave up and gone with the solution above.
the CCTouchDispatcher thing doesn't work because the menu isn't inited yet when you call it
Here's anoter variation on one of the anwers above, which doesn't alter the cocos2D code base, because that is bad practice: https://gist.github.com/tudormunteanu/6174624
I have a CCRepeatForever action with a tag of 20. I call this:
[player stopActionByTag:20];
Noting happens.
I call this:
[player stopAllActions];
It stops. Any idea? The action is created like this and runs fine:
CCRepeatForever *repeat=[CCRepeatForever actionWithAction:animate];
repeat.tag=20;
[player runAction:repeat];
update: i also tried setting animate.tag=21 and stopping that action by itself or in addition to the repeat action, but neither works.
This should work, I made a quick test with stopActionWithTag using CCRepeatForever and it stops it correctly.
I can only imagine two cases where it wouldn't work:
You have more than one action with the tag = 20 running on the same object.
The object you send runAction to is a different object than the one you send stopActionByTag to.
The former is easy to check. If this code fixes your problem, you're running multiple actions with the same tag on the player object:
while ([player getActionByTag:20]) {
[player stopActionByTag:20];
};
The latter is rather unlikely but possible. One way to find out is to set a breakpoint on the runAction line and note the address of the player variable. Then set another breakpoint at the stopActionByTag line and compare that player's address with the previous one. If they're not the same, then that would be the problem.
I am totally new to cocos2d and Objective C. I just started studying the HelloWorld example that came with cocos2d package, and just couldn't figure out where in the application the -init() function within HelloWorldScene.m is getting called.
Here is the tutorial that I was following:
http://www.bit-101.com/blog/?p=2123
Thanks in advance!
jtalarico is correct. I'd like to expand on his answer a bit.
In general, some form of [init] is called by convention whenever an object gets instantiated. For many objects, [init] is all that is needed, but some objects have more complex forms, such as [initWithSomething].
In Cocos2d, the init function is generally called by the [node] method, which is often used to construct an object in Cocos2d. For example, look in CCNode.m, and you will see this code:
+(id) node
{
return [[[self alloc] init] autorelease];
}
Other objects have other constructors, but this is the main example.
So, if you subclass CCNode, you can override the [init] method and do your own stuff when an object gets created. Just be sure to call [super init] so that CCNode can do its own initialization, too.
The init() method is being overridden in the scene. It is getting called within the base class when an instance of the scene is created. By overriding it, you get the opportunity to fire your own code.