如何在Cocos2D中使对象对触摸作出反应？

Question

好的，我开始学习Coco2D了，但是我有些沮丧。我找到的很多教程都是过时的代码版本，所以当我查看它们如何完成某些任务时，我无法将其翻译成自己的程序，因为很多东西已经改变了。也就是说，我正在使用最新版本的Coco2d，即0.99版本。

我的目标是在屏幕上创建一个精灵（已完成），然后当我触摸该精灵时，“某事”会发生。现在，让我们只是让警报响起来。现在，借助朋友的帮助，我解决了这个问题。这是头文件：

// When you import this file, you import all the cocos2d classes
#import "cocos2d.h"

// HelloWorld Layer
@interface HelloWorld : CCLayer
{
 CGRect spRect;
}

// returns a Scene that contains the HelloWorld as the only child
+(id) scene;

@end

这里是实现文件：

//
// cocos2d Hello World example
// http://www.cocos2d-iphone.org
//

// Import the interfaces
#import "HelloWorldScene.h"
#import "CustomCCNode.h"

// HelloWorld implementation
@implementation HelloWorld

+(id) scene
{
 // 'scene' is an autorelease object.
 CCScene *scene = [CCScene node];

 // 'layer' is an autorelease object.
 HelloWorld *layer = [HelloWorld node];

 // add layer as a child to scene
 [scene addChild: layer];

 // return the scene
 return scene;
}

// on "init" you need to initialize your instance
-(id) init
{
 // always call "super" init
 // Apple recommends to re-assign "self" with the "super" return value
 if( (self=[super init] )) {

  // create and initialize a Label
  CCLabel* label = [CCLabel labelWithString:@"Hello World" fontName:@"Times New Roman" fontSize:64];

  // ask director the the window size
  CGSize size = [[CCDirector sharedDirector] winSize];

  // position the label on the center of the screen
  label.position =  ccp( size.width /2 , size.height/2 );

  // add the label as a child to this Layer
  [self addChild: label];

  CCSprite *sp = [CCSprite spriteWithFile:@"test2.png"];

  sp.position = ccp(300,200);
  [self addChild:sp];
  float w = [sp contentSize].width;
  float h = [sp contentSize].height;
  CGPoint aPoint = CGPointMake([sp position].x - (w/2), [sp position].y - (h/2));
  spRect = CGRectMake(aPoint.x, aPoint.y, w, h);






  CCSprite *sprite2 = [CCSprite spriteWithFile:@"test3.png"];
  sprite2.position = ccp(100,100);
  [self addChild:sprite2];



  //[self registerWithTouchDispatcher];
  self.isTouchEnabled = YES;



 }
 return self;
}


// on "dealloc" you need to release all your retained objects
- (void) dealloc
{
 // in case you have something to dealloc, do it in this method
 // in this particular example nothing needs to be released.
 // cocos2d will automatically release all the children (Label)

 // don't forget to call "super dealloc"
 [super dealloc];
}

- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
  UITouch *touch = [touches anyObject];
  //CGPoint location = [[CCDirector sharedDirector] convertCoordinate:[touch locationInView:touch.view]];
 CGPoint location = [touch locationInView:[touch view]];

 location = [[CCDirector sharedDirector] convertToGL:location];
 if (CGRectContainsPoint(spRect, location)) {
  UIAlertView *alert = [[UIAlertView alloc]
         initWithTitle:@"Win"
         message:@"testing"
         delegate:nil cancelButtonTitle:@"okay"
         otherButtonTitles:nil];

  [alert show];
  [alert release];
  NSLog(@"TOUCHES");
 }
 NSLog(@"Touch got");

}

然而，这只适用于一个对象，即我为其创建CGRect的精灵。我无法对2个精灵执行此操作，我正在进行测试。所以我的问题是：如何使屏幕上的所有精灵在触摸时都对同一事件做出反应？

对于我的程序，需要对所有相同类型的对象运行相同的事件，因此这应该会让它变得更容易。我尝试制作CCNode的子类并覆盖该方法，但根本不起作用...所以我做错了什么。希望能得到帮助！

浏览cocos2D中的“Touches”项目，看看是否能找到他们是如何做到的。看起来他们制作了一个子类并重写了方法：

- (BOOL)ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event
- (void)ccTouchMoved:(UITouch *)touch withEvent:(UIEvent *)event
- (void)ccTouchEnded:(UITouch *)touch withEvent:(UIEvent *)event

现在我需要弄清楚为什么我的不起作用...嗯...

- Ethan Mick

Answer 1

我明白了。我需要在自定义类中添加更多的代码：

头文件：

//
//  CustomCCNode.h
//  Coco2dTest2
//
//  Created by Ethan Mick on 3/11/10.
//  Copyright 2010 Wayfarer. All rights reserved.
//

#import "cocos2d.h"


@interface CustomCCNode : CCSprite <CCTargetedTouchDelegate> {

}

@property (nonatomic, readonly) CGRect rect;


@end

实现：

//
//  CustomCCNode.m
//  Coco2dTest2
//
//  Created by Ethan Mick on 3/11/10.
//  Copyright 2010 Wayfarer. All rights reserved.
//

#import "CustomCCNode.h"
#import "cocos2d.h"


@implementation CustomCCNode

- (CGRect)rect
{
    CGSize s = [self.texture contentSize];
    return CGRectMake(-s.width / 2, -s.height / 2, s.width, s.height);
}



- (BOOL)containsTouchLocation:(UITouch *)touch
{
    return CGRectContainsPoint(self.rect, [self convertTouchToNodeSpaceAR:touch]);
}

- (void)onEnter
{
    [[CCTouchDispatcher sharedDispatcher] addTargetedDelegate:self priority:0 swallowsTouches:YES];
    [super onEnter];
}


- (void)onExit
{
    [[CCTouchDispatcher sharedDispatcher] removeDelegate:self];
    [super onExit];
}   





- (BOOL)ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event
{
    NSLog(@"ccTouchBegan Called");
    if ( ![self containsTouchLocation:touch] ) return NO;
    NSLog(@"ccTouchBegan returns YES");
    return YES;
}

- (void)ccTouchMoved:(UITouch *)touch withEvent:(UIEvent *)event
{
    CGPoint touchPoint = [touch locationInView:[touch view]];
    touchPoint = [[CCDirector sharedDirector] convertToGL:touchPoint];

    NSLog(@"ccTouch Moved is called");
}

- (void)ccTouchEnded:(UITouch *)touch withEvent:(UIEvent *)event
{
    NSLog(@"ccTouchEnded is called");
}


@end

- Ethan Mick

---

那么，你如何使用 PNG 文件实例化这个新类呢？ - Moe Salih

你还需要知道吗？这只是CCSprite的一个子类，所以： CCSprite *aSprite = [CCSprite spriteWithTexture:[在此添加CCTexture的png]]; - Ethan Mick

你也可以使用boundingBox属性代替自定义的rect方法。 - Tomas Andrle

请注意，我认为这可能是更好的方法，除非我漏掉了什么：-(BOOL) containsTouchLocation:(UITouch*)touch { CGPoint touchNodeSpace = [self convertTouchToNodeSpace:touch]; return CGRectContainsPoint(CGRectMake(0, 0, [self contentSize].width, [self contentSize].height), touchNodeSpace); } - Archagon

这样，您就不会假定锚点为0.5, 0.5，并且始终从0, 0测量触摸。 - Archagon

Answer 2

我是一个初学者，但这个文件帮了我很多忙，现在我理解了更多的东西，正确实例化的方法是：（至少我是这样做的）

+(id)scene{
    CustomCCNode *myNode = [CustomCCNode spriteWithFile:@"myPng.png"];
    myNode.position = ccp(150,150);
    [scene addChild:myNode];
    return scene;
}

打开控制台并查看触摸事件触发时发送的消息。

- makAndShees