cocos2d-x 中的数据结构集合(容器）(CCArray,Map,Vector)使用笔记

第1部分、CCArray

cocos2d::CCArray(在3.0中已经过时，将被vector替代）是一个可变数组集合容器，放在其中的元素是有序的，并且可以重复，可以通过索引来获得元素，可以对容器内的元素进行添加或删除。

先看看教材中的示例：

//创建数组
CCArray * array=CCArray::create();

__String *s1=__String::create("Android");

__String *s2=__String::create("iOS");

__String *s3=__String::create("cocos2d-x");

//添加元素
array->addObject(s1);
array->addObject(s2);
array->addObject(s3);

//遍历元素
ssize_t count=array->count();
for (int i=0; i<count; i++) {
__String* item=(__String*)array->getObjectAtIndex(i);
log("元素%d
%s",i,item->getCString());
}

//删除元素

array->removeObjectAtIndex(0);

log("删除0后－－－－－－－－");
ssize_t count1=array->count();
for (int i=0; i<count1; i++) {
__String* item=(__String*)array->getObjectAtIndex(i);
log("元素%d
%s",i,item->getCString());
}
运行效果如下：

元素0 Android
元素1 iOS
元素2 cocos2d-x

删除0后－－－－－－－－
元素0 iOS
元素1 cocos2d-x

下面，通过CCArray来存放26个字母，然后通过调用存放的单词来更新标签，示例如下：
首先通过CCArray申明一个数组,
CCArray* word_array=CCArray::createWithCapacity(26);
向容器中添加元素，这里添加一些字符串：

word_array->addObject(CCString::create("ant"));

word_array->addObject(CCString::create("bee"));

word_array->addObject(CCString::create("camel"));

word_array->addObject(CCString::create("dove"));

word_array->addObject(CCString::create("eagle"));

word_array->addObject(CCString::create("fox"));

word_array->addObject(CCString::create("gull"));

word_array->addObject(CCString::create("horse"));

word_array->addObject(CCString::create("i"));

word_array->addObject(CCString::create("j"));

word_array->addObject(CCString::create("k"));

word_array->addObject(CCString::create("l"));

word_array->addObject(CCString::create("m"));

word_array->addObject(CCString::create("n"));

word_array->addObject(CCString::create("o"));

word_array->addObject(CCString::create("p"));

word_array->addObject(CCString::create("q"));

word_array->addObject(CCString::create("r"));

word_array->addObject(CCString::create("s"));

word_array->addObject(CCString::create("t"));

word_array->addObject(CCString::create("u"));

word_array->addObject(CCString::create("v"));

word_array->addObject(CCString::create("w"));

word_array->addObject(CCString::create("x"));

word_array->addObject(CCString::create("y"));

word_array->addObject(CCString::create("z"));

注意当CCArray的容器建好后，如果不马上使用，需要通过retain()来进行保持，否则会被马上释放掉。

word_array->retain();

先申明一个标签： Label* lable_word;
voidLearnABC::load_word_label(){

//读取userdefault初始化字母标签

int read_seleted_idx=UserDefault::getInstance()->getIntegerForKey("selected_idx",999);

Size size=Director::getInstance()->getWinSize();
if (read_seleted_idx==999) {

lable_word=Label::createWithTTF("please
select letter!", "fonts/arial.ttf",42);
}
else{
CCObject* itemstr=NULL;
itemstr=word_array->getObjectAtIndex(read_seleted_idx);
std::string label_Str=((CCString*)itemstr)->getCString();
lable_word=Label::createWithTTF(label_Str,"fonts/arial.ttf",42);
}

lable_word->setColor(Color3B::RED);

lable_word->setOpacity(90);

lable_word->setPosition(Vec2(size.width-230,size.height*0.25));

this->addChild(lable_word);

};

刷新label标签，根据数组的索引来更新标签：

void LearnABC::refresh_word_label(ssize_t idx){
CCObject* item=NULL;

log("idx is %zd",idx);
item=word_array->getObjectAtIndex(idx);
std::string label_Str=((CCString*)item)->getCString();
lable_word->Label::setString(label_Str); //将label进行更新

}

第2部分､Vector
cocos2d::Vector<T>是一个封装好的能动态顺序访问的容器，其中的元素是按序存取的。作为cocos2d::CCArray的替代品，请优先使用，
下面是实例：

Vector<Sprite*> vector;
Sprite *s1=Sprite::create();
s1->setTag(111);
vector.pushBack(s1);

Sprite *s2=Sprite::create();
s2->setTag(222);
vector.pushBack(s2);

Sprite *s3=Sprite::create();
s3->setTag(333);
vector.pushBack(s3);

for (auto s : vector) {
log("tag---->%d",s->getTag());
}

输出结果如下：

tag---->111
tag---->222
tag---->333

即然是替代CCArray，那我们来看看是如何完全取代第1部分中的代码的吧！
首先申明vector容器：

Vector<CCString*> word_vector;

然后向容器中添加对象元素：

word_vector.pushBack(CCString::create("ant"));

word_vector.pushBack(CCString::create("bee"));

word_vector.pushBack(CCString::create("camel"));

word_vector.pushBack(CCString::create("dove"));

word_vector.pushBack(CCString::create("eagle"));

word_vector.pushBack(CCString::create("fox"));

word_vector.pushBack(CCString::create("gull"));

word_vector.pushBack(CCString::create("horse"));

word_vector.pushBack(CCString::create("i"));

word_vector.pushBack(CCString::create("j"));

word_vector.pushBack(CCString::create("k"));

word_vector.pushBack(CCString::create("l"));

word_vector.pushBack(CCString::create("m"));

word_vector.pushBack(CCString::create("n"));

word_vector.pushBack(CCString::create("o"));

word_vector.pushBack(CCString::create("p"));

word_vector.pushBack(CCString::create("q"));

word_vector.pushBack(CCString::create("r"));

word_vector.pushBack(CCString::create("s"));

word_vector.pushBack(CCString::create("t"));

word_vector.pushBack(CCString::create("u"));

word_vector.pushBack(CCString::create("v"));

word_vector.pushBack(CCString::create("w"));

word_vector.pushBack(CCString::create("x"));

word_vector.pushBack(CCString::create("y"));

word_vector.pushBack(CCString::create("z"));

voidLearnABC::load_word_label(){

//读取userdefault初始化字母

int read_seleted_idx=UserDefault::getInstance()->getIntegerForKey("selected_idx",999);

Size size=Director::getInstance()->getWinSize();
if (read_seleted_idx==999) {

lable_word=Label::createWithTTF("please
select letter!", "fonts/arial.ttf",42);
}
else{

// CCObject* itemstr=NULL;

// itemstr=word_array->getObjectAtIndex(read_seleted_idx);

// std::string label_Str=((CCString*)itemstr)->getCString();
CCObject* itemstr=NULL;
itemstr=word_vector.at(read_seleted_idx);
std::string label_Str=((CCString*)itemstr)->getCString();

lable_word=Label::createWithTTF(label_Str,"fonts/arial.ttf",42);
}

lable_word->setColor(Color3B::RED);

lable_word->setOpacity(90);

lable_word->setPosition(Vec2(size.width-230,size.height*0.25));

this->addChild(lable_word);

};

void LearnABC::refresh_word_label(ssize_t idx){

CCObject* item=NULL;

//ssize_t wordindex=idx;

log("idx is %zd",idx);

// item=word_array->getObjectAtIndex(idx);

// std::string label_Str=((CCString*)item)->getCString();

item=word_vector.at(idx);
std::string label_Str=((CCString*)item)->getCString();
lable_word->Label::setString(label_Str);
}

通过比较可以看出vector使用起来和ccarray一样方便。同时vector如果不马上使用时不会被释放掉，不需要手工进行保持。

vector.size()用来获取vector中元素的个数；
vector.at(index)用来获取索引为index的元素对象；

第3部分 map

cocos2d::Map<K,V>通过键值对方式来保存数据，元素是无序的。用来替代之前的CCDirtionary.示例如下：
Map<std::string,Sprite*> map;

std::string key1="testkey1";
Sprite* sprite1=Sprite::create();
sprite1->setTag(111);
map.insert(key1, sprite1);

std::string key2="testkey2";
Sprite* sprite2=Sprite::create();
sprite2->setTag(222);
map.insert(key2, sprite2);

std::string key3="testkey3";
Sprite* sprite3=Sprite::create();
sprite3->setTag(333);
map.insert(key3, sprite3);

std::string key4="testkey4";
Sprite* sprite4=Sprite::create();
sprite4->setTag(444);
map.insert(key4, sprite4);

Sprite* sprite=map.at(key1);
log("sprite1 tag=%d",sprite->getTag());

std::vector<std::string> keys=map.keys();
for (auto k:keys){
Sprite* s=map.at(k);
log("%s ---tag--- %d",k.c_str(),s->getTag());
}

输出结果如下：

sprite1 tag=111
testkey4 ---tag--- 444
testkey3 ---tag--- 333
testkey2 ---tag--- 222
testkey1 ---tag--- 111

｛未完待续｝