【cocos2d-x 手游研發小技巧（5）獲取網絡圖片緩存並展示】

今天是年前最后一天上班了，最后一天上班，祝大家馬上有各種東西，最后一天也給寫一點干貨，就是獲取網絡圖片；

經過自己簡單封裝了一下，實現了獲取網絡圖片，按照比例展示出來，實現方法是cocos2dx - http的異步方法，相信有很多地方都會使用

到着這個需求；比如獲取玩家的頭像。

我就直接貼代碼了，只需一個類就可以搞定；

HttpGetImg.h

#ifndef __HttpGetImg__
#define __HttpGetImg__

#include "cocos2d.h"
#include "HttpRequest.h"
#include "HttpClient.h"
USING_NS_CC_EXT;
using namespace std;
USING_NS_CC;

class HttpGetImg : public cocos2d::CCLayer
{
public:
    
    HttpGetImg();
    ~HttpGetImg();
    //獲取網絡圖片，需要地址
    static void GetHttpImg(CCObject* obj, string imgurl,int number);
    
    void onHttpRequestRptImg(cocos2d::extension::CCHttpClient *sender, cocos2d::extension::CCHttpResponse *response);

    //按原來默認頭像比例設置新圖片大小
    static void setImgSize(int oldhead_w,int oldhead_h,CCSprite* sprite);
    
    //創建圖片覆蓋原有圖片
    static void CreateImg(CCSprite* tagSprite,CCSprite* oldSprite,CCTexture2D* texture,int newTag);
private:
    
};

#endif /* HttpGetImg */

HttpGetImg.cpp

#include "HttpGetImg.h"
#include "../DataModel/GlobalInfo.h"
#include "../GameConfig.h"
#include "../Commen/PublicDoFunc.h"
HttpGetImg::HttpGetImg(void)
{
    
}

void HttpGetImg::GetHttpImg(CCObject* obj, string imgurl,int number)
{
    CCHttpRequest* request = new CCHttpRequest();
    // required fields
    request->setUrl(imgurl.c_str());
    request->setRequestType(CCHttpRequest::kHttpGet);
    request->setResponseCallback(obj, httpresponse_selector(HttpGetImg::onHttpRequestRptImg));
    // optional fields
    char thisnumber[10] = "";
    sprintf(thisnumber, "%d",number);
    request->setTag(thisnumber);
    CCHttpClient::getInstance()->send(request);
    request->release();
}

void HttpGetImg::onHttpRequestRptImg(CCHttpClient *sender, CCHttpResponse *response)
{
    
    char c_tag[20]= "";
    sprintf(c_tag, "%s",response->getHttpRequest()->getTag());
    //    CCLog("%s completed", response->getHttpRequest()->getTag());
    string str_tag = c_tag;
    if (!response)
    {
        return;
    }
    // You can get original request type from: response->request->reqType
    if (0 != strlen(response->getHttpRequest()->getTag()))
    {
        //        CCLog("%s completed", response->getHttpRequest()->getTag());
    }
    
    if (!response->isSucceed())
    {
        CCLog("response failed");
        CCLog("error buffer: %s", response->getErrorBuffer());
        return;
    }
    
    vector<char> *buffer = response->getResponseData();
    
    //create image
    CCImage* img = new CCImage;
    img->initWithImageData((unsigned char*)buffer->data(),buffer->size());
    
    //create texture
    CCTexture2D* texture = new CCTexture2D();
    bool isImg = texture->initWithImage(img);
    img->release();
    
　　 //將texture存下來
    texture

    //已下是自己封裝的PublicDoFunc異步調用主線程執行換圖操作的部分，可以自己去封裝
    //SEL_CallFuncN pfnCallback =callfuncN_selector(View_Room::upPlayerHead);
    //CCNode* nd = CCNode::create();
    //buffer->clear();
    //nd->setTag(CCString::create(str_tag)->intValue());
    //PublicDoFunc::toDoFuncN(LAYER_ROOM, pfnCallback,nd);
}

void HttpGetImg::setImgSize(int oldhead_w,int oldhead_h,CCSprite* sprite)
{
    float s_X=oldhead_w/sprite->getContentSize().width;
    float s_Y=oldhead_h/sprite->getContentSize().height;
    sprite->setScaleX(s_X);
    sprite->setScaleY(s_Y);
}

void HttpGetImg::CreateImg(CCSprite* tagSprite,CCSprite* oldSprite,CCTexture2D* texture,int newTag)
{
    int oldw =oldSprite->getContentSize().width;
    int oldh =oldSprite->getContentSize().height;
    if(texture!=NULL)
    {
        CCSprite* sprite = CCSprite::createWithTexture(texture);
        //按原比例設置
        setImgSize(oldw,oldh,sprite);
        sprite->setPosition(oldSprite->getPosition());
        tagSprite->addChild(sprite,1,newTag);
        texture->release();
    }
}


HttpGetImg::~HttpGetImg(void)
{
    
}

 

代碼非常簡潔簡單，先通過：

GetHttpImg(CCObject* obj, string imgurl,int number);

獲取到texture，然后把texture存起來，在自己要展示的頁面去調用：

CreateImg(CCSprite* tagSprite,CCSprite* oldSprite,CCTexture2D* texture,int newTag)

第一個參數是要展示的父級sprite,第二個是默認頭像圖片（如果沒有下載成功網絡圖片，顯示替代圖片）,第三個是緩存的texture；

 

效果圖：

 

結束，祝大家新年快樂；

ps:群號（41131516）