cocos2d-x ScrollView、TableView

转自：http://codingnow.cn/cocos2d-x/1024.html

在游戏和应用中经常要实现左右滑动展示游戏帮助、以列表显示内容的UI效果，就像android中的Gallery和ListView。本文通过CCScrollView和CCTableView分别来实现这两个效果，基于cocos2d-x 2.0.4版本。
首先来简单了解一下这两个东东，CCScrollView本身是一个CCLayer，而CCTableView是CCScrollView的子类，这是引擎已经帮我们封装好了的，CCTableView可以设置成横向和纵向，用它可以实现类似于Gallery和ListView的效果。
1. 首先实现游戏帮助界面
(1) 创建头文件GalleryLayer.h

#ifndef GALLERY_LAYER_H

#define GALLERY_LAYER_H

 

#include "cocos2d.h"

#include "SimpleAudioEngine.h"

#include "cocos-ext.h"

 

USING_NS_CC;

USING_NS_CC_EXT;

 

class GalleryLayer : public cocos2d::CCLayer ,public CCScrollViewDelegate

{

public:

    virtual bool init();  

 

    void menuCloseCallback(CCObject* pSender);

 

    CREATE_FUNC(GalleryLayer);

 

public:

    //scrollview滚动的时候会调用

    void scrollViewDidScroll(CCScrollView* view);

    //scrollview缩放的时候会调用

    void scrollViewDidZoom(CCScrollView* view);

 

    virtual void onEnter();

    virtual void onExit();

 

    virtual bool ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent);

    virtual void ccTouchMoved(CCTouch *pTouch, CCEvent *pEvent);

    virtual void ccTouchEnded(CCTouch *pTouch, CCEvent *pEvent);

    virtual void ccTouchCancelled(CCTouch *pTouch, CCEvent *pEvent);

 

private:

    //根据手势滑动的距离和方向滚动图层

     void adjustScrollView(float offset);

     CCScrollView *m_pScrollView;

     CCPoint m_touchPoint;

     int m_nCurPage;

};

 

#endif

类GalleryLayer继承了CCScrollViewDelegate，实现了它的两个纯虚函数，主要是为了当scrollview滚动和缩放时回调这两函数，这样我们就可以在这两函数中做相关操作了。

(2) 看源文件GalleryLayer.cpp

#include "GalleryLayer.h"

#include "ListViewLayer.h"

 

using namespace cocos2d;

using namespace cocos2d::extension;

 

bool GalleryLayer::init()

{

    bool bRet = false;

    do

    {

       CC_BREAK_IF( !CCLayer::init() );

 

       m_nCurPage = 1;

       CCSize visibleSize = CCDirector::sharedDirector()->getVisibleSize();

       CCPoint origin = CCDirector::sharedDirector()->getVisibleOrigin();

 

       CCLayer *pLayer = CCLayer::create();

       char helpstr[30] = {0};

       for (int i = 1; i <= 3; ++ i)

       {

           memset(helpstr, 0, sizeof(helpstr));

           sprintf(helpstr,"bg_%02d.png",i);

           CCSprite *pSprite = CCSprite::create(helpstr);

           pSprite->setPosition(ccp(visibleSize.width * (i-0.5f), visibleSize.height / 2));

           pLayer->addChild(pSprite);

       }

 

       m_pScrollView = CCScrollView::create(CCSizeMake(960, 640), pLayer);

       m_pScrollView->setContentOffset(CCPointZero);

       m_pScrollView->setTouchEnabled(false);

       m_pScrollView->setDelegate(this);

       m_pScrollView->setDirection(kCCScrollViewDirectionHorizontal);

       pLayer->setContentSize(CCSizeMake(960*3, 640));

 

       this->addChild(m_pScrollView);

 

       CCSpriteFrameCache *pCache =  CCSpriteFrameCache::sharedSpriteFrameCache();

 

       pCache->addSpriteFrame(CCSpriteFrame::create("button_normal.png",CCRectMake(0, 0, 64, 64)),"button_normal.png");

       pCache->addSpriteFrame(CCSpriteFrame::create("button_selected.png",CCRectMake(0, 0, 64, 64)),"button_selected.png");

       for (int i = 1; i <= 3; ++ i)

       {

           CCSprite *pPoint = CCSprite::createWithSpriteFrameName("button_normal.png");

           pPoint->setTag(i);

           pPoint->setPosition(ccp( origin.x + (visibleSize.width - 3 * pPoint->getContentSize().width)/2 + pPoint->getContentSize().width * (i-1), origin.y + 30));

           this->addChild(pPoint);

       }

        CCSprite *pPoint = (CCSprite *)this->getChildByTag(1);

        pPoint->setDisplayFrame(pCache->spriteFrameByName("button_selected.png"));

 

        bRet = true;

    }while(0);

 

    return bRet;

 

}

 

void GalleryLayer::menuCloseCallback(CCObject* pSender)

{

 

}

 

void GalleryLayer::scrollViewDidScroll(cocos2d::extension::CCScrollView *view)

{

    CCLOG("scroll");

}

 

void GalleryLayer::scrollViewDidZoom(cocos2d::extension::CCScrollView *view)

{

    CCLOG("zoom");

}

 

void GalleryLayer::onEnter()

{

    CCLayer::onEnter();

    CCDirector::sharedDirector()->getTouchDispatcher()->addTargetedDelegate(this, 1, false);

}

 

void GalleryLayer::onExit()

{

    CCDirector::sharedDirector()->getTouchDispatcher()->removeDelegate(this);

    CCLayer::onExit();

    CCSpriteFrameCache::sharedSpriteFrameCache()->removeUnusedSpriteFrames();

}

 

bool GalleryLayer::ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent)

{

    m_touchPoint = CCDirector::sharedDirector()->convertToGL(pTouch->getLocationInView());

    return true;

}

 

void GalleryLayer::ccTouchMoved(CCTouch *pTouch, CCEvent *pEvent)

{

 

}

 

void GalleryLayer::ccTouchEnded(CCTouch *pTouch, CCEvent *pEvent)

{

    CCPoint endPoint = CCDirector::sharedDirector()->convertToGL(pTouch->getLocationInView());

    float distance = endPoint.x - m_touchPoint.x;

    if(fabs(distance) > 50)

    {

        adjustScrollView(distance);

    }

}

 

void GalleryLayer::ccTouchCancelled(cocos2d::CCTouch *pTouch, cocos2d::CCEvent *pEvent)

{

    CCPoint endPoint = CCDirector::sharedDirector()->convertToGL(pTouch->getLocationInView());

    float distance = endPoint.x - m_touchPoint.x;

    if(fabs(distance) > 50)

    {

        adjustScrollView(distance);

    }

}

 

void GalleryLayer::adjustScrollView(float offset)

{

    CCSize visibleSize = CCDirector::sharedDirector()->getVisibleSize();

    CCPoint origin = CCDirector::sharedDirector()->getVisibleOrigin();

    CCSpriteFrameCache *pCache =  CCSpriteFrameCache::sharedSpriteFrameCache();

    CCSprite *pPoint = (CCSprite *)this->getChildByTag(m_nCurPage);

    pPoint->setDisplayFrame(pCache->spriteFrameByName("button_normal.png"));

    if (offset<0)

    {

        m_nCurPage ++;

    }else

    {

        m_nCurPage --;

    }

 

    if (m_nCurPage <1)

    {

        m_nCurPage = 1;

    }

 

    if(m_nCurPage > 3)

    {

        CCLayer *pLayer = ListViewLayer::create();

        CCScene *pScene = CCScene::create();

        pScene->addChild(pLayer);

        CCDirector::sharedDirector()->replaceScene(pScene);

    }

    else

    {

        pPoint = (CCSprite *)this->getChildByTag(m_nCurPage);

        pPoint->setDisplayFrame(pCache->spriteFrameByName("button_selected.png"));

        CCPoint  adjustPos = ccp(origin.x - visibleSize.width * (m_nCurPage-1), 0);

        m_pScrollView->setContentOffset(adjustPos, true);

    }

}

这里一共有三张图，是从捕鱼达人中拿出来的背景图，当滚完三张图时就跳转到ListViewLayer场景去，上面的代码比较容易懂。
首先创建一个CCLayer，包含三张背景图，设置CCLayer的ContentSize，并设置三张图片的位置
然后设置CCLayer为CCScrollview的内容，并设置CCScrollView的显示区域。
最后根据用户滑动的方向和距离，通过设置scrollview的setContentOffset，滚动视图。
CCScrollview.h文件中封装了一个枚举类型，一共有四个方向，常用横向和纵向，这里使用了横向。

typedef enum {

    kCCScrollViewDirectionNone = -1,

    kCCScrollViewDirectionHorizontal = 0,

    kCCScrollViewDirectionVertical,

    kCCScrollViewDirectionBoth

} CCScrollViewDirection;

下面来看看这部分的效果：

 

2. 现在来实现列表展示(ListView)的效果
（1）创建ListViewLayer.h

#ifndef LISTVIEW_LAYER_H

#define LISTVIEW_LAYER_H

 

#include "cocos2d.h"

#include "cocos-ext.h"

 

class ListViewLayer : public cocos2d::CCLayer, public cocos2d::extension::CCTableViewDataSource, public cocos2d::extension::CCTableViewDelegate

{

public:

    virtual bool init();  

 

    virtual void scrollViewDidScroll(cocos2d::extension::CCScrollView* view);

 

    virtual void scrollViewDidZoom(cocos2d::extension::CCScrollView* view);

 

    //处理触摸事件，可以计算点击的是哪一个子项

    virtual void tableCellTouched(cocos2d::extension::CCTableView* table, cocos2d::extension::CCTableViewCell* cell);

    //每一项的宽度和高度

    virtual cocos2d::CCSize cellSizeForTable(cocos2d::extension::CCTableView *table);

    //生成列表每一项的内容

    virtual cocos2d::extension::CCTableViewCell* tableCellAtIndex(cocos2d::extension::CCTableView *table, unsigned int idx);

    //一共多少项

    virtual unsigned int numberOfCellsInTableView(cocos2d::extension::CCTableView *table);

 

    CREATE_FUNC(ListViewLayer);

};

 

#endif

ListViewLayer继承了CCTableViewDataSource和CCTableViewDelegate。这两个抽象类封装了几个有用的函数，我们在下面的源码中将实现它们。
（2）源文件 ListViewLayer.cpp

#include "ListViewLayer.h"

 

USING_NS_CC;

USING_NS_CC_EXT;

 

bool ListViewLayer::init()

{

    bool bRet = false;

    do

    {

        CC_BREAK_IF( !CCLayer::init() );

 

        CCTableView* pTableView = CCTableView::create(this, CCSizeMake(960, 640));

        pTableView->setDirection(kCCScrollViewDirectionVertical);

        pTableView->setPosition(CCPointZero);

        pTableView->setDelegate(this);

        pTableView->setVerticalFillOrder(kCCTableViewFillTopDown);

        this->addChild(pTableView);

        pTableView->reloadData();

 

        bRet = true;

    }while(0);

 

    return bRet;

}

 

void ListViewLayer::tableCellTouched(CCTableView* table, CCTableViewCell* cell)

{

    CCLog("cell touched at index: %i", cell->getIdx());

}

 

CCSize ListViewLayer::cellSizeForTable(CCTableView *table)

{

    return CCSizeMake(960, 120);

}

 

CCTableViewCell* ListViewLayer::tableCellAtIndex(CCTableView *table, unsigned int idx)

{

    CCString *pString = CCString::createWithFormat("%d", idx);

    CCTableViewCell *pCell = table->dequeueCell();

    if (!pCell) {

        pCell = new CCTableViewCell();

        pCell->autorelease();

        CCSprite *pSprite = CCSprite::create("listitem.png");

        pSprite->setAnchorPoint(CCPointZero);

        pSprite->setPosition(CCPointZero);

        pCell->addChild(pSprite);

 

        CCLabelTTF *pLabel = CCLabelTTF::create(pString->getCString(), "Arial", 20.0);

        pLabel->setPosition(CCPointZero);

        pLabel->setAnchorPoint(CCPointZero);

        pLabel->setTag(123);

        pCell->addChild(pLabel);

    }

    else

    {

        CCLabelTTF *pLabel = (CCLabelTTF*)pCell->getChildByTag(123);

        pLabel->setString(pString->getCString());

    }

 

    return pCell;

}

 

unsigned int ListViewLayer::numberOfCellsInTableView(CCTableView *table)

{

    return 20;

}

 

void ListViewLayer::scrollViewDidScroll(CCScrollView *view)

{

}

 

void ListViewLayer::scrollViewDidZoom(CCScrollView *view)

{

}

首先需要创建CCTableView，设置它的显示区域和显示方向，这里使用了纵向。设置每个子项的宽度和高度，子项的数量以及每个子项对应的内容。每个子项是一个CCTableViewCell，这里进行了优化，复用了子项对象。
下面是效果图：