Cocos2dx中在场景中弹出模态层时按钮的处理方法

在Cocos2dx游戏开发中经常会遇到在场景中弹出模态层，并在弹出层中添加按钮的情况。通常做法是在弹出层中添加一个背景颜色遮罩，然后在弹出层将触摸事件吞噬掉，使得在弹出层里处理触摸事件，判断触摸点是否在Button上，以此处理按钮事件。但是这样会出现按钮的显示不正常的问题，即按钮在点击之后会显示禁用的效果，解决防范是创建按钮的时候传入三个图片参数，最后两个参数是按钮点击和禁用时的图片，将他们设置为一样就行了。下面贴出具体代码，并对代码测试。

PopupLayer.h

#ifndef __POPUP_LAYER_H__#define __POPUP_LAYER_H__#include "cocos2d.h"#include "ui/UIButton.h"typedef enum tagButtonResult{ButtonResult_OK = 0} ButtonResult;typedef std::function<void(cocos2d::Ref*, ButtonResult)> ButtonTouchedCallback;class PopupLayer : public cocos2d::Layer{public:    // Here's a difference. Method 'init' in cocos2d-x returns bool, instead of returning 'id' in cocos2d-iphone    virtual bool init() override;// 触摸事件virtual bool onTouchBegan(cocos2d::Touch *touch, cocos2d::Event *unused_event);virtual void onTouchMoved(cocos2d::Touch *touch, cocos2d::Event *unused_event);virtual void onTouchEnded(cocos2d::Touch *touch, cocos2d::Event *unused_event);virtual void onTouchCancelled(cocos2d::Touch *touch, cocos2d::Event *unused_event);// implement the "static create()" method manuallyCREATE_FUNC(PopupLayer);public://设置按钮回调函数void SetCallBackFunc(ButtonTouchedCallback callfunc);private://销毁layer并调用回调函数void DestroySelf(cocos2d::Ref* sender, ButtonResult result);//按钮回调函数void buttonCallback(cocos2d::Ref* sender, cocos2d::ui::Widget::TouchEventType event);protected:cocos2d::EventListenerTouchOneByOne*m_touchListener;//触屏事件监听器ButtonTouchedCallbackm_callback;//按钮回调函数};#endif // __POPUP_LAYER_H__

PopupLayer.cpp

#include "PopupLayer.h"USING_NS_CC;using namespace ui;const int TAG_BUTTON = 1;// on "init" you need to initialize your instancebool PopupLayer::init(){if ( !Layer::init() ){return false;}m_callback = nullptr;//获取游戏区域Size visibleSize = Director::getInstance()->getVisibleSize();Vec2 origin = Director::getInstance()->getVisibleOrigin();//添加透明遮罩auto mask = LayerColor::create(Color4B(0, 0, 0, 128), visibleSize.width, visibleSize.height);this->addChild(mask);//由于PopupLayer将触摸事件吞噬了，导致在判断点击事件的时候//使用了触摸点坐标是否在按钮是区域内的方式，这样Button的//setBright方法会使得点击按钮的时候显示Disable状态的图片，//因此将按钮的点击和禁用图片设置为一样，来解决这个问题。auto button = Button::create("test.png", "test_effect.png", "test_effect.png");button->setScale9Enabled(true);button->setTitleText("test button");button->setTitleFontSize(40);button->setContentSize(Size(visibleSize.width / 2, visibleSize.width / 4));button->setPosition(Vec2(origin.x + visibleSize.width / 2,origin.y + visibleSize.height / 2));button->addTouchEventListener(CC_CALLBACK_2(PopupLayer::buttonCallback, this));this->addChild(button, 0, TAG_BUTTON);//触摸屏事件监听m_touchListener = EventListenerTouchOneByOne::create();m_touchListener->onTouchBegan = CC_CALLBACK_2(PopupLayer::onTouchBegan, this);m_touchListener->onTouchMoved = CC_CALLBACK_2(PopupLayer::onTouchMoved, this);m_touchListener->onTouchEnded = CC_CALLBACK_2(PopupLayer::onTouchEnded, this);m_touchListener->onTouchCancelled = CC_CALLBACK_2(PopupLayer::onTouchCancelled, this);m_touchListener->setSwallowTouches(true);this->getEventDispatcher()->addEventListenerWithFixedPriority(m_touchListener, -128);return true;}void PopupLayer::SetCallBackFunc(ButtonTouchedCallback callfunc){this->m_callback = callfunc;}//销毁layer并调用回调函数void PopupLayer::DestroySelf(cocos2d::Ref* sender, ButtonResult result){this->getEventDispatcher()->removeEventListener(m_touchListener);m_callback(sender, result);this->removeFromParentAndCleanup(true);}// 触摸开始事件bool PopupLayer::onTouchBegan(cocos2d::Touch *touch, cocos2d::Event *unused_event){auto button = (Button*)this->getChildByTag(TAG_BUTTON);if (button != nullptr){const Size& size = button->getContentSize();const Vec2& pos = button->getPosition();Rect rect = Rect(pos.x - size.width / 2, pos.y - size.height / 2, size.width, size.height);auto touchLocation = touch->getLocation();if (rect.containsPoint(touchLocation)){button->setBright(false);button->onTouchBegan(touch, unused_event);}}return true;}// 触摸滑动void PopupLayer::onTouchMoved(cocos2d::Touch *touch, cocos2d::Event *unused_event){auto button = (Button*)this->getChildByTag(TAG_BUTTON);if (button != nullptr){const Size& size = button->getContentSize();const Vec2& pos = button->getPosition();Rect rect = Rect(pos.x - size.width / 2, pos.y - size.height / 2, size.width, size.height);auto touchLocation = touch->getLocation();if (rect.containsPoint(touchLocation)){button->onTouchMoved(touch, unused_event);}else{button->setBright(true);}}}// 触摸结束事件void PopupLayer::onTouchEnded(cocos2d::Touch *touch, cocos2d::Event *unused_event){auto button = (Button*)this->getChildByTag(TAG_BUTTON);if (button != nullptr){const Size& size = button->getContentSize();const Vec2& pos = button->getPosition();Rect rect = Rect(pos.x - size.width / 2, pos.y - size.height / 2, size.width, size.height);auto touchLocation = touch->getLocation();button->setBright(true);if (rect.containsPoint(touchLocation)){button->onTouchEnded(touch, unused_event);}}}// 触摸取消事件void PopupLayer::onTouchCancelled(cocos2d::Touch *touch, cocos2d::Event *unused_event){auto button = (Button*)this->getChildByTag(TAG_BUTTON);if (button != nullptr){const Size& size = button->getContentSize();const Vec2& pos = button->getPosition();Rect rect = Rect(pos.x - size.width / 2, pos.y - size.height / 2, size.width, size.height);auto touchLocation = touch->getLocation();button->setBright(true);if (rect.containsPoint(touchLocation)){button->onTouchCancelled(touch, unused_event);}}}void PopupLayer::buttonCallback(cocos2d::Ref* sender, cocos2d::ui::Widget::TouchEventType event){if (Widget::TouchEventType::CANCELED == event){auto button = (Button*)sender;if (button != nullptr){if (TAG_BUTTON == button->getTag()){DestroySelf(sender, ButtonResult::ButtonResult_OK);}}}}

HelloWorldScene.h

#ifndef __HELLOWORLD_SCENE_H__#define __HELLOWORLD_SCENE_H__#include "cocos2d.h"#include "PopupLayer.h"class HelloWorld : public cocos2d::Scene{public:    static cocos2d::Scene* createScene();    virtual bool init();        // a selector callback    void menuCloseCallback(cocos2d::Ref* pSender);        // implement the "static create()" method manually    CREATE_FUNC(HelloWorld);public://弹出框按钮事件void buttonPopupCallback(cocos2d::Ref* sender, ButtonResult result);};#endif // __HELLOWORLD_SCENE_H__

HelloWorldScene.cpp

#include "HelloWorldScene.h"USING_NS_CC;Scene* HelloWorld::createScene(){    return HelloWorld::create();}// on "init" you need to initialize your instancebool HelloWorld::init(){    //////////////////////////////    // 1. super init first    if ( !Scene::init() )    {        return false;    }        auto visibleSize = Director::getInstance()->getVisibleSize();    Vec2 origin = Director::getInstance()->getVisibleOrigin();    /////////////////////////////    // 2. add a menu item with "X" image, which is clicked to quit the program    //    you may modify it.    // add a "close" icon to exit the progress. it's an autorelease object    auto closeItem = MenuItemImage::create(                                           "CloseNormal.png",                                           "CloseSelected.png",                                           CC_CALLBACK_1(HelloWorld::menuCloseCallback, this));        closeItem->setPosition(Vec2(origin.x + visibleSize.width - closeItem->getContentSize().width/2 ,                                origin.y + closeItem->getContentSize().height/2));    // create menu, it's an autorelease object    auto menu = Menu::create(closeItem, NULL);    menu->setPosition(Vec2::ZERO);    this->addChild(menu, 1);    /////////////////////////////    // 3. add your codes below...    // add a label shows "Hello World"    // create and initialize a label        auto label = Label::createWithTTF("Hello World", "fonts/Marker Felt.ttf", 24);        // position the label on the center of the screen    label->setPosition(Vec2(origin.x + visibleSize.width/2,                            origin.y + visibleSize.height - label->getContentSize().height));    // add the label as a child to this layer    this->addChild(label, 1);    // add "HelloWorld" splash screen"    auto sprite = Sprite::create("HelloWorld.png");    // position the sprite on the center of the screen    sprite->setPosition(Vec2(visibleSize.width/2 + origin.x, visibleSize.height/2 + origin.y));    // add the sprite as a child to this layer    this->addChild(sprite, 0);//添加弹出模态层auto login = PopupLayer::create();login->SetCallBackFunc(CC_CALLBACK_2(HelloWorld::buttonPopupCallback, this));this->addChild(login, 10);        return true;}void HelloWorld::menuCloseCallback(Ref* pSender){    //Close the cocos2d-x game scene and quit the application    Director::getInstance()->end();    #if (CC_TARGET_PLATFORM == CC_PLATFORM_IOS)    exit(0);#endif        /*To navigate back to native iOS screen(if present) without quitting the application  ,do not use Director::getInstance()->end() and exit(0) as given above,instead trigger a custom event created in RootViewController.mm as below*/        //EventCustom customEndEvent("game_scene_close_event");    //_eventDispatcher->dispatchEvent(&customEndEvent);}void HelloWorld::buttonPopupCallback(cocos2d::Ref* sender, ButtonResult result){switch (result){case ButtonResult::ButtonResult_OK:Director::getInstance()->end();break;default:break;}}