如何創建對象並在 Objective-C 中使用它？

Question

我正在為我的游戲使用 Buildbox。 我實施了自定義激勵廣告。 問題是當獎勵視頻打開時游戲音樂會繼續。 我想在觀看視頻后靜音和取消靜音。

我知道 Java，但我不擅長 Objective-C 和 Cocos2dx。

我的AudioEngine.h類：在 libs/cocos2dx/include/audio/include/ 下

/****************************************************************************
 Copyright (c) 2014-2015 Chukong Technologies Inc.

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 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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#include "platform/CCPlatformConfig.h"

#ifndef __AUDIO_ENGINE_H_
#define __AUDIO_ENGINE_H_

#include <functional>
#include <list>
#include <string>
#include <unordered_map>

#include "platform/CCPlatformMacros.h"
#include "audio/include/Export.h"

#ifdef ERROR
#undef ERROR
#endif // ERROR

/**
 * @addtogroup audio
 * @{
 */

NS_CC_BEGIN
    namespace experimental{

/**
 * @class AudioProfile
 *
 * @brief
 * @js NA
 */
class CC_DLL AudioProfile
{
public:
    //Profile name can't be empty.
    std::string name;
    //The maximum number of simultaneous audio instance.
    unsigned int maxInstances;

    /* Minimum delay in between sounds */
    double minDelay;

    /**
     * Default constructor
     *
     * @lua new
     */
    AudioProfile()
    : maxInstances(0)
    , minDelay(0.0)
    {

    }
};

class AudioEngineImpl;

/**
 * @class AudioEngine
 *
 * @brief Offers a interface to play audio.
 *
 * @note Make sure to call AudioEngine::end() when the audio engine is not needed anymore to release resources.
 * @js NA
 */

class CC_DLL AudioEngine
{
public:
    /** AudioState enum,all possible states of an audio instance.*/
    enum class AudioState
    {
        ERROR  = -1,
        INITIALZING,
        PLAYING,
        PAUSED
    };

    static const int INVALID_AUDIO_ID;

    static const float TIME_UNKNOWN;

    static bool lazyInit();

    /**
     * Release objects relating to AudioEngine.
     *
     * @warning It must be called before the application exit.
     * @lua endToLua
     */
    static void end();

    /**  
     * Gets the default profile of audio instances.
     *
     * @return The default profile of audio instances.
     */
    static AudioProfile* getDefaultProfile();

    /** 
     * Play 2d sound.
     *
     * @param filePath The path of an audio file.
     * @param loop Whether audio instance loop or not.
     * @param volume Volume value (range from 0.0 to 1.0).
     * @param profile A profile for audio instance. When profile is not specified, default profile will be used.
     * @return An audio ID. It allows you to dynamically change the behavior of an audio instance on the fly.
     *
     * @see `AudioProfile`
     */
    static int play2d(const std::string& filePath, bool loop = false, float volume = 1.0f, const AudioProfile *profile = nullptr);

    /** 
     * Sets whether an audio instance loop or not.
     *
     * @param audioID An audioID returned by the play2d function.
     * @param loop Whether audio instance loop or not.
     */
    static void setLoop(int audioID, bool loop);

    /** 
     * Checks whether an audio instance is loop.
     *
     * @param audioID An audioID returned by the play2d function.
     * @return Whether or not an audio instance is loop.
     */
    static bool isLoop(int audioID);

    /** 
     * Sets volume for an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     * @param volume Volume value (range from 0.0 to 1.0).
     */
    static void setVolume(int audioID, float volume);

    /** 
     * Gets the volume value of an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     * @return Volume value (range from 0.0 to 1.0).
     */
    static float getVolume(int audioID);

    /** 
     * Pause an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     */
    static void pause(int audioID);

    /** Pause all playing audio instances. */
    static void pauseAll();

    /** 
     * Resume an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     */
    static void resume(int audioID);

    /** Resume all suspended audio instances. */
    static void resumeAll();

    /** 
     * Stop an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     */
    static void stop(int audioID);

    /** Stop all audio instances. */
    static void stopAll();

    /**
     * Sets the current playback position of an audio instance.
     *
     * @param audioID   An audioID returned by the play2d function.
     * @param sec       The offset in seconds from the start to seek to.
     * @return 
     */
    static bool setCurrentTime(int audioID, float sec);

    /** 
     * Gets the current playback position of an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     * @return The current playback position of an audio instance.
     */
    static float getCurrentTime(int audioID);

    /** 
     * Gets the duration of an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     * @return The duration of an audio instance.
     */
    static float getDuration(int audioID);

    /** 
     * Returns the state of an audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     * @return The status of an audio instance.
     */
    static AudioState getState(int audioID);

    /** 
     * Register a callback to be invoked when an audio instance has completed playing.
     *
     * @param audioID An audioID returned by the play2d function.
     * @param callback
     */
    static void setFinishCallback(int audioID, const std::function<void(int,const std::string&)>& callback);

    /**
     * Gets the maximum number of simultaneous audio instance of AudioEngine.
     */
    static int getMaxAudioInstance() {return _maxInstances;}

    /**
     * Sets the maximum number of simultaneous audio instance for AudioEngine.
     *
     * @param maxInstances The maximum number of simultaneous audio instance.
     */
    static bool setMaxAudioInstance(int maxInstances);

    /** 
     * Uncache the audio data from internal buffer.
     * AudioEngine cache audio data on ios,mac, and win32 platform.
     *
     * @warning This can lead to stop related audio first.
     * @param filePath Audio file path.
     */
    static void uncache(const std::string& filePath);

    /** 
     * Uncache all audio data from internal buffer.
     *
     * @warning All audio will be stopped first.
     */
    static void uncacheAll();

    /**  
     * Gets the audio profile by id of audio instance.
     *
     * @param audioID An audioID returned by the play2d function.
     * @return The audio profile.
     */
    static AudioProfile* getProfile(int audioID);

    /**  
     * Gets an audio profile by name.
     *
     * @param profileName A name of audio profile.
     * @return The audio profile.
     */
    static AudioProfile* getProfile(const std::string &profileName);

    /**
     * Preload audio file.
     * @param filePath The file path of an audio.
     */
    static void preload(const std::string& filePath) { preload(filePath, nullptr); }

    /**
     * Preload audio file.
     * @param filePath The file path of an audio.
     * @param callback A callback which will be called after loading is finished.
     */
    static void preload(const std::string& filePath, std::function<void(bool isSuccess)> callback);

protected:
    static void addTask(const std::function<void()>& task);
    static void remove(int audioID);

    struct ProfileHelper
    {
        AudioProfile profile;

        std::list<int> audioIDs;

        double lastPlayTime;

        ProfileHelper()
            : lastPlayTime(0.0)
        {

        }
    };

    struct AudioInfo
    {
        const std::string* filePath;
        ProfileHelper* profileHelper;

        float volume;
        bool loop;
        float duration;
        AudioState state;

        AudioInfo()
            : profileHelper(nullptr)
            , duration(TIME_UNKNOWN)
            , state(AudioState::INITIALZING)
        {

        }
    };

    //audioID,audioAttribute
    static std::unordered_map<int, AudioInfo> _audioIDInfoMap;

    //audio file path,audio IDs
    static std::unordered_map<std::string,std::list<int>> _audioPathIDMap;

    //profileName,ProfileHelper
    static std::unordered_map<std::string, ProfileHelper> _audioPathProfileHelperMap;

    static unsigned int _maxInstances;

    static ProfileHelper* _defaultProfileHelper;

    static AudioEngineImpl* _audioEngineImpl;

    class AudioEngineThreadPool;
    static AudioEngineThreadPool* s_threadPool;

    friend class AudioEngineImpl;
};

}
NS_CC_END

// end group
/// @}

#endif // __AUDIO_ENGINE_H_

AdIntegrator 類。

    #import "AdIntegrator.h"
    #import <GoogleMobileAds/GoogleMobileAds.h>
    #import <UIKit/UIKit.h>
    #import "AppDelegate.h"
    #include "ads/PTAdController.h"
    #include "cocos2dx/include/audio/include/AudioEngine.h"



   @implementation AdIntegrator

    NSString *rewardedAdUnitId =@"ca-app-pub-0000000000/00000000";

    //Java equality : AudioEngine audio = new AudioEngine(); 


    + (id)shared{
        static AdIntegrator* integrator = nil;
        @synchronized(self){
            if(integrator == nil){
                integrator = [[self alloc] init];
            }
        }
        return integrator;
    }

    #pragma mark Core Methods

    - (void)initAds{
//Java Equality: audio.pauseAll();
        NSLog(@"[Ads] initialization");
        [GADRewardBasedVideoAd sharedInstance].delegate = self;
        [[GADRewardBasedVideoAd sharedInstance] loadRequest:[GADRequest request]
                                               withAdUnitID:rewardedAdUnitId];
    }



    #pragma mark Integration

    @end

如何在 Objective-C 中創建對象並使用它的方法？

Java 平等：

AudioEngine audio = new AudioEngine(); 

audio.pauseAll();

如何在 Objective-C 中執行此代碼？

Answer 1

嘗試使用以下代碼對其進行初始化。

AudioEngine *audio = [[AudioEngine alloc] init];

您可以使用以下代碼來調用其方法。

[audio pauseAll];

如果你有一些像 audio.abc.pausAll 這樣的代碼，那么你可以通過簡單地添加 [] 來調用它。

例如

[[audio abc] pauseAll];

Answer 2

AudioEngine是一個 C++ 類。 您將從 Obj-C 調用 C++。 特別是， AudioEngine的方法是靜態函數，因此沒有要創建的“對象”。

您應該暫停和恢復，而不是靜音和取消靜音，因為靜音會繼續播放，只需將音量設置為 0。此外，根據您列出的AudioEngine標頭中的功能，暫停更容易。 音量控制需要知道audioID ，這需要一些跟蹤以確保所有播放的音頻靜音/取消靜音。

當您想暫停時，只需調用：

experimental::AudioEngine::pauseAll();

要恢復，只需調用：

experimental::AudioEngine::resumeAll();

僅供參考，您可能還需要使用cocos2d命名空間。 這意味着experimental將更改為cocos2d::experimental 。

另一個警告是您的 Obj-C 代碼必須編譯為 Objective-C++ 源代碼。

有兩種方法可以做到這一點。

1. 源文件使用.mm擴展名。
2. 在 Xcode 的 File Inspector 中設置的文件類型明確設置為Objective-C++ Source 。 .m文件將被列為Objective-C Source 。 為此，請在 Project Navigator 中選擇文件，然后在菜單中選擇 View:Inspectors:Show File Inspector。 文件檢查器（如果尚未出現）將顯示在最右側。

Answer 3

我解決了我的問題。 我可以使用以下方法在 AdIntegrator 類中靜音和取消靜音：

這將使所有聲音靜音。

PTAdController::shared()->setMusic(false);

這將取消所有聲音的靜音。

PTAdController::shared()->setMusic(true);