c++ - 在 JUCE Audio App 中初始化 AudioDeviceManager

Question

我正在尝试在 MainContentComponent 的构造函数中初始化 AudioDeviceManager 的实例：

MainContentComponent(): deviceManager (getSharedAudioDeviceManager())

在哪里

  AudioDeviceManager& getSharedAudioDeviceManager()  
     {  

 if (sharedAudioDeviceManager == nullptr)

    {
        sharedAudioDeviceManager = new AudioDeviceManager();
        sharedAudioDeviceManager->initialise (2, 2, 0, true, String::empty, 0);
    }

    return *sharedAudioDeviceManager;
} 

我的声明是：

AudioDeviceManager& deviceManager; static ScopedPointer<AudioDeviceManager> sharedAudioDeviceManager;

没有编译错误，但我有运行时错误，其中编译器告诉我：

Undefined symbols for architecture x86_64: "MainContentComponent::sharedAudioDeviceManager", referenced from: MainContentComponent::getSharedAudioDeviceManager() in MainComponent.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation)

完全迷失了。帮助！

Answer 1

您需要在类声明之外定义静态成员，如下所示...

ScopedPointer<AudioDeviceManager> MainContentComponent::sharedAudioDeviceManager;

此外，这是一个链接时错误，而不是运行时错误。