如何在数组中初始化此类?

How can I initialise this class in an array?

本文关键字:初始化 数组      更新时间:2023-10-16

我正在尝试制作一个类文件播放器Gui的数组,当我尝试在构造函数中初始化它时,它不会让我这样做

class MainComponent   : public Component,
public MenuBarModel
{
public:
//==============================================================================
/** Constructor */
MainComponent (Audio& audio_);
/** Destructor */
~MainComponent();
void resized() override;
//MenuBarEnums/Callbacks========================================================
enum Menus
{
FileMenu=0,
NumMenus
};
enum FileMenuItems
{
AudioPrefs = 1,
NumFileItems
};
StringArray getMenuBarNames() override;
PopupMenu getMenuForIndex (int topLevelMenuIndex, const String& menuName) override;
void menuItemSelected (int menuItemID, int topLevelMenuIndex) override;
private:
Audio& audio;
FilePlayerGui filePlayerGui[2] {audio.getFilePlayer(0), audio.getFilePlayer(1)};

//==============================================================================
JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MainComponent)
};

filePlayerGui 出现此错误"复制类型为'FilePlayerGui'的数组元素调用已删除的构造函数"。 我尝试在下面.cpp文件中初始化它,但它告诉我需要一个数组初始化器

MainComponent::MainComponent (Audio& audio_) : audio (audio_)
{

setSize (500, 400);
addAndMakeVisible(filePlayerGui[0]);
addAndMakeVisible(filePlayerGui[1]);
}
MainComponent::~MainComponent()
{
}
void MainComponent::resized()
{
filePlayerGui[0].setBounds (0, 0, getWidth(), 40);
}
//MenuBarCallbacks==============================================================
StringArray MainComponent::getMenuBarNames()
{
const char* const names[] = { "File", 0 };
return StringArray (names);
}
PopupMenu MainComponent::getMenuForIndex (int topLevelMenuIndex, const String& menuName)
{
PopupMenu menu;
if (topLevelMenuIndex == 0)
menu.addItem(AudioPrefs, "Audio Prefrences", true, false);
return menu;
}
void MainComponent::menuItemSelected (int menuItemID, int topLevelMenuIndex)
{
if (topLevelMenuIndex == FileMenu)
{
if (menuItemID == AudioPrefs)
{
AudioDeviceSelectorComponent audioSettingsComp (audio.getAudioDeviceManager(),
0, 2, 2, 2, true, true, true, false);
audioSettingsComp.setSize (450, 350);
DialogWindow::showModalDialog ("Audio Settings",
&audioSettingsComp, this, Colours::lightgrey, true);
}
}
}

复制类型为FilePlayerGui的数组元素会调用已删除的构造函数

意味着这一行在FilePlayerGui声明中的某个变体:

FilePlayerGui(const FilePlayerGui&) = delete

这意味着无法复制FilePlayerGui:https://en.cppreference.com/w/cpp/language/copy_constructor#Deleted_implicitly-declared_copy_constructor

有一些解决方法,但你正在回避FilePlayerGui的作者对课程的意图。所以正确的答案应该到此为止。FilePlayerGui的任何使用都应通过类audio成员完成,使用:audio.getFilePlayer(0)audio.getFilePlayer(1)。(如果这是MainComponent的唯一成员,则很可能MainComponent应该被淘汰。


如果你想知道如何做坏事,我会在任何代码审查中拒绝,你可以创建filePointerGui为:

  1. FilePointerGui* filePointerGui[2],将初始化为:
MainComponent::MainComponent(Audio& audio_) : audio(audio_), filePointerGui({ &audio.getFilePlayer(0), &audio.getFilePlayer(1) })

       访问将按以下方式执行:

*filePointerGui[0]

       现场示例

  1. reference_wrapper<FilePointerGui> filePointerGui[2]初始化为:
MainComponent::MainComponent(Audio& audio_) : audio(audio_), filePointerGui({ audio.getFilePlayer(0), audio.getFilePlayer(1) })

       访问将按以下方式执行:

filePointerGui[0].get()

       现场示例

可能值得再次强调这是糟糕的代码,因为它试图超越语言并围绕类设计的意图工作。但这是 c++,所以你可以做到。