什么是`HelloWorld：public Gtk :: Window'是什么意思？ [英] What does `class HelloWorld : public Gtk::Window` mean?

问题描述

我正在关注GtkHello World教程在这里，我遇到了一个类声明我从来没有见过的一行（我只是学习编程几个月了），我想知道是否有人可以给我解释。该行是

I'm following the Gtk "Hello World" tutorial found here, and I've come across a line in a class declaration I've never seen before (I've only been learning to program for a few months now), and I was wondering if someone could please explain it to me. The line is the

class HelloWorld : public Gtk::Window

我知道类HelloWorld 在做什么，但我从来没有见过 public Gtk :: Window 之前。提供完整的头文件以供参考。

I know what class HelloWorld is doing, but I've never seen the public Gtk::Window before. The full header file is provided for reference.

#ifndef GTKMM_EXAMPLE_HELLOWORLD_H
#define GTKMM_EXAMPLE_HELLOWORLD_H

#include <gtkmm/button.h>
#include <gtkmm/window.h>

class HelloWorld : public Gtk::Window
{

public:
  HelloWorld();
  virtual ~HelloWorld();

protected:
  //Signal handlers:
  void on_button_clicked();

  //Member widgets:
  Gtk::Button m_button;
};

#endif // GTKMM_EXAMPLE_HELLOWORLD_H

推荐答案

这意味着 HelloWorld 是从 Gtk :: Window 派生的，因此它继承了它的行为。

It means that HelloWorld is derived from Gtk::Window, so it inherits its behaviour.

HelloWorld 表示一个Gtk窗口，所以它是很自然的从Gtk的窗口类派生。它的构造函数可能会向窗口添加一个按钮（实际的窗口是由父类构造函数创建的，当创建一个 HelloWorld 的新实例时会自动调用...）和

HelloWorld represents a Gtk window, so it is just natural to have it derive from the Gtk's window class. It's constructor will probably add a button to the window (the actual window is created by the parent class constructor, which is invoked automatically when a new instance of HelloWorld is created …) and connect a signal handler (on_button_clicked) to the window.

您可以调用的所有
的方法通过 HelloWorld 的实例。反过来， HelloWorld 可以覆盖 Gtk :: Window 的虚方法来更改其行为。

You can call all of Gtk::Window's methods through an instance of HelloWorld. In turn, HelloWorld can override virtual methods of Gtk::Window to change its behaviour.

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