GTKMM应用程序:GDK键按信号未触发

Question

i已复制(但有一些修改(键盘事件的GTKMM教程中的示例。(链接(

https://developer.gnome.org/gtkmm-tutorial/stable/sec-keyboardevents-everevents-overview.html.en#keyboardevents-simple-example

这是我的代码：

#include <gtkmm/application.h>
#include <gtkmm/window.h>
#include <gtkmm/textview.h>
#include <iostream>
class MainWindow
{
    public:
    MainWindow()
    {
        _window_.set_default_size(600, 400);
        _window_.add(_textview_);
        Glib::RefPtr<Gtk::TextBuffer> textbuffer_rp{_textview_.get_buffer()};
        textbuffer_rp->set_text("some text here");
        _textview_.set_monospace();
        _window_.add_events(Gdk::KEY_PRESS_MASK);
        _window_.show_all_children();
    }
    Gtk::Window &get_window()
    {
        return _window_;
    }
    protected:
    bool on_key_press_event(GdkEventKey* event)
    {
        std::cout << "some keypress event" << std::endl; 
        if
        (
            (event->keyval == GDK_KEY_H) &&
            ((event->state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK) == GDK_CONTROL_MASK))
        )
        {
            std::cout << "Hello world!" << std::endl;
        }
        if
        (
            (event->keyval == GDK_KEY_C) &&
            ((event->state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK) == GDK_CONTROL_MASK))
        )
        {
            signal_textview_CTRL_C();
        }
        else if
        ( 
            (event->keyval == GDK_KEY_V) &&
            ((event->state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK) == GDK_CONTROL_MASK))
        )
        {
            signal_textview_CTRL_V();
        }
        else
        {
            std::cout << "unhandled key" << std::endl;
        }
        return true;
    }
    void signal_textview_CTRL_C()
    {
        _text_register_0_ = "some text gets put here";
    }
    void signal_textview_CTRL_V()
    {
        Glib::RefPtr<Gtk::TextBuffer> textbuffer_rp{_textview_.get_buffer()};
        textbuffer_rp->set_text(_text_register_0_);
    }
    private:
    Gtk::Window _window_;
    Gtk::TextView _textview_;
    Glib::ustring _text_register_0_;
};
int main(int argc, char *argv[])
{
    auto app = Gtk::Application::create(argc, argv, "org.gtkmm.examples.base");
    MainWindow mainwindow;
    return app->run(mainwindow.get_window());
}

但是它不起作用 - 当我按下键序列ctrl-c，ctrl-v，ctrl-h。

我认为我已经从代码中剥离了所有无关紧要的东西，所以这应该是工作的MWE。

Answer 1

1. 首先将处理程序连接。

   _window_.signal_key_press_event().connect(sigc::mem_fun(*this, &MainWindow::on_key_press_event), false);
   

2. 返回false到_textview_获取键。

3. 您的情况是矛盾的。

   GDK_KEY_H是Shift H的密钥。然后您检查(event->state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK | GDK_MOD1_MASK) == GDK_CONTROL_MASK)。您询问state(我们知道与GDK_SHIFT_MASK一起(是否仅为GDK_CONTROL_MASK。

代码：

#include <gtkmm/application.h>
#include <gtkmm/window.h>
#include <gtkmm/textview.h>
#include <iostream>
class MainWindow
{
public:
    MainWindow()
    {
        _window_.set_default_size(600, 400);
        _window_.add(_textview_);
        Glib::RefPtr<Gtk::TextBuffer> textbuffer_rp{_textview_.get_buffer()};
        textbuffer_rp->set_text("some text here");
        _textview_.set_monospace();
        _window_.add_events(Gdk::KEY_PRESS_MASK);
        _window_.signal_key_press_event().connect(sigc::mem_fun(*this, &MainWindow::on_key_press_event), false);
        _window_.show_all_children();
    }
    Gtk::Window &get_window()
    {
        return _window_;
    }
protected:
    bool on_key_press_event(GdkEventKey* event)
    {
        std::cout << "some keypress event " << std::hex<<event->keyval<<" "<<std::hex<<event->state<<std::endl; 
        if
            (
             (event->keyval == GDK_KEY_h) &&
             (event->state & GDK_CONTROL_MASK)
             )
        {
            std::cout << "Hello world!" << std::endl;
            return true;
        }
        if
            (
             (event->keyval == GDK_KEY_c) &&
             (event->state & GDK_CONTROL_MASK)
             )
        {
            std::cout<<"ctrl c"<<std::endl;
            signal_textview_CTRL_C();
            return true;
        }
        else if
            ( 
             (event->keyval == GDK_KEY_v) &&
             (event->state & GDK_CONTROL_MASK)
              )
        {
            std::cout<<"ctrl v"<<std::endl;
            signal_textview_CTRL_V();
            return true;
        }
        else
        {
            std::cout << "unhandled key" << std::endl;
        }
        return false;
    }
    void signal_textview_CTRL_C()
    {
        _text_register_0_ = "some text gets put here";
    }
    void signal_textview_CTRL_V()
    {
        Glib::RefPtr<Gtk::TextBuffer> textbuffer_rp{_textview_.get_buffer()};
        textbuffer_rp->set_text(_text_register_0_);
    }
private:
    Gtk::Window _window_;
    Gtk::TextView _textview_;
    Glib::ustring _text_register_0_;
};
int main(int argc, char *argv[])
{
    auto app = Gtk::Application::create(argc, argv, "org.gtkmm.examples.base");
    MainWindow mainwindow;
    return app->run(mainwindow.get_window());
}