GTK自定义RTL复选框如何从标签部件触发CheckButton悬停事件

要实现标签悬停时同步触发复选框的悬停效果，你只需要监听Gtk::EventBox的鼠标进入/离开事件，手动控制复选框的悬停状态即可，具体修改步骤如下：

1. 在MyWindow类的私有方法部分新增两个事件回调声明：

bool on_label_enter(GdkEventCrossing *);
bool on_label_leave(GdkEventCrossing *);

2. 在MyWindow构造函数中，新增这两个事件的信号绑定：

eventbox.signal_enter_notify_event().connect(sigc::mem_fun(*this, &MyWindow::on_label_enter));
eventbox.signal_leave_notify_event().connect(sigc::mem_fun(*this, &MyWindow::on_label_leave));

3. 实现这两个回调函数：

bool MyWindow::on_label_enter(GdkEventCrossing *event)
{
    // 给复选框添加悬停状态标志
    checkbutton.set_state_flags(Gtk::STATE_FLAG_PRELIGHT, false);
    return true;
}

bool MyWindow::on_label_leave(GdkEventCrossing *event)
{
    // 清除复选框的悬停状态标志
    checkbutton.unset_state_flags(Gtk::STATE_FLAG_PRELIGHT);
    return true;
}

修改完成后运行代码，当鼠标悬停在自定义标签上时，复选框就会和原生复选框一样触发悬停高亮效果，符合预期交互逻辑。

完整修改后可运行代码 #

#include <gtkmm.h>

using Gtk::Application;
using Gtk::Button;
using Gtk::CheckButton;
using Gtk::EventBox;
using Gtk::Grid;
using Gtk::Label;
using Gtk::Window;

class MyWindow : public Window {
    Button      button;
    CheckButton checkbutton;
    EventBox    eventbox;
    Grid        grid;
    Label       label;

    bool on_label_clicked(GdkEventButton *);
    bool on_label_enter(GdkEventCrossing *);
    bool on_label_leave(GdkEventCrossing *);
    void arrange_content_layout();
    
public:
    MyWindow();
};

bool MyWindow::on_label_clicked(GdkEventButton *event)
{
    if (event->button == 1 && event->type == GDK_BUTTON_PRESS) {
        checkbutton.set_active(!checkbutton.get_active());
        return true;
    }

    return false;
}

bool MyWindow::on_label_enter(GdkEventCrossing *event)
{
    checkbutton.set_state_flags(Gtk::STATE_FLAG_PRELIGHT, false);
    return true;
}

bool MyWindow::on_label_leave(GdkEventCrossing *event)
{
    checkbutton.unset_state_flags(Gtk::STATE_FLAG_PRELIGHT);
    return true;
}

void MyWindow::arrange_content_layout()
{
    checkbutton.set_margin_start(6);
    
    button.set_margin_top(24);
    grid.child_property_width(button) = 2;
    
    grid.set_margin_top(24);
    grid.set_margin_start(24);
    grid.set_margin_end(24);
    grid.set_margin_bottom(24);
}

MyWindow::MyWindow()
    : button("Click to steal focus")
    , label ("Our custom RTL label")
{
    eventbox.add(label);
    eventbox.signal_button_press_event().connect(sigc::mem_fun(
            *this, &MyWindow::on_label_clicked));
    eventbox.signal_enter_notify_event().connect(sigc::mem_fun(*this, &MyWindow::on_label_enter));
    eventbox.signal_leave_notify_event().connect(sigc::mem_fun(*this, &MyWindow::on_label_leave));
    
    grid.add(eventbox);
    grid.add(checkbutton);
    grid.attach(button, 0, 1);
    
    add(grid);
    
    arrange_content_layout();
    set_default_size(120, 60);
    
    show_all();
}

int main()
{
    auto app = Application::create("domain.reverse.sample.rtl-checkbutton");
    
    MyWindow window;
    
    return app->run(window);
}

内容的提问来源于stack exchange，提问作者Keyikedalube Ndang