gtkmm4 应用程序使用 CSS 样式

前言

• 程序样式和代码逻辑分离开 使代码逻辑更可观

css选择器

• Cambalache提供了两种
• css-classes 相当于css里的类名:class=“类名”
• css-name 相当于css里的标签名:spin div p 啥的
  
• 如上我设置了这个按钮控件的类名为testButton
  标签名为myButton
• 它的Xml视图是这样的

  <?xml version='1.0' encoding='UTF-8'?>
  <!-- Created with Cambalache 0.16.0 -->
  <interface><!-- interface-name temp3.ui --><requires lib="gtk" version="4.12"/><object class="GtkButton" id="Button1"><property name="css-classes">testButton</property><property name="css-name">myButton</property><property name="focusable">True</property><property name="hexpand">True</property><property name="label">Button1</property><property name="vexpand">True</property><property name="vexpand-set">True</property></object>
  </interface>
  

css文件示例

.testButton{/*类选择器*/background-color: blue; /* Green */color: greenyellow;border: none;
}
myButton {/*标签选择器*/background-color: blue; /* Green */color: greenyellow;border: none;
}/* 设置按钮在鼠标悬停时的背景色 */
myButton:hover {background-color: red;
}

源代码

#include <gtkmm.h>
#include <iostream>
class MainWindow : public Gtk::Window
{
public:// Member widgets:MainWindow(){// Set window propertiesset_title("GTKMM4 with CSS Example");set_default_size(200, 200);auto refBuilder= Gtk::Builder::create_from_file("K:\\VM_Shared\\temp3.ui");auto pButton = refBuilder->get_widget<Gtk::Button>("Button1");set_child(*pButton);pButton->set_visible();// Load CSS stylesload_css();}private:void load_css(){// Check if CSS file existsif (Glib::file_test("K:\\VM_Shared\\Style.css", Glib::FileTest::EXISTS)){// Create CSS provider and load CSS fileauto css_provider = Gtk::CssProvider::create();css_provider->load_from_path("K:\\VM_Shared\\Style.css");// Get the default screen and add the CSS providerauto screen = Gdk::Display::get_default();Gtk::StyleContext::add_provider_for_display(screen, css_provider,GTK_STYLE_PROVIDER_PRIORITY_APPLICATION );}else{std::cerr << "Failed to load CSS file: styles.css" << std::endl;}}
};int main(int argc, char* argv[])
{auto app=Gtk::Application::create("org.HelleCssExample");return app->make_window_and_run<MainWindow>(argc, argv);
}

效果

动态设置css-classes

auto button1 = Gtk::make_managed<Gtk::Button>("bottom button");
button1->set_expand();
button1->get_style_context()->add_class("custom_button");