Ubuntu22.04 gnome-builder gnome C 应用程序习练笔记(三)

八、ui窗体创建要点

.h文件定义(popwindowf.h)， TEST_TYPE_WINDOW宏是要创建的窗口样式。

#pragma once
#include <gtk/gtk.h>
G_BEGIN_DECLS
#define TEST_TYPE_WINDOW (test_window_get_type())
G_DECLARE_FINAL_TYPE (TestWindow, test_window, TEST, WINDOW, GtkWindow)
G_END_DECLS

g_object_new时生产TEST_TYPE_WINDOW，后面的参数是窗口的属性。

    window = g_object_new (TEST_TYPE_WINDOW,
                           "default-height", 550, "default-width", 800,
                           "title", "Nice window!",
                           NULL);

在ui文件里的名字叫 TestWindow ，如果是主窗体，则是项目的工程名+Window ，如 WithcamblaWindow。 ui文件里的template class名字，要和.h文件中的名字一致。

  <template class="TestWindow" parent="GtkWindow">
    <property name="default-height">800</property>
    <property name="default-width">1200</property>

.c文件中的名字也是一致的， TestWindow是产生的新窗体的 handle

struct _TestWindow
{
  GtkWindow  parent_instance;

  /* Template widgets */
  GtkHeaderBar        *header_bar;
  GtkLabel            *label1;
  GtkButton           *button1;
  GtkButton           *button2;
  GtkGrid             *grid1;
};

G_DEFINE_TYPE (TestWindow, test_window, GTK_TYPE_WINDOW)

创建窗体时有两个接口，一是窗口作为一个class的初始化init，另一个是窗体本身的初始化init

static void
test_window_class_init (TestWindowClass *klass)
{
  GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);

  gtk_widget_class_set_template_from_resource (widget_class, "/org/mongnewer/test/popwindowf.ui");
  gtk_widget_class_bind_template_child (widget_class, TestWindow, header_bar);
  gtk_widget_class_bind_template_child (widget_class, TestWindow, label1);
  gtk_widget_class_bind_template_child (widget_class, TestWindow, button1);
  gtk_widget_class_bind_template_child (widget_class, TestWindow, button2);
  gtk_widget_class_bind_template_child (widget_class, TestWindow, grid1);

static void
test_window_init (TestWindow *self)
{
  gtk_widget_init_template (GTK_WIDGET (self));
  g_signal_connect(GTK_WINDOW(self), "destroy", G_CALLBACK(closewindow), self);
}

如果要创建一个叫Passwd窗体，则是PASSWD_TYPE_WINDOW(passwd_window_get_type()),

G_DECLARE_FINAL_TYPE (PasswdWindow, passwd_window, PASSWD, WINDOW, GtkWindow)，ui文件中template class = PasswdWindow，如此，可以考贝已有的.h和.c，然后改动一个名称，注意保持.h .c ui间的名称一致。创建窗体时，用GtkWindow，或GtkApplicationWindow，也是注意保持.h .c ui间窗体样式的一致性。

九、工程添加.c和ui文件

meson和make一样，在meson.build中要加入窗体的 .c， make时就一同make了

新窗体的ui文件要写到resource xml 配置中

写起来挺啰嗦，实现起来只是考贝、修改，名称不一致编译时也会有警告提示的。

十、其它注意事项

如果cambalache不能显示图形，关闭cambalache软件使用硬件加速功能，尤其是在虚拟中运行cambalache，因为没有加速的硬件，所以要关闭它，否则不能显示图形。cambalache是flatpak包，需要安装flatseal包，用flatseal关闭cambalache的硬件加速功能。

ubuntu 22.04 mate-desktop 运行gnome-builder遇到闪退问题的话，sudo apt install tasksel，运行tasksel可选择不同的桌面。

选择gnome桌面可解决问题，窗口管理器依然选用lightdm，不需要选用 gdm3 管理器。问题遇到了、处理掉，就写在这里吧。

GtkApplication简单化编程

gnome-builder构建器功能多，打包方便，但操作也相对繁琐，网上文档零散、不完整，其实，编程的话可以直接写代码，也可以直接写ui文件(gtk4更适合直接写ui)，或是直接用代码创建窗体，这样的话编辑器用简单的geany就可以(可能开始时要辅以gtk4网页帮助)，修改界面非常方便。

下面是一个习练的代码程序

geany 代码窗口

在geany下编译 gcc `pkg-config --cflags gtk4` -o "%e" "%f" `pkg-config --libs gtk4`，显示窗体。

下面是编写的代码

#include <gtk/gtk.h>

void
closewindow(GtkWidget *window, gpointer user_data);

void
newwindow(GtkWindow *window, gpointer user_data)
{
	GtkWindow *windownew = GTK_WINDOW(gtk_window_new());
	gtk_window_set_default_size(GTK_WINDOW(windownew), 400, 300);
	gtk_window_set_title(GTK_WINDOW(windownew), "child window");
	GtkWidget *box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 20);
	gtk_box_set_homogeneous(GTK_BOX(box), TRUE);
	GtkWidget *button = gtk_button_new_with_label("new label");
	gtk_button_set_label(GTK_BUTTON(button), "new pushButton");
	g_signal_connect_swapped(GTK_BUTTON(button), "clicked", G_CALLBACK(&closewindow), windownew);
	g_signal_connect_swapped(GTK_WINDOW(windownew), "destroy", G_CALLBACK(&closewindow), windownew);
	
	GtkWidget *spacer1 = gtk_label_new("");
	GtkWidget *spacer2 = gtk_label_new("");
	
	gtk_box_append(GTK_BOX(box), spacer1);
	gtk_box_append(GTK_BOX(box), button);
	gtk_box_append(GTK_BOX(box), spacer2);
	
	gtk_window_set_child(GTK_WINDOW(windownew), box);
	
	gtk_window_set_transient_for(GTK_WINDOW(windownew), window);
	gtk_window_present(GTK_WINDOW(windownew));
}

void
newwindow1(GtkWindow *window_in, gpointer user_data_in)
{
  GtkBuilder *builder = gtk_builder_new();
  gtk_builder_add_from_file (builder, "builder.ui", NULL);

  /* Connect signal handlers to the constructed widgets. */
  GObject *window = gtk_builder_get_object (builder, "window");
  gtk_window_set_default_size(GTK_WINDOW(window), 600, 350);
  
  GObject *button = gtk_builder_get_object (builder, "button1");
  g_signal_connect_swapped (button, "clicked", G_CALLBACK (closewindow), window);

  button = gtk_builder_get_object (builder, "button2");
  g_signal_connect_swapped (button, "clicked", G_CALLBACK (closewindow), window);

  button = gtk_builder_get_object (builder, "quit");
  g_signal_connect_swapped (button, "clicked", G_CALLBACK (closewindow), window);

  gtk_window_set_transient_for(GTK_WINDOW(window), window_in);
  gtk_widget_show (GTK_WIDGET (window));

  /* We do not need the builder any more */
  g_object_unref (builder);
}

void
closewindow(GtkWidget *window, gpointer user_data)
{
	gtk_window_destroy(GTK_WINDOW(window));
}

static void
activate (GtkApplication* app,
          gpointer        user_data)
{
  GtkWidget *window;

  window = gtk_application_window_new (app);
  gtk_window_set_title (GTK_WINDOW (window), "Parent Window");
  gtk_window_set_default_size (GTK_WINDOW (window), 800, 600);
  
  GtkWidget *box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 20);
  gtk_box_set_homogeneous(GTK_BOX(box), TRUE);
  GtkWidget *button = gtk_button_new();
  GtkWidget *button1 = gtk_button_new();
  gtk_button_set_label(GTK_BUTTON(button), "pushButton");
  gtk_button_set_label(GTK_BUTTON(button1), "pushButton1");
  
  g_signal_connect_swapped(GTK_BUTTON(button), "clicked", G_CALLBACK(&newwindow), window);
  g_signal_connect_swapped(GTK_BUTTON(button1), "clicked", G_CALLBACK(&newwindow1), window);
  g_signal_connect_swapped(GTK_WINDOW(window), "destroy", G_CALLBACK(&closewindow), window);
  
  GtkWidget *spacer1 = gtk_label_new("");
  GtkWidget *spacer2 = gtk_label_new("");
  gtk_box_append(GTK_BOX(box), spacer1);
  gtk_box_append(GTK_BOX(box), button);
  gtk_box_append(GTK_BOX(box), button1);
  gtk_box_append(GTK_BOX(box), spacer2);
  
  gtk_window_set_child(GTK_WINDOW(window), box);
    
  gtk_widget_show (window);
}

int
main (int    argc,
      char **argv)
{
  GtkApplication *app;
  int status;

  app = gtk_application_new ("org.gtk.example", G_APPLICATION_FLAGS_NONE);
  g_signal_connect (app, "activate", G_CALLBACK (activate), NULL);
  status = g_application_run (G_APPLICATION (app), argc, argv);
  g_object_unref (app);

  return status;
}

下面是简单化的手写ui(复制、粘贴、修改)

<?xml version="1.0" encoding="UTF-8"?>
<interface>
  <object id="window" class="GtkWindow">
    <property name="title">Grid</property>
    <child>
      <object id="grid" class="GtkGrid">
        <property name="column-homogeneous">True</property>
        <property name="column-spacing">10</property>
        <property name="hexpand">True</property>
        <property name="hexpand-set">True</property>
        <property name="row-homogeneous">True</property>
        <property name="row-spacing">10</property>
        <property name="vexpand">True</property>
        <property name="vexpand-set">True</property>
        <child>
          <object id="spacer1" class="GtkLabel">
            <property name="label"></property>
            <layout>
              <property name="column">0</property>
              <property name="column-span">4</property>
              <property name="row">0</property>
            </layout>
          </object>
        </child>
        <child>
          <object id="button1" class="GtkButton">
            <property name="label">Button 1</property>
            <layout>
              <property name="column">1</property>
              <property name="row">1</property>
            </layout>
          </object>
        </child>
        <child>
          <object id="button2" class="GtkButton">
            <property name="label">Button 2</property>
            <layout>
              <property name="column">2</property>
              <property name="row">1</property>
            </layout>
          </object>
        </child>
        <child>
          <object id="quit" class="GtkButton">
            <property name="label">Quit</property>
            <layout>
              <property name="column">1</property>
              <property name="row">2</property>
              <property name="column-span">2</property>
            </layout>
          </object>
        </child>
        <child>
          <object id="spacer2" class="GtkLabel">
            <property name="label"></property>
            <layout>
              <property name="column">0</property>
              <property name="column-span">4</property>
              <property name="row">3</property>
            </layout>
          </object>
        </child>
      </object>
    </child>
  </object>
</interface>

ui写着不顺手时装到cambalache里完善一下再export出来接着手改完善，还是比较方便的。