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。