你知道如何在GTK 3中创建自定义小部件?我试图在C中继承GtkDrawingArea数小时。 Gnome.org仅提供了关于如何继承G_OBJECT的简洁教程。我的问题是,G_Object
/GTK
失败GTK_WIDGET
铸造时查看我的自定义StrokerNodalContainer
为GtkWidget
一个子类,甚至是艰难的我的定义struct
包含这样一行:如何在C中的GTK3中创建自定义小部件?
GtkDrawingArea parent_instance;
它说:
invalid cast from 'StrokerNodalContainer' to 'GtkWidget'
这里是完整的代码,如果你怀疑别的东西可能是错的。这是最小的,所以我没有看到任何外部代码搞乱的原因。
司炉-nodalcontainer.h
#ifndef __STROKER_NODALCONTAINER_H__
#define __STROKER_NODALCONTAINER_H__
#ifndef NO_INCLUDE_WITHIN_HEADERS
#include <gtk/gtk.h>
#endif
#define STROKER_TYPE_NODAL_CONTAINER (stroker_nodal_container_get_type())
#define STROKER_NODAL_CONTAINER(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), STROKER_TYPE_NODAL_CONTAINER, StrokerNodalContainer))
#define STROKER_NODAL_CONTAINER_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), STROKER_TYPE_NODAL_CONTAINER, StrokerNodalContainerClass))
#define STROKER_IS_NODAL_CONTAINER(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), STROKER_TYPE_NODAL_CONTAINER))
#define STROKER_IS_NODAL_CONTAINER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), STROKER_TYPE_NODAL_CONTAINER))
#define STROKER_NODAL_CONTAINER_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), STROKER_TYPE_NODAL_CONTAINER, StrokerNodalContainerClass))
typedef struct _StrokerNodalContainer StrokerNodalContainer;
typedef struct _StrokerNodalContainerClass StrokerNodalContainerClass;
struct _StrokerNodalContainer
{
GtkDrawingArea parent_instance;
};
struct _StrokerNodalContainerClass
{
GtkDrawingAreaClass parent_class;
};
GType stroker_nodal_container_get_type(void);
//StrokerNodalContainer* stroker_nodalcontainer_new(void);
#endif /* __STROKER_NODALCONTAINER_H__ */
司炉-nodalcontainer.c
#include <gtk/gtk.h>
#include "stroker-nodalcontainer.h"
G_DEFINE_TYPE(StrokerNodalContainer, stroker_nodal_container, G_TYPE_OBJECT)
static void stroker_nodal_container_class_init(StrokerNodalContainerClass* klass)
{}
static void stroker_nodal_container_init(StrokerNodalContainer* self)
{
GdkRGBA c;
GtkWidget *widget;
gdk_rgba_parse(&c, "blue");
widget = GTK_WIDGET(self);
gtk_widget_override_background_color(widget, GTK_STATE_FLAG_NORMAL, &c);
}
的main.c
#include <stdlib.h>
#include <stdio.h>
#include <gtk/gtk.h>
#include <cairo/cairo.h>
#include "stroker-nodalcontainer.h"
int main(int argc, char *argv[])
{
GtkWidget *window;
GtkWidget *nodalWidget;
gtk_init(&argc, &argv);
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW (window), "Stroker");
g_signal_connect(window, "destroy", G_CALLBACK (gtk_main_quit), NULL);
gtk_container_set_border_width(GTK_CONTAINER(window), 10);
gtk_widget_show (window);
nodalWidget = g_object_new(STROKER_TYPE_NODAL_CONTAINER,NULL);
gtk_container_add(GTK_CONTAINER(window), nodalWidget);
gtk_widget_show (nodalWidget);
gtk_main();
return EXIT_SUCCESS;
}
Ť要求任何帮助!
在官方wiki上有一个例子,但它使用的是Vala,而不是C,https://wiki.gnome.org/Projects/Vala/CustomWidgetSamples – user2485710 2014-09-13 15:10:10
是的,但Vala或C++或Java或Python非常简单:类继承特性是语言的核心,所以他们只是使用它。我无法识别我的GObject继承。 – 2014-09-13 16:09:46
Vala编译为C89 + Glib + Gobject,我建议如下:在Vala中编写基本的代码,将Vala编译为C,检查生成的C代码。 – user2485710 2014-09-13 16:13:35