我有一个简单的 C
GTK
Linux 应用程序,它需要将主窗口的背景设置为来自 GIF
的图像文件。我做了一些阅读,看来我应该能够做到以下几点:
1- stuff the background image into a
GdkPixbuf
usinggdk_pixbuf_new_from_file()
2- usegdk_pixbuf_render_pixmap_and_mask()
to render theGdkPixbuf
into aGdkPixMap
3- set the background of theGtkWindow
usinggdk_window_set_back_pixmap()
对 gdk_window_set_back_pixmap()
的调用似乎需要 GdKWindow
而不是 GtkWindow
。我的代码不起作用,下面是我的具体问题。
/* * Compile me with: * gcc -o reels reels.c $(pkg-config --cflags --libs gtk+-2.0 gmodule-2.0) */ #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <stdio.h> #include <string.h> #include <stdlib.h> #include <errno.h> #include <time.h> /* GTK */ #include <gdk/gdkx.h> #include <gtk/gtk.h> /**** prototypes ****/ static void destroy (GtkWidget*, gpointer); GdkPixbuf *create_pixbuf(const gchar * filename); /********************/ GtkWidget *images[3][5]; static void destroy (GtkWidget *window, gpointer data) { gtk_main_quit (); } GdkPixbuf *create_pixbuf(const gchar * filename) { GdkPixbuf *pixbuf; GError *error = NULL; pixbuf = gdk_pixbuf_new_from_file(filename, &error); if(!pixbuf) { fprintf(stderr, "%s\n", error->message); g_error_free(error); } return pixbuf; } int main (int argc, char *argv[]) { GtkWidget *window, *table; GdkPixbufAnimation *animation; GtkWidget *image; int x,y; GdkPixbuf *pixBuf; GdkPixmap *pixMap; gtk_init (&argc, &argv); window = gtk_window_new (GTK_WINDOW_TOPLEVEL); gtk_window_set_default_size (GTK_WINDOW (window), 628, 530); gtk_window_set_title (GTK_WINDOW (window), "Demo"); gtk_container_set_border_width (GTK_CONTAINER (window), 10); //gtk_window_set_decorated( GTK_WINDOW(window), FALSE ); pixBuf = create_pixbuf("background.gif"); gdk_pixbuf_render_pixmap_and_mask(pixBuf, &pixMap, NULL, 255); gdk_window_set_back_pixmap( GDK_WINDOW (window), pixMap, (gboolean) TRUE); #if 0 /* some code I found that is supposed to create a background image.. Can't seem to get it converted correctly into 'C' */ area=gtk.Drawingarea() pixbuf=gtk.gdk.pixbuf_new_from_file('background.png') pixmap, mask=pixbuf.render_pixmap_and_mask() area.window.set_back_pixmap(pixmap, False) #endif g_signal_connect (G_OBJECT (window), "destroy", G_CALLBACK (destroy), NULL); table = gtk_table_new (3, 5, TRUE); /* setup animated gifs */ for( y = 0; y < 3; y++ ) { for( x = 0; x < 5; x++ ) { /* set each Image widget to spin GIF */ images[y][x] = gtk_image_new_from_file("spinning.gif");; gtk_table_attach (GTK_TABLE (table), images[y][x], x, x+1, y, y+1, GTK_EXPAND, GTK_SHRINK, 0, 0); } } /* Add five pixels of spacing between every row and every column. */ gtk_table_set_row_spacings (GTK_TABLE (table), 5); gtk_table_set_col_spacings (GTK_TABLE (table), 5); gtk_container_add (GTK_CONTAINER (window), table); gtk_widget_show_all (window); gtk_main (); return 0; }
代码编译并运行,但出现以下运行时错误(这是我预料到的,因为我不知道如何从 GtkWindow
派生 GdkWindow
:
(reels:10951): GLib-GObject-WARNING **: invalid cast from
GtkWindow' to
GdkWindow'(reels:10951): Gdk-CRITICAL **: gdk_window_set_back_pixmap: assertion `GDK_IS_WINDOW (window)' failed
我的问题是:
1- 如何从代码主窗口 (GtkWindow
) 派生出 GdkWindow
?
2- 我是否需要使用绘图区?
3- 我需要做什么才能将 background.gif
图像显示为主窗口的背景?
如有任何帮助,我们将不胜感激。我看过很多代码片段,但很难将它们放在一起,而且我对 Gtk
还是很陌生。
最佳答案
My questions are:
1- How do I derive a GdkWindow from the codes main window ( GtkWindow )?
2- Do I need to use a Drawing Area at all?
3- What do I need to do get the background.gif image displayed as the background on the main >window?
如果你想在你的 gtk 窗口中设置一个像背景一样的图像,你应该这样做:
1 - 将图像加载到 GdkPixbuf 或变体。 (gdk_pixbuf_new_from_file)
2 - 创建一个像素图和一个掩码位图。 (gdk_pixbuf_render_pixmap_and_mask () )
3 - 创建一个 GtkStyle 来保存小部件的样式信息。
4 - 加载渲染像素图到样式。
5 - 将 GtkStyle 设置为主窗口。
一个例子:
#include <gtk/gtk.h>
#include <stdio.h>
#include <stdlib.h>
GdkPixbuf *load_pixbuf_from_file (const char *filename)
{
GError *error = NULL;
GdkPixbuf *pixbuf = gdk_pixbuf_new_from_file (filename, &error);
if (pixbuf == NULL)
{
g_print ("Error loading file: %d : %s\n", error->code, error->message);
g_error_free (error);
exit (1);
}
return pixbuf;
}
GdkPixbufAnimation *load_pixbuf_animation_from_file (const char *filename)
{
GError *error = NULL;
GdkPixbufAnimation *pixbuf = gdk_pixbuf_animation_new_from_file (filename, &error);
if (pixbuf == NULL)
{
g_print ("Error loading file: %d : %s\n", error->code, error->message);
g_error_free (error);
exit (1);
}
return pixbuf;
}
int main (int argc, char **argv)
{
GtkWidget *window = NULL;
GdkPixbuf *image = NULL;
GdkPixbufAnimation * anim = NULL;
GtkWidget *widget = NULL;
GdkPixmap *background = NULL;
GtkStyle *style = NULL;
gtk_init (&argc, &argv);
/* Load a non animated gif */
image = load_pixbuf_from_file ("/home/midnigther/Desktop/pict.gif");
// widget = gtk_image_new_from_pixbuf (image);
gdk_pixbuf_render_pixmap_and_mask (image, &background, NULL, 0);
style = gtk_style_new ();
style->bg_pixmap [0] = background;
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_title (GTK_WINDOW(window), "Load Image");
gtk_window_set_default_size (GTK_WINDOW (window), 400, 300);
gtk_widget_set_style (GTK_WIDGET(window), GTK_STYLE (style));
gtk_window_set_transient_for (GTK_WINDOW (window), NULL);
GtkWidget *hbox = NULL;
hbox = gtk_hbox_new (0, FALSE);
gtk_container_add (GTK_CONTAINER(window), hbox);
GtkWidget *button = NULL;
button = gtk_button_new_with_label ("Sonic");
gtk_box_pack_start (GTK_BOX (hbox), button, FALSE, FALSE, 0);
gtk_widget_show_all (window);
gtk_main ();
return 0;
}
关于c - 如何将 GtkWindow 的背景设置为图像?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/10823256/