gtk+实现透明窗口

http://blog.chinaunix.net/u/27977/showart_213718.html

先用gimp制作一个有透明背景的图片，并存为shape1.xpm格式。



编写代码：
我有点懒，过程以后慢慢再写.下面附有源代码。

编译运行：
$gcc shape1.c -o shape1 `pkg-config --cflags --libs gtk+-2.0`
$./shape1

运行效果图：

源代码:

/* vi: set sw=4 ts=4: */
/****************************************************************************
 *
 * Copyright (C) 2006 by yetist <[email protected]>.
 *
 * 文 件 名:shape1.c
 * 版 本:0.1
 * 创建时间:2006年12月11日 星期一 23时21分26秒
 * 描 述:________
 *
 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
 *****************************************************************************/

#include <gtk/gtk.h>
typedef struct _cursoroffset {gint x,y;} CursorOffset;

static void
shape_pressed (GtkWidget *widget, GdkEventButton *event)
{
    CursorOffset *p;

    if (event->type != GDK_BUTTON_PRESS)
        return;

    p = g_object_get_data (G_OBJECT (widget), "cursor_offset");
    p->x = (int) event->x;
    p->y = (int) event->y;

    gtk_grab_add (widget);
    gdk_pointer_grab (widget->window, TRUE,
            GDK_BUTTON_RELEASE_MASK |
            GDK_BUTTON_MOTION_MASK |
            GDK_POINTER_MOTION_HINT_MASK,
            NULL, NULL, 0);
}

static void
shape_released (GtkWidget *widget)
{
    gtk_grab_remove (widget);
    gdk_display_pointer_ungrab (gtk_widget_get_display (widget),
            GDK_CURRENT_TIME);
}

static void
shape_motion (GtkWidget *widget,
        GdkEventMotion *event)
{
    gint xp, yp;
    CursorOffset * p;
    GdkModifierType mask;

    p = g_object_get_data (G_OBJECT (widget), "cursor_offset");

    gdk_window_get_pointer (NULL, &xp, &yp, &mask);
    gdk_window_move (widget->window, xp- p->x, yp-p->y);
}

    int
main (gint argc, gchar** argv)
{
    GtkWidget *window;
    GtkWidget *pixmap;
    GtkWidget *fixed;
    GdkGC* gc;
    GdkBitmap *gdk_pixmap_mask;
    GdkPixmap *gdk_pixmap;
    GtkStyle *style;
    GdkScreen *screen;
    CursorOffset* icon_pos;
    gchar *xpm_file = "shape1.xpm";

    gtk_init (&argc, &argv);

    screen = gdk_screen_get_default();
    style = gtk_widget_get_default_style ();
    gc = style->black_gc;    
    window = gtk_window_new (GTK_WINDOW_POPUP);
    gtk_window_set_screen (GTK_WINDOW (window), screen);
    gtk_window_set_position (GTK_WINDOW(window), GTK_WIN_POS_CENTER);

    fixed = gtk_fixed_new ();
    gtk_widget_set_size_request (fixed, 440, 120);
    gtk_container_add (GTK_CONTAINER (window), fixed);
    gtk_widget_show (fixed);

    gtk_widget_set_events (window,
            gtk_widget_get_events (window) |
            GDK_BUTTON_MOTION_MASK |
            GDK_POINTER_MOTION_HINT_MASK |
            GDK_BUTTON_PRESS_MASK);

    gtk_widget_realize (window);

    gdk_pixmap = gdk_pixmap_create_from_xpm (window->window, &gdk_pixmap_mask,
            &style->bg[GTK_STATE_NORMAL],
            xpm_file);

    pixmap = gtk_image_new_from_pixmap (gdk_pixmap, gdk_pixmap_mask);
    gtk_fixed_put (GTK_FIXED (fixed), pixmap, 0, 0);
    gtk_widget_show (pixmap);

    gtk_widget_shape_combine_mask (window, gdk_pixmap_mask, 0, 0);

    g_object_unref (gdk_pixmap_mask);
    g_object_unref (gdk_pixmap);

    g_signal_connect (window, "button_press_event",
            G_CALLBACK (shape_pressed), NULL);
    g_signal_connect (window, "button_release_event",
            G_CALLBACK (shape_released), NULL);
    g_signal_connect (window, "motion_notify_event",
            G_CALLBACK (shape_motion), NULL);
    g_signal_connect (window, "delete_event",
            G_CALLBACK (gtk_widget_destroyed), NULL);
    g_signal_connect (window, "destroy",
            G_CALLBACK (gtk_widget_destroyed), NULL);

    icon_pos = g_new (CursorOffset, 1);
    g_object_set_data (G_OBJECT (window), "cursor_offset", icon_pos);

    gtk_widget_show_all (window);

    gtk_main();
    return 1;
}