这方面的资料确实比较少，通过自己摸索，实现了在GTK+ 2.0下进行图片显示，然后在图片上可以自己绘图的一个程序。啥也不说了，发上源码，以供大家参考。希望对学习GTK+的人有点帮助。 #include <gtk/gtk.h>#include <stdlib.h>#include <gdk-pixbuf/gdk-pixbuf.h>   #define DA_WIDTH 300 #define DA_HEIGHT 300 #define SCALE_FACTOR 1.2 #define PEN_MOVE  0#define PEN_UP    1#define PEN_DOWN  2 GdkPixmap *pixmap = NULL;GtkWidget *window, *vbox, *tool_bar, *drawing_area; gboolean status;gboolean fdiscard = TRUE; gint prev_x, prev_y;GdkGC *my_gc_red;GdkColor color; struct ImageData {   GtkWidget *drawing_area;   int width, height;   GdkPixbuf *pixbuf;   float scale; }; struct ImageData data; static void expose_cb(GtkWidget *da, GdkEventExpose *event, struct ImageData *data){  gdk_pixbuf_render_to_drawable_alpha(data->pixbuf, da->window, 0, 0,           0, 0, data->width, data->height,           GDK_PIXBUF_ALPHA_FULL, 0,           GDK_RGB_DITHER_NONE, 0, 0); } static void zoom(struct ImageData *data, float scale) {   GdkPixbuf *pixbuf;   int width  = data->width  * scale;   int height = data->height * scale;     pixbuf = gdk_pixbuf_scale_simple(data->pixbuf, width, height,GDK_INTERP_BILINEAR);   if (pixbuf) {     gdk_pixbuf_unref(data->pixbuf);     data->pixbuf = pixbuf;     data->width  = width;     data->height = height;   }     gdk_window_clear(data->drawing_area->window);   expose_cb(data->drawing_area, NULL, data); }   static void zoom_in_cb(GtkWidget *widget, struct ImageData *data) {   zoom(data, SCALE_FACTOR); }   static void zoom_out_cb(GtkWidget *widget, struct ImageData *data) {   zoom(data, 1.0 / SCALE_FACTOR); } static void clear(GtkWidget *widget){  int width, height;  gtk_window_get_size(window, &width, &height);  printf("width=%d, height=%d\n",width,height);  gdk_draw_rectangle(pixmap ,              drawing_area->style->white_gc ,              TRUE , 0 , 0 ,              width,height);                  //drawing_area->allocation.width ,              //drawing_area->allocation.height);     gtk_widget_queue_draw(drawing_area);} static gboolean configure_event( GtkWidget         *widget,                                 GdkEventConfigure *event ){         if (pixmap)    g_object_unref (pixmap);   pixmap = gdk_pixmap_new (widget->window,      widget->allocation.width,      widget->allocation.height,      -1);  gdk_draw_rectangle (pixmap,        widget->style->white_gc,        TRUE,        0, 0,        //1,1);        widget->allocation.width,        widget->allocation.height);          my_gc_red = gdk_gc_new(widget->window);  color.red = 0;  color.green = 0;  color.blue = 0;  gdk_gc_set_rgb_fg_color(my_gc_red , &color);    gint line_width =2;  GdkLineStyle line_style= GDK_LINE_SOLID;  GdkCapStyle cap_style=GDK_CAP_NOT_LAST;  GdkJoinStyle join_style=GDK_JOIN_MITER;  gdk_gc_set_line_attributes (my_gc_red,line_width, line_style, cap_style,join_style);  return TRUE;} static void draw_line(GtkWidget *widget, gint prev_x, gint prev_y, gint x, gint y) //Miao{     GdkRectangle update_rect;     if(prev_x < x) update_rect.x = prev_x; else update_rect.x = x;     if(prev_y < y) update_rect.y = prev_y; else update_rect.y = y;          if(prev_x < x) update_rect.width = x-prev_x; else update_rect.width = prev_x-x;     if(prev_y < y) update_rect.height = y-prev_y; else update_rect.height = prev_y-y;          if(update_rect.width == 0 && update_rect.height == 0)         return;               gdk_draw_line(/*pixmap*/drawing_area->window, my_gc_red, prev_x, prev_y, x, y); //    gtk_widget_queue_draw_area(widget , //                  update_rect.x-5 , update_rect.y-5 , update_rect.width+10, update_rect.height+10); } static gboolean button_press_event( GtkWidget      *widget,                                    GdkEventButton *event ){  status = PEN_DOWN;        prev_x =event->x;   prev_y =event->y;   return TRUE;} static gboolean button_release_event(GtkWidget       *widget,                                     GdkEventButton  *event){  status = PEN_UP;//  printf("Up: x=%d, y=%d\n",(gint)prev_x,(gint)prev_y);   return TRUE;       }                                     static gboolean motion_notify_event( GtkWidget *widget,                                     GdkEventMotion *event ){  int x, y;  GdkModifierType state;    if (event->is_hint)  {    gdk_window_get_pointer (event->window, &x, &y, &state);  }  else  {      x = event->x;      y = event->y;      state = event->state;  }      fdiscard = (fdiscard == FALSE ? TRUE: FALSE);  if(status == PEN_DOWN && pixmap != NULL)  {        if(fdiscard == TRUE)        {           draw_line(widget,prev_x, prev_y,x,y);           prev_x = x;           prev_y = y;        }          }    return TRUE;} int main(int argc, char *argv[]){ //  GtkWidget *window, *vbox, *tool_bar, *drawing_area;   GdkPixbuf *pixbuf; //  struct ImageData data;    #ifdef DEBUG  int wid, heig;  #endif /*  if (argc != 2) {     printf("Usage: %s image_file\n", argv[0]);     exit(1);   }*/   gtk_init (&argc, &argv);   /* Create top level window */      window = gtk_window_new(GTK_WINDOW_TOPLEVEL);   gtk_window_set_title(GTK_WINDOW(window), "Laser Gesture Operation");  gtk_widget_set_size_request(GTK_WINDOW(window), 800, 800);   gtk_signal_connect(GTK_OBJECT(window), "destroy",   GTK_SIGNAL_FUNC(gtk_main_quit), NULL);         #ifdef DEBUG  gtk_window_get_size(GTK_WINDOW(window), &wid, &heig);  printf("Top level window size: x=%d, y=%d\n",wid,heig);  #endif   /* Create an image if any */   pixbuf = gdk_pixbuf_new_from_file(/*argv[1]*/"1.jpg",NULL);   if (pixbuf == NULL) {     printf("Error: can't load picture file \"%s\"\n", argv[1]);     exit(2);   }   data.pixbuf = pixbuf;   data.width  = gdk_pixbuf_get_width(pixbuf);   data.height = gdk_pixbuf_get_height(pixbuf);   data.scale  = 1.0;     /* Create box container */   vbox = gtk_vbox_new(FALSE, 0);   gtk_container_add(GTK_CONTAINER(window), vbox);     /* Create tool bar */ //  tool_bar = gtk_toolbar_new(GTK_ORIENTATION_HORIZONTAL, GTK_TOOLBAR_BOTH);    tool_bar = gtk_toolbar_new();   gtk_toolbar_set_style (GTK_TOOLBAR(tool_bar), GTK_TOOLBAR_TEXT); //  gtk_toolbar_set_space_style (GTK_TOOLBAR(tool_bar), GTK_TOOLBAR_SPACE_LINE);   gtk_box_pack_start(GTK_BOX(vbox), tool_bar, FALSE, FALSE, 2);     /* Create zoom tools */   gtk_toolbar_append_item(GTK_TOOLBAR(tool_bar), "+", "Zoom in",      NULL, NULL, /* icon */      GTK_SIGNAL_FUNC(zoom_in_cb), &data);   gtk_toolbar_append_item(GTK_TOOLBAR(tool_bar), "-", "Zoom out",      NULL, NULL, /* icon */      GTK_SIGNAL_FUNC(zoom_out_cb), &data);   gtk_toolbar_append_item(GTK_TOOLBAR(tool_bar), "Clear", "Clear",      NULL, NULL, /* icon */      GTK_SIGNAL_FUNC(clear), NULL);       gtk_toolbar_append_item(GTK_TOOLBAR(tool_bar), "Quit", NULL,      NULL, NULL, /* icon */      GTK_SIGNAL_FUNC(gtk_main_quit), NULL);     /* Create a drawing area. */   drawing_area = gtk_drawing_area_new();   #ifdef DEBUG  gtk_widget_set_size_request(GTK_WIDGET(drawing_area), wid, heig);  #else  gtk_wdiget_set_size_request(GTK_WIDGET(drawing_area), DA_WIDTH, DA_HEIGHT);  #endif    gtk_box_pack_start (GTK_BOX(vbox), drawing_area, TRUE, TRUE, 2);    gtk_widget_set_events (drawing_area, GDK_EXPOSURE_MASK    | GDK_LEAVE_NOTIFY_MASK    | GDK_BUTTON_PRESS_MASK    | GDK_POINTER_MOTION_MASK    | GDK_BUTTON_RELEASE_MASK    | GDK_POINTER_MOTION_HINT_MASK);   gtk_signal_connect(GTK_OBJECT(drawing_area), "expose_event",       GTK_SIGNAL_FUNC(expose_cb), &data);         gtk_signal_connect(GTK_OBJECT(drawing_area), "configure_event",             G_CALLBACK(configure_event),NULL);         g_signal_connect (G_OBJECT(drawing_area), "motion_notify_event",      G_CALLBACK (motion_notify_event), NULL);        g_signal_connect (G_OBJECT(drawing_area), "button_press_event",      G_CALLBACK (button_press_event), drawing_area);        g_signal_connect (G_OBJECT(drawing_area), "button_release_event",      G_CALLBACK (button_release_event), drawing_area);   data.drawing_area = drawing_area;   /* Show and go */  //  gtk_widget_show(drawing_area); //  gtk_widget_show(tool_bar); //  gtk_widget_show(vbox);   gtk_widget_show_all (window);   gtk_main();     return(0); }  

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