Demonstrate image copy-and-paste and DND, and clipboard persistency.

2005-05-25  Matthias Clasen  <mclasen@redhat.com>

	* demos/gtk-demo/clipboard.c: Demonstrate image copy-and-paste
	and DND, and clipboard persistency.

1 files changed, 208 insertions, 10 deletions

diff --git a/demos/gtk-demo/clipboard.c b/demos/gtk-demo/clipboard.c
index 251b165a1..96a993db5 100644
--- a/demos/gtk-demo/clipboard.c
+++ b/demos/gtk-demo/clipboard.c
@@ -1,7 +1,12 @@
 /* Clipboard
  *
  * GtkClipboard is used for clipboard handling. This demo shows how to
- * copy and paste text to and from the clipboard.
+ * copy and paste text to and from the clipboard. 
+ *
+ * It also shows how to transfer images via the clipboard or via 
+ * drag-and-drop, and how to make clipboard contents persist after
+ * the application exits. Clipboard persistence requires a clipboard
+ * manager to run.
  */
 
 #include <gtk/gtk.h>
@@ -11,7 +16,7 @@ static GtkWidget *window = NULL;
 
 void
 copy_button_clicked (GtkWidget *button,
-		     gpointer   user_data)
+                     gpointer   user_data)
 {
   GtkWidget *entry;
   GtkClipboard *clipboard;
@@ -20,7 +25,7 @@ copy_button_clicked (GtkWidget *button,
   
   /* Get the clipboard object */
   clipboard = gtk_widget_get_clipboard (entry,
-					GDK_SELECTION_CLIPBOARD);
+                                        GDK_SELECTION_CLIPBOARD);
 
   /* Set clipboard text */
   gtk_clipboard_set_text (clipboard, gtk_entry_get_text (GTK_ENTRY (entry)), -1);
@@ -28,8 +33,8 @@ copy_button_clicked (GtkWidget *button,
 
 void
 paste_received (GtkClipboard *clipboard,
-		const gchar  *text,
-		gpointer      user_data)
+                const gchar  *text,
+                gpointer      user_data)
 {
   GtkWidget *entry;
 
@@ -41,7 +46,7 @@ paste_received (GtkClipboard *clipboard,
 
 void
 paste_button_clicked (GtkWidget *button,
-		     gpointer   user_data)
+                     gpointer   user_data)
 {
   GtkWidget *entry;
   GtkClipboard *clipboard;
@@ -50,13 +55,139 @@ paste_button_clicked (GtkWidget *button,
   
   /* Get the clipboard object */
   clipboard = gtk_widget_get_clipboard (entry,
-					GDK_SELECTION_CLIPBOARD);
+                                        GDK_SELECTION_CLIPBOARD);
 
   /* Request the contents of the clipboard, contents_received will be
      called when we do get the contents.
    */
   gtk_clipboard_request_text (clipboard,
-			      paste_received, entry);
+                              paste_received, entry);
+}
+
+static GdkPixbuf *
+get_image_pixbuf (GtkImage *image)
+{
+  gchar *stock_id;
+  GtkIconSize size;
+
+  switch (gtk_image_get_storage_type (image))
+    {
+    case GTK_IMAGE_PIXBUF:
+      return g_object_ref (gtk_image_get_pixbuf (image));
+    case GTK_IMAGE_STOCK:
+      gtk_image_get_stock (image, &stock_id, &size);
+      return gtk_widget_render_icon (GTK_WIDGET (image),
+                                     stock_id, size, NULL);
+    default:
+      g_warning ("Image storage type %d not handled", 
+                 gtk_image_get_storage_type (image));
+      return NULL;
+    }
+}
+
+static void
+drag_begin (GtkWidget      *widget,
+            GdkDragContext *context,
+            gpointer        data)
+{
+  GdkPixbuf *pixbuf;
+
+  pixbuf = get_image_pixbuf (GTK_IMAGE (data));
+  gtk_drag_set_icon_pixbuf (context, pixbuf, -2, -2);
+  g_object_unref (pixbuf);
+}
+
+void  
+drag_data_get  (GtkWidget        *widget,
+                GdkDragContext   *context,
+                GtkSelectionData *selection_data,
+                guint             info,
+                guint             time,
+                gpointer          data)
+{
+  GdkPixbuf *pixbuf;
+
+  pixbuf = get_image_pixbuf (GTK_IMAGE (data));
+  gtk_selection_data_set_pixbuf (selection_data, pixbuf);
+  g_object_unref (pixbuf);
+}
+
+static void
+drag_data_received (GtkWidget        *widget,
+                    GdkDragContext   *context,
+                    gint              x,
+                    gint              y,
+                    GtkSelectionData *selection_data,
+                    guint             info,
+                    guint32           time,
+                    gpointer          data)
+{
+  GdkPixbuf *pixbuf;
+
+  if (selection_data->length > 0)
+    {
+      pixbuf = gtk_selection_data_get_pixbuf (selection_data);
+      gtk_image_set_from_pixbuf (GTK_IMAGE (data), pixbuf);
+      g_object_unref (pixbuf);
+    }
+}
+
+static void
+copy_image (GtkMenuItem *item,
+            gpointer     data)
+{
+  GtkClipboard *clipboard;
+  GdkPixbuf *pixbuf;
+
+  clipboard = gtk_clipboard_get (GDK_SELECTION_CLIPBOARD);
+  pixbuf = get_image_pixbuf (GTK_IMAGE (data));
+
+  gtk_clipboard_set_image (clipboard, pixbuf);
+  g_object_unref (pixbuf);
+}
+
+static void
+paste_image (GtkMenuItem *item,
+             gpointer     data)
+{
+  GtkClipboard *clipboard;
+  GdkPixbuf *pixbuf;
+
+  clipboard = gtk_clipboard_get (GDK_SELECTION_CLIPBOARD);
+  pixbuf = gtk_clipboard_wait_for_image (clipboard);
+
+  if (pixbuf)
+    {
+      gtk_image_set_from_pixbuf (GTK_IMAGE (data), pixbuf);
+      g_object_unref (pixbuf);
+    }
+}
+
+static gboolean
+button_press (GtkWidget      *widget,
+              GdkEventButton *button,
+              gpointer        data)
+{
+  GtkWidget *menu;
+  GtkWidget *item;
+  
+  if (button->button != 3)
+    return FALSE;
+
+  menu = gtk_menu_new ();
+  
+  item = gtk_image_menu_item_new_from_stock (GTK_STOCK_COPY, NULL);
+  g_signal_connect (item, "activate", G_CALLBACK (copy_image), data);
+  gtk_widget_show (item);
+  gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
+
+  item = gtk_image_menu_item_new_from_stock (GTK_STOCK_PASTE, NULL);
+  g_signal_connect (item, "activate", G_CALLBACK (paste_image), data);
+  gtk_widget_show (item);
+  gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
+
+  gtk_menu_popup (GTK_MENU (menu), NULL, NULL, NULL, NULL, 3, button->time);
+  return TRUE;
 }
 
 GtkWidget *
@@ -67,8 +198,13 @@ do_clipboard (GtkWidget *do_widget)
       GtkWidget *vbox, *hbox;
       GtkWidget *label;
       GtkWidget *entry, *button;
+      GtkWidget *ebox, *image;
+      GtkClipboard *clipboard;
       
       window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
+      g_signal_connect (window, "destroy",
+                        G_CALLBACK (gtk_widget_destroyed), &window);
+
       vbox = gtk_vbox_new (FALSE, 0);
       gtk_container_set_border_width (GTK_CONTAINER (vbox), 8);
       
@@ -90,7 +226,7 @@ do_clipboard (GtkWidget *do_widget)
       button = gtk_button_new_from_stock (GTK_STOCK_COPY);
       gtk_box_pack_start (GTK_BOX (hbox), button, FALSE, FALSE, 0);
       g_signal_connect (button, "clicked",
-			G_CALLBACK (copy_button_clicked), entry);
+                        G_CALLBACK (copy_button_clicked), entry);
 
       label = gtk_label_new ("\"Paste\" will paste the text from the clipboard to the entry");
       gtk_box_pack_start (GTK_BOX (vbox), label, FALSE, FALSE, 0);
@@ -107,8 +243,70 @@ do_clipboard (GtkWidget *do_widget)
       button = gtk_button_new_from_stock (GTK_STOCK_PASTE);
       gtk_box_pack_start (GTK_BOX (hbox), button, FALSE, FALSE, 0);
       g_signal_connect (button, "clicked",
-			G_CALLBACK (paste_button_clicked), entry);
+                        G_CALLBACK (paste_button_clicked), entry);
+      
+      label = gtk_label_new ("Images can be transferred via the clipboard, too");
+      gtk_box_pack_start (GTK_BOX (vbox), label, FALSE, FALSE, 0);
+
+      hbox = gtk_hbox_new (FALSE, 4);
+      gtk_container_set_border_width (GTK_CONTAINER (hbox), 8);
+      gtk_box_pack_start (GTK_BOX (vbox), hbox, FALSE, FALSE, 0);
+
+      /* Create the first image */
+      image = gtk_image_new_from_stock (GTK_STOCK_DIALOG_WARNING, 
+                                        GTK_ICON_SIZE_BUTTON);
+      ebox = gtk_event_box_new ();
+      gtk_container_add (GTK_CONTAINER (ebox), image);
+      gtk_container_add (GTK_CONTAINER (hbox), ebox);
+
+      /* make ebox a drag source */
+      gtk_drag_source_set (ebox, GDK_BUTTON1_MASK, NULL, 0, GDK_ACTION_COPY);
+      gtk_drag_source_add_image_targets (ebox);
+      g_signal_connect (ebox, "drag_begin", 
+                        G_CALLBACK (drag_begin), image);
+      g_signal_connect (ebox, "drag_data_get", 
+                        G_CALLBACK (drag_data_get), image);
+      
+      /* accept drops on ebox */
+      gtk_drag_dest_set (ebox, GTK_DEST_DEFAULT_ALL, 
+                         NULL, 0, GDK_ACTION_COPY);
+      gtk_drag_dest_add_image_targets (ebox);
+      g_signal_connect (ebox, "drag_data_received", 
+                        G_CALLBACK (drag_data_received), image);
+      
+      /* context menu on ebox */
+      g_signal_connect (ebox, "button_press_event", 
+                        G_CALLBACK (button_press), image);
+
+      /* Create the second image */
+      image = gtk_image_new_from_stock (GTK_STOCK_STOP, 
+                                        GTK_ICON_SIZE_BUTTON);
+      ebox = gtk_event_box_new ();
+      gtk_container_add (GTK_CONTAINER (ebox), image);
+      gtk_container_add (GTK_CONTAINER (hbox), ebox);
+
+      /* make ebox a drag source */
+      gtk_drag_source_set (ebox, GDK_BUTTON1_MASK, NULL, 0, GDK_ACTION_COPY);
+      gtk_drag_source_add_image_targets (ebox);
+      g_signal_connect (ebox, "drag_begin", 
+                        G_CALLBACK (drag_begin), image);
+      g_signal_connect (ebox, "drag_data_get", 
+                        G_CALLBACK (drag_data_get), image);
+      
+      /* accept drops on ebox */
+      gtk_drag_dest_set (ebox, GTK_DEST_DEFAULT_ALL, 
+                         NULL, 0, GDK_ACTION_COPY);
+      gtk_drag_dest_add_image_targets (ebox);
+      g_signal_connect (ebox, "drag_data_received", 
+                        G_CALLBACK (drag_data_received), image);
+      
+      /* context menu on ebox */
+      g_signal_connect (ebox, "button_press_event", 
+                        G_CALLBACK (button_press), image);
       
+      /* tell the clipboard manager to make the data persistent */
+      clipboard = gtk_clipboard_get (GDK_SELECTION_CLIPBOARD);
+      gtk_clipboard_set_can_store (clipboard, NULL, 0);
     }
 
   if (!GTK_WIDGET_VISIBLE (window))