Change signatures for gdk_drag_begin() and gdk_drag_motion() so that the

Wed Jan 27 18:57:57 1999  Owen Taylor  <otaylor@redhat.com>

	* gdk/gdk.h gdk/gdkdnd.c: Change signatures for
	gdk_drag_begin() and gdk_drag_motion() so that the set
	of possible actions is passed on each motion, not just at
	the beginning of the drag. We do this so that
	we can restrict the set of possible drag events
	when the user presses a modifier key during a
	drag.

	* gdk/gdkdnd.c: Send a motif Operation-changed
	message when the set of possible actions change,
	as well as when the suggested action change.

	* gdk/gdkdnd.c: Change the XdndActionList whenever
	the set of actions change.

	* gdk/gdkdnd.c: Add a filter to catch changes to
	the XdndActionList property for the source widget.

	* gtk/gtkdnd.c: Change the set of possible actions
	when the user presses Control, Shift, or Control-Shift,
	to only include the corresponding action.

	* gtk/gtkdnd.c (gtk_drag_button_release_cb):
	Disconnect button signals before we possibly
	free info structure.

1 files changed, 79 insertions, 38 deletions

diff --git a/gtk/gtkdnd.c b/gtk/gtkdnd.c
index 1c5efd714e..8ffdd2abf0 100644
--- a/gtk/gtkdnd.c
+++ b/gtk/gtkdnd.c
@@ -58,6 +58,7 @@ struct _GtkDragSourceSite {
 struct _GtkDragSourceInfo {
   GtkWidget         *widget;
   GtkTargetList     *target_list; /* Targets for drag data */
+  GdkDragAction      possible_actions; /* Actions allowed by source */
   GdkDragContext    *context;	  /* drag context */
   GtkWidget         *icon_window; /* Window for drag */
   GtkWidget         *ipc_widget;  /* GtkInvisible for grab, message passing */
@@ -145,9 +146,11 @@ static gint         default_icon_hot_x;
 static gint         default_icon_hot_y;
 
 /* Forward declarations */
-static GdkDragAction gtk_drag_get_event_action   (GdkEvent        *event, 
-						  gint             button,
-						  GdkDragAction    actions);
+static void gtk_drag_get_event_actions   (GdkEvent        *event, 
+					  gint             button,
+					  GdkDragAction    actions,
+					  GdkDragAction   *suggested_action,
+					  GdkDragAction   *possible_actions);
 static GdkCursor *   gtk_drag_get_cursor         (GdkDragAction action);
 static GtkWidget    *gtk_drag_get_ipc_widget     (void);
 static void          gtk_drag_release_ipc_widget (GtkWidget *widget);
@@ -391,9 +394,16 @@ gtk_drag_release_ipc_widget (GtkWidget *widget)
   drag_widgets = g_slist_prepend (drag_widgets, widget);
 }
 
-static GdkDragAction
-gtk_drag_get_event_action (GdkEvent *event, gint button, GdkDragAction actions)
+static void
+gtk_drag_get_event_actions (GdkEvent *event, 
+			    gint button, 
+			    GdkDragAction  actions,
+			    GdkDragAction *suggested_action,
+			    GdkDragAction *possible_actions)
 {
+  *suggested_action = 0;
+  *possible_actions = 0;
+
   if (event)
     {
       GdkModifierType state = 0;
@@ -422,32 +432,55 @@ gtk_drag_get_event_action (GdkEvent *event, gint button, GdkDragAction actions)
       }
       
       if (((button == 2) || (button == 3)) && (actions & GDK_ACTION_ASK))
-	return GDK_ACTION_ASK;
-      
-      if (state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK))
+	{
+	  *suggested_action = GDK_ACTION_ASK;
+	  *possible_actions = actions;
+	}
+      else if (state & (GDK_SHIFT_MASK | GDK_CONTROL_MASK))
 	{
 	  if ((state & GDK_SHIFT_MASK) && (state & GDK_CONTROL_MASK))
-	    return (actions & GDK_ACTION_LINK) ? GDK_ACTION_LINK : 0;
+	    {
+	      if (actions & GDK_ACTION_LINK)
+		{
+		  *suggested_action = GDK_ACTION_LINK;
+		  *possible_actions = GDK_ACTION_LINK;
+		}
+	    }
 	  else if (state & GDK_CONTROL_MASK)
-	    return (actions & GDK_ACTION_COPY) ? GDK_ACTION_COPY : 0;
+	    {
+	      if (actions & GDK_ACTION_COPY)
+		{
+		  *suggested_action = GDK_ACTION_COPY;
+		  *possible_actions = GDK_ACTION_COPY;
+		}
+	      return;
+	    }
 	  else
-	    return (actions & GDK_ACTION_MOVE) ? GDK_ACTION_MOVE : 0;
+	    {
+	      if (actions & GDK_ACTION_MOVE)
+		{
+		  *suggested_action = GDK_ACTION_MOVE;
+		  *possible_actions = GDK_ACTION_MOVE;
+		}
+	      return;
+	    }
 	}
       else
 	{
-	  if ((state & (GDK_MOD1_MASK)) && (actions & GDK_ACTION_ASK))
-	    return GDK_ACTION_ASK;
+	  *possible_actions = actions;
 
-	  if (actions & GDK_ACTION_COPY)
-	    return GDK_ACTION_COPY;
+	  if ((state & (GDK_MOD1_MASK)) && (actions & GDK_ACTION_ASK))
+	    *suggested_action = GDK_ACTION_ASK;
+	  else if (actions & GDK_ACTION_COPY)
+	    *suggested_action =  GDK_ACTION_COPY;
 	  else if (actions & GDK_ACTION_MOVE)
-	    return GDK_ACTION_MOVE;
+	    *suggested_action = GDK_ACTION_MOVE;
 	  else if (actions & GDK_ACTION_LINK)
-	    return GDK_ACTION_LINK;
+	    *suggested_action = GDK_ACTION_LINK;
 	}
     }
   
-  return 0;
+  return;
 }
 
 static GdkCursor *
@@ -1164,8 +1197,7 @@ gtk_drag_proxy_begin (GtkWidget *widget, GtkDragDestInfo *dest_info)
   source_info->widget = widget;
   gtk_widget_ref (source_info->widget);
   source_info->context = gdk_drag_begin (source_info->ipc_widget->window,
-					 dest_info->context->targets, 
-					 dest_info->context->actions);
+					 dest_info->context->targets);
 
   source_info->target_list = gtk_target_list_new (NULL, 0);
   tmp_list = dest_info->context->targets;
@@ -1295,7 +1327,8 @@ gtk_drag_dest_motion (GtkWidget	     *widget,
 		       dest_window, proto,
 		       current_event->dnd.x_root, 
 		       current_event->dnd.y_root, 
-		       context->suggested_action, time);
+		       context->suggested_action, 
+		       context->actions, time);
 
       selection = gdk_drag_get_selection (info->proxy_source->context);
       if (selection && 
@@ -1411,7 +1444,8 @@ gtk_drag_dest_drop (GtkWidget	     *widget,
 			   dest_window, proto,
 			   current_event->dnd.x_root, 
 			   current_event->dnd.y_root, 
-			   context->suggested_action, time);
+			   context->suggested_action, 
+			   context->actions, time);
 
 	  selection = gdk_drag_get_selection (info->proxy_source->context);
 	  if (selection && 
@@ -1472,6 +1506,7 @@ gtk_drag_begin (GtkWidget         *widget,
   GList *targets = NULL;
   GList *tmp_list;
   guint32 time = GDK_CURRENT_TIME;
+  GdkDragAction possible_actions, suggested_action;
 
   g_return_val_if_fail (widget != NULL, NULL);
   g_return_val_if_fail (GTK_WIDGET_REALIZED (widget), NULL);
@@ -1498,8 +1533,7 @@ gtk_drag_begin (GtkWidget         *widget,
   info->widget = widget;
   gtk_widget_ref (info->widget);
   
-  info->context = gdk_drag_begin (info->ipc_widget->window,
-				  targets, actions);
+  info->context = gdk_drag_begin (info->ipc_widget->window, targets);
   g_list_free (targets);
   
   g_dataset_set_data (info->context, "gtk-info", info);
@@ -1508,15 +1542,19 @@ gtk_drag_begin (GtkWidget         *widget,
   info->target_list = target_list;
   gtk_target_list_ref (target_list);
 
+  info->possible_actions = actions;
+
   info->cursor = NULL;
   info->status = GTK_DRAG_STATUS_DRAG;
   info->last_event = NULL;
   info->selections = NULL;
   info->icon_window = NULL;
+
+  gtk_drag_get_event_actions (event, info->button, actions,
+			      &suggested_action, &possible_actions);
   
   if (event)
-    info->cursor = gtk_drag_get_cursor (
-	    gtk_drag_get_event_action (event, info->button, 0));
+    info->cursor = gtk_drag_get_cursor (suggested_action);
 
   gtk_signal_emit_by_name (GTK_OBJECT (widget), "drag_begin",
 			   info->context);
@@ -2371,6 +2409,7 @@ gtk_drag_motion_cb (GtkWidget      *widget,
   GtkDragSourceInfo *info = (GtkDragSourceInfo *)data;
   GdkAtom selection;
   GdkDragAction action;
+  GdkDragAction possible_actions;
   GdkWindow *window = NULL;
   GdkWindow *dest_window;
   GdkDragProtocol protocol;
@@ -2383,9 +2422,10 @@ gtk_drag_motion_cb (GtkWidget      *widget,
       event->y_root = y_root;
     }
 
-  action = gtk_drag_get_event_action ((GdkEvent *)event, 
-				      info->button, 
-				      info->context->actions);
+  gtk_drag_get_event_actions ((GdkEvent *)event, 
+			      info->button, 
+			      info->possible_actions,
+			      &action, &possible_actions);
   
   info->cur_x = event->x_root - info->hot_x;
   info->cur_y = event->y_root - info->hot_y;
@@ -2402,7 +2442,8 @@ gtk_drag_motion_cb (GtkWidget      *widget,
 			&dest_window, &protocol);
 
   if (gdk_drag_motion (info->context, dest_window, protocol,
-		       event->x_root, event->y_root, action,
+		       event->x_root, event->y_root, action, 
+		       possible_actions,
 		       event->time))
     {
       if (info->last_event)
@@ -2452,6 +2493,14 @@ gtk_drag_button_release_cb (GtkWidget      *widget,
 
   gdk_pointer_ungrab (event->time);
 
+  gtk_grab_remove (widget);
+  gtk_signal_disconnect_by_func (GTK_OBJECT (widget), 
+				 GTK_SIGNAL_FUNC (gtk_drag_button_release_cb),
+				 info);
+  gtk_signal_disconnect_by_func (GTK_OBJECT (widget), 
+				 GTK_SIGNAL_FUNC (gtk_drag_motion_cb),
+				 info);
+
   if ((info->context->action != 0) && (info->context->dest_window != NULL))
     {
       gtk_drag_drop (info, event->time);
@@ -2462,14 +2511,6 @@ gtk_drag_button_release_cb (GtkWidget      *widget,
       gtk_drag_drop_finished (info, FALSE, event->time);
     }
 
-  gtk_grab_remove (widget);
-  gtk_signal_disconnect_by_func (GTK_OBJECT (widget), 
-				 GTK_SIGNAL_FUNC (gtk_drag_button_release_cb),
-				 info);
-  gtk_signal_disconnect_by_func (GTK_OBJECT (widget), 
-				 GTK_SIGNAL_FUNC (gtk_drag_motion_cb),
-				 info);
-
   /* Send on a release pair to the the original 
    * widget to convince it to release its grab. We need to
    * call gtk_propagate_event() here, instead of