/* Find drop target at position */
static XfdashboardDropAction* _xfdashboard_drag_action_find_drop_traget_at_coord(XfdashboardDragAction *self,
gfloat inStageX,
gfloat inStageY)
{
XfdashboardDragActionPrivate *priv;
GSList *list;
g_return_val_if_fail(XFDASHBOARD_IS_DRAG_ACTION(self), NULL);
priv=self->priv;
/* Iterate through list and return first drop target in list
* where coordinates fit in
*/
for(list=priv->targets; list; list=g_slist_next(list))
{
ClutterActorMeta *actorMeta=CLUTTER_ACTOR_META(list->data);
ClutterActor *actor=clutter_actor_meta_get_actor(actorMeta);
gfloat x, y, w, h;
/* Get position and size of actor in stage coordinates */
clutter_actor_get_transformed_position(actor, &x, &y);
clutter_actor_get_transformed_size(actor, &w, &h);
/* If given stage coordinates fit in actor we found it */
if(inStageX>=x && inStageX<(x+w) &&
inStageY>=y && inStageY<(y+h))
{
return(XFDASHBOARD_DROP_ACTION(actorMeta));
}
}
/* If we get here no drop target was found */
return(NULL);
}
/* Called when attaching and detaching a ClutterActorMeta instance to a ClutterActor */
static void _xfdashboard_drop_action_set_actor(ClutterActorMeta *inActorMeta, ClutterActor *inActor)
{
XfdashboardDropAction *self;
XfdashboardDropActionPrivate *priv;
g_return_if_fail(XFDASHBOARD_IS_DROP_ACTION(inActorMeta));
g_return_if_fail(inActor==NULL || CLUTTER_IS_ACTOR(inActor));
self=XFDASHBOARD_DROP_ACTION(inActorMeta);
priv=self->priv;
/* Unregister current drop target */
if(priv->actor)
{
/* Disconnect signals */
if(priv->destroySignalID) g_signal_handler_disconnect(priv->actor, priv->destroySignalID);
/* Unset style */
if(XFDASHBOARD_IS_ACTOR(priv->actor))
{
xfdashboard_stylable_remove_pseudo_class(XFDASHBOARD_STYLABLE(priv->actor), "drop-target");
}
/* Unregister drop target */
_xfdashboard_drop_action_unregister_target(self);
priv->destroySignalID=0;
priv->actor=NULL;
}
/* Register new drop target */
if(inActor)
{
priv->actor=inActor;
/* Register drop target */
_xfdashboard_drop_action_register_target(self);
/* Connect signals */
priv->destroySignalID=g_signal_connect_swapped(priv->actor,
"destroy",
G_CALLBACK(_xfdashboard_drop_action_on_target_actor_destroy),
self);
}
/* Call parent's class method */
CLUTTER_ACTOR_META_CLASS(xfdashboard_drop_action_parent_class)->set_actor(inActorMeta, inActor);
}
/* Dragging of actor ended */
static void _xfdashboard_drag_action_drag_end(ClutterDragAction *inAction,
ClutterActor *inActor,
gfloat inStageX,
gfloat inStageY,
ClutterModifierType inModifiers)
{
XfdashboardDragAction *self;
XfdashboardDragActionPrivate *priv;
ClutterDragActionClass *dragActionClass;
GSList *list;
XfdashboardDropAction *dropTarget;
gfloat dropX, dropY;
gboolean canDrop;
g_return_if_fail(XFDASHBOARD_IS_DRAG_ACTION(inAction));
self=XFDASHBOARD_DRAG_ACTION(inAction);
priv=self->priv;
dragActionClass=CLUTTER_DRAG_ACTION_CLASS(xfdashboard_drag_action_parent_class);
canDrop=FALSE;
dropTarget=NULL;
/* Hold a reference on ourselve as ClutterAction as the actor where we are bound to
* may be destroyed in this function. We need to keep alive this action until
* function ends.
*/
g_object_ref(self);
/* Unset styles */
if(priv->source && XFDASHBOARD_IS_ACTOR(priv->source))
{
xfdashboard_stylable_remove_pseudo_class(XFDASHBOARD_STYLABLE(priv->source), "drag-source");
}
if(XFDASHBOARD_IS_ACTOR(priv->actor))
{
xfdashboard_stylable_remove_pseudo_class(XFDASHBOARD_STYLABLE(priv->actor), "dragged");
}
if(priv->dragHandle &&
XFDASHBOARD_IS_ACTOR(priv->dragHandle))
{
gchar *styleClass;
if(priv->source)
{
styleClass=g_strdup_printf("drag-source-%s", G_OBJECT_TYPE_NAME(priv->source));
xfdashboard_stylable_remove_class(XFDASHBOARD_STYLABLE(priv->dragHandle), styleClass);
g_free(styleClass);
}
styleClass=g_strdup_printf("drag-actor-%s", G_OBJECT_TYPE_NAME(priv->actor));
xfdashboard_stylable_remove_class(XFDASHBOARD_STYLABLE(priv->dragHandle), styleClass);
g_free(styleClass);
xfdashboard_stylable_remove_pseudo_class(XFDASHBOARD_STYLABLE(priv->dragHandle), "drag-handle");
priv->dragHandle=NULL;
}
if(priv->dragHandleChangedID)
{
g_signal_handler_disconnect(self, priv->dragHandleChangedID);
priv->dragHandleChangedID=0;
}
/* Remove 'destroy' signal on dragged actor */
if(priv->actorDestroySignalID)
{
g_signal_handler_disconnect(priv->actor, priv->actorDestroySignalID);
priv->actorDestroySignalID=0;
}
/* Remove our listerners for allocation changes */
for(list=priv->targets; list; list=g_slist_next(list))
{
XfdashboardDropAction *target=XFDASHBOARD_DROP_ACTION(list->data);
ClutterActorMeta *actorMeta=CLUTTER_ACTOR_META(target);
ClutterActor *actor=clutter_actor_meta_get_actor(actorMeta);
g_signal_handlers_disconnect_by_func(actor, G_CALLBACK(_xfdashboard_drag_on_drop_target_allocation_changed), self);
}
/* Find drop target at stage coordinate if dragged actor was not destroyed */
if(!priv->dragCancelled) dropTarget=_xfdashboard_drag_action_find_drop_traget_at_coord(self, inStageX, inStageY);
/* If drop target was found check if we are allowed to drop on it. */
if(dropTarget)
{
/* Transform event coordinates relative to drop target */
_xfdashboard_drag_action_transform_stage_point(dropTarget,
inStageX, inStageY,
&dropX, &dropY);
/* Ask drop target if we are allowed to drop dragged actor on it */
g_signal_emit_by_name(dropTarget, "can-drop", self, dropX, dropY, &canDrop);
}
/* If we cannot drop the draggged actor emit "drag-cancel" on dragged actor */
if(!canDrop) g_signal_emit_by_name(inAction, "drag-cancel", priv->actor, inStageX, inStageY, NULL);
/* Iterate through list of drop targets to emit the "end" signal to the ones
* on which the dragged actor will not be drop (either they were not the target
* or it did not allow to drop on it). The real drop target gets the "drop"
* signal.
*/
for(list=priv->targets; list; list=g_slist_next(list))
{
XfdashboardDropAction *target=XFDASHBOARD_DROP_ACTION(list->data);
if(canDrop && target && target==dropTarget)
{
g_signal_emit_by_name(dropTarget, "drop", self, dropX, dropY, NULL);
}
else
{
g_signal_emit_by_name(target, "end", self, NULL);
}
}
/* Call parent's class method at last */
if(dragActionClass->drag_end) dragActionClass->drag_end(inAction, inActor, inStageX, inStageY, inModifiers);
/* Forget dragged actor as dragging has ended now */
priv->actor=NULL;
/* Free list of drop targets and unref each drop target */
if(priv->targets) g_slist_free_full(priv->targets, g_object_unref);
priv->targets=NULL;
/* Free list of actor we crossed by motion */
if(priv->lastMotionActors)
{
g_slist_foreach(priv->lastMotionActors, _xfdashboard_drag_action_on_motion_actor_destroyed, self);
if(priv->lastMotionActors) g_slist_free(priv->lastMotionActors);
priv->lastMotionActors=NULL;
}
/* Reset variables */
priv->lastDropTarget=NULL;
/* Release the reference we took at function beginning */
g_object_unref(self);
}
/* Dragging of actor begins */
static void _xfdashboard_drag_action_drag_begin(ClutterDragAction *inAction,
ClutterActor *inActor,
gfloat inStageX,
gfloat inStageY,
ClutterModifierType inModifiers)
{
XfdashboardDragAction *self;
XfdashboardDragActionPrivate *priv;
ClutterDragActionClass *dragActionClass;
GSList *list;
g_return_if_fail(XFDASHBOARD_IS_DRAG_ACTION(inAction));
self=XFDASHBOARD_DRAG_ACTION(inAction);
priv=self->priv;
dragActionClass=CLUTTER_DRAG_ACTION_CLASS(xfdashboard_drag_action_parent_class);
/* Call parent's class method */
if(dragActionClass->drag_begin) dragActionClass->drag_begin(inAction, inActor, inStageX, inStageY, inModifiers);
/* Remember dragged actor while dragging and listen to possible 'destroy' signal emissions */
priv->actor=inActor;
priv->actorDestroySignalID=g_signal_connect_swapped(priv->actor, "destroy", G_CALLBACK(_xfdashboard_drag_action_on_dragged_actor_destroyed), self);
/* Get list of drop targets. It is a new list with all current
* drop targets already reffed. So the drop targets will be valid
* while dragging
*/
priv->targets=xfdashboard_drop_action_get_targets();
/* Emit "begin" signal on all drop targets to determine if they
* can handle dragged actor and to prepare them for dragging.
* All targets returning TRUE (and therefore telling us they
* can handle dragged actor and are prepared for drag'n'drop)
* will be sorted.
*/
list=priv->targets;
while(list)
{
XfdashboardDropAction *dropTarget=XFDASHBOARD_DROP_ACTION(list->data);
gboolean canHandle=FALSE;
g_signal_emit_by_name(dropTarget, "begin", self, &canHandle);
if(!canHandle)
{
GSList *next;
/* Drop target cannot handle dragged actor so unref it and
* remove it from list of drop targets
*/
next=g_slist_next(list);
priv->targets=g_slist_remove_link(priv->targets, list);
g_object_unref(list->data);
g_slist_free_1(list);
list=next;
}
else list=g_slist_next(list);
}
_xfdashboard_drag_action_sort_targets(self);
/* We should listen to allocation changes for each actor which
* is an active drop target.
*/
for(list=priv->targets; list; list=g_slist_next(list))
{
XfdashboardDropAction *dropTarget=XFDASHBOARD_DROP_ACTION(list->data);
ClutterActorMeta *actorMeta=CLUTTER_ACTOR_META(dropTarget);
ClutterActor *actor=clutter_actor_meta_get_actor(actorMeta);
g_signal_connect_swapped(actor, "allocation-changed", G_CALLBACK(_xfdashboard_drag_on_drop_target_allocation_changed), self);
}
/* Setup for dragging */
priv->dragCancelled=FALSE;
priv->lastDropTarget=NULL;
priv->lastMotionActors=NULL;
/* Set styles */
if(priv->source && XFDASHBOARD_IS_ACTOR(priv->source))
{
xfdashboard_stylable_add_pseudo_class(XFDASHBOARD_STYLABLE(priv->source), "drag-source");
}
if(XFDASHBOARD_IS_ACTOR(priv->actor))
{
xfdashboard_stylable_add_pseudo_class(XFDASHBOARD_STYLABLE(priv->actor), "dragged");
}
priv->dragHandle=clutter_drag_action_get_drag_handle(CLUTTER_DRAG_ACTION(self));
if(priv->dragHandle &&
XFDASHBOARD_IS_ACTOR(priv->dragHandle))
{
gchar *styleClass;
if(priv->source)
{
styleClass=g_strdup_printf("drag-source-%s", G_OBJECT_TYPE_NAME(priv->source));
xfdashboard_stylable_add_class(XFDASHBOARD_STYLABLE(priv->dragHandle), styleClass);
g_free(styleClass);
}
styleClass=g_strdup_printf("drag-actor-%s", G_OBJECT_TYPE_NAME(priv->actor));
xfdashboard_stylable_add_class(XFDASHBOARD_STYLABLE(priv->dragHandle), styleClass);
g_free(styleClass);
xfdashboard_stylable_add_pseudo_class(XFDASHBOARD_STYLABLE(priv->dragHandle), "drag-handle");
/* Get notified if drag handle changes */
priv->dragHandleChangedID=g_signal_connect(self, "notify::drag-handle", G_CALLBACK(_xfdashboard_drag_action_on_drag_handle_changed), NULL);
}
}
