rb-tree-dnd: Rhythmbox Development Reference Manual

rb-tree-dnd

rb-tree-dnd — multi-row drag and drop support for GtkTreeViews

Functions

gboolean	rb_tree_drag_source_row_draggable ()
gboolean	rb_tree_drag_source_drag_data_delete ()
gboolean	rb_tree_drag_source_drag_data_get ()
gboolean	rb_tree_drag_dest_drag_data_received ()
gboolean	rb_tree_drag_dest_row_drop_possible ()
gboolean	rb_tree_drag_dest_row_drop_position ()
void	rb_tree_dnd_add_drag_dest_support ()
void	rb_tree_dnd_add_drag_source_support ()

Types and Values

	RbTreeDragSource
struct	RbTreeDragSourceIface
	RbTreeDragDest
struct	RbTreeDragDestIface
enum	RbTreeDestFlag

Object Hierarchy

    GInterface
    ├── RbTreeDragDest
    ╰── RbTreeDragSource

Known Implementations

RbTreeDragSource is implemented by RBDisplayPageModel, RhythmDBPropertyModel and RhythmDBQueryModel.

RbTreeDragDest is implemented by RBDisplayPageModel and RhythmDBQueryModel.

Description

Provides support for drag and drop operations to and from GtkTreeView widgets that can include multiple rows. The model backing the tree view widgets must implement the RbTreeDragSource and RbTreeDragDest interfaces.

Functions

rb_tree_drag_source_row_draggable ()

gboolean
rb_tree_drag_source_row_draggable (RbTreeDragSource *drag_source,
                                   GList *path_list);

Asks the RbTreeDragSource whether a particular row can be used as the source of a DND operation. If the source doesn't implement this interface, the row is assumed draggable.

Parameters

drag_source	a RbTreeDragSource
path_list	row on which user is initiating a drag

Returns

TRUE if the row can be dragged

rb_tree_drag_source_drag_data_delete ()

gboolean
rb_tree_drag_source_drag_data_delete (RbTreeDragSource *drag_source,
                                      GList *path_list);

Asks the RbTreeDragSource to delete the row at path , because it was moved somewhere else via drag-and-drop. Returns FALSE if the deletion fails because path no longer exists, or for some model-specific reason. Should robustly handle a path no longer found in the model!

Parameters

drag_source	a RbTreeDragSource
path_list	row that was being dragged

Returns

TRUE if the row was successfully deleted

rb_tree_drag_source_drag_data_get ()

gboolean
rb_tree_drag_source_drag_data_get (RbTreeDragSource *drag_source,
                                   GList *path_list,
                                   GtkSelectionData *selection_data);

Asks the RbTreeDragSource to fill in selection_data with a representation of the row at path . selection_data->target gives the required type of the data. Should robustly handle a path no longer found in the model!

Parameters

drag_source	a RbTreeDragSource
path_list	row that was dragged
selection_data	a GtkSelectionData to fill with data from the dragged row

Returns

TRUE if data of the required type was provided

rb_tree_drag_dest_drag_data_received ()

gboolean
rb_tree_drag_dest_drag_data_received (RbTreeDragDest *drag_dest,
                                      GtkTreePath *dest,
                                      GtkTreeViewDropPosition pos,
                                      GtkSelectionData *selection_data);

Asks a RbTreeDragDest to accept some drag and drop data.

Parameters

drag_dest	a RbTreeDragDest
dest	the GtkTreePath on which the data was dropped
pos	the drop position relative to the row identified by `dest`
selection_data	a GtkSelectionData containing the drag data

Returns

TRUE if the data was accepted, FALSE otherwise

rb_tree_drag_dest_row_drop_possible ()

gboolean
rb_tree_drag_dest_row_drop_possible (RbTreeDragDest *drag_dest,
                                     GtkTreePath *dest_path,
                                     GtkTreeViewDropPosition pos,
                                     GtkSelectionData *selection_data);

Asks the RbTreeDragDest whether data can be dropped on a particular row. This should probably check based on the format and the row.

Parameters

drag_dest	a RbTreeDragDest
dest_path	the GtkTreePath on which the data may be dropped
pos	the drop position relative to the row identified by `dest`
selection_data	a GtkSelectionData containing the drag data

Returns

TRUE if the data can be dropped there

rb_tree_drag_dest_row_drop_position ()

gboolean
rb_tree_drag_dest_row_drop_position (RbTreeDragDest *drag_dest,
                                     GtkTreePath *dest_path,
                                     GList *targets,
                                     GtkTreeViewDropPosition *pos);

Asks the RbTreeDragDest which drop position to use relative to the specified row. The drag destination should decide which drop position to use based on the target row and the list of drag targets.

Parameters

drag_dest	a RbTreeDragDest
dest_path	a GtkTreePath describing a possible drop row
targets	a GList containing possible drop target types
pos	returns the GtkTreeViewDropPosition to use relative to the row

Returns

TRUE if a drop position has been set, FALSE if a drop should not be allowed in the specified row

rb_tree_dnd_add_drag_dest_support ()

void
rb_tree_dnd_add_drag_dest_support (GtkTreeView *tree_view,
                                   RbTreeDestFlag flags,
                                   const GtkTargetEntry *targets,
                                   gint n_targets,
                                   GdkDragAction actions);

Adds event handlers to perform multi-row drag and drop operations to the specified GtkTreeView. The model backing the tree view should implement the RbTreeDragDest interface. This should be called immediately after the tree view is created.

Parameters

tree_view	a GtkTreeView that wants to be a drag destination
flags	RbTreeDestFlags for this drag destination
targets	an array of GtkTargetEntry structures describing the allowed drag targets
n_targets	the number of elements in `targets`
actions	the allowable drag actions for this destination

rb_tree_dnd_add_drag_source_support ()

void
rb_tree_dnd_add_drag_source_support (GtkTreeView *tree_view,
                                     GdkModifierType start_button_mask,
                                     const GtkTargetEntry *targets,
                                     gint n_targets,
                                     GdkDragAction actions);

Adds event handlers to perform multi-row drag and drop operations from the specified GtkTreeView widget. The model backing the GtkTreeView must implement the RbTreeDragSource interface. This should be called immediately after the tree view is created.

Parameters

tree_view	a GtkTreeView that wants to be a drag source
start_button_mask	a mask describing modifier keys to handle when dragging
targets	an array of GtkTargetEntry structures describing drag data types
n_targets	the number of elements in `targets`
actions	a mask describing drag actions that are allowed from this source

Types and Values

RbTreeDragSource

typedef struct _RbTreeDragSource RbTreeDragSource;

struct RbTreeDragSourceIface

struct RbTreeDragSourceIface {
	GTypeInterface g_iface;

	/* VTable - not signals */
	gboolean     (* rb_row_draggable)        (RbTreeDragSource   *drag_source,
	                              GList              *path_list);

	gboolean     (* rb_drag_data_get)        (RbTreeDragSource   *drag_source,
                                         GList              *path_list,
                                         GtkSelectionData   *selection_data);

	gboolean     (* rb_drag_data_delete)     (RbTreeDragSource *drag_source,
                                         GList            *path_list);
};

RbTreeDragDest

typedef struct _RbTreeDragDest RbTreeDragDest;

struct RbTreeDragDestIface

struct RbTreeDragDestIface {
	GTypeInterface g_iface;

	/* VTable - not signals */

	gboolean (* rb_drag_data_received) (RbTreeDragDest   *drag_dest,
					 GtkTreePath       *dest,
					 GtkTreeViewDropPosition pos,
					 GtkSelectionData  *selection_data);

	gboolean (* rb_row_drop_possible)  (RbTreeDragDest   *drag_dest,
					 GtkTreePath       *dest_path,
					 GtkTreeViewDropPosition pos,
					 GtkSelectionData  *selection_data);

	gboolean (* rb_row_drop_position) (RbTreeDragDest   *drag_dest,
					GtkTreePath       *dest_path,
					GList *targets,
					GtkTreeViewDropPosition *pos);

	/* optional */
	GdkAtom  (* rb_get_drag_target)    (RbTreeDragDest   *drag_dest,
					 GtkWidget        *widget,
					 GdkDragContext   *context,
					 GtkTreePath      *dest_path,
					 GtkTargetList    *target_list);
};

enum RbTreeDestFlag

Flags controlling drag destination behaviour.

Members

RB_TREE_DEST_EMPTY_VIEW_DROP	If set, drops into empty spaces in the view are accepted
RB_TREE_DEST_CAN_DROP_INTO	If set, drops into existing rows are accepted
RB_TREE_DEST_CAN_DROP_BETWEEN	If set, drops between existing rows are accepted
RB_TREE_DEST_SELECT_ON_DRAG_TIMEOUT	If set, update the drag selection using a timeout