enum GtkDestDefaults

typedef enum {
  GTK_DEST_DEFAULT_MOTION     = 1 << 0, /* respond to "drag_motion" */
  GTK_DEST_DEFAULT_HIGHLIGHT  = 1 << 1, /* auto-highlight */
  GTK_DEST_DEFAULT_DROP       = 1 << 2, /* respond to "drag_drop" */
  GTK_DEST_DEFAULT_ALL        = 0x07
} GtkDestDefaults;

The GtkDestDefaults enumeration specifies the various types of action that will be taken on behalf of the user for a drag destination site.

enum GtkTargetFlags

typedef enum {
  GTK_TARGET_SAME_APP = 1 << 0,    /*< nick=same-app >*/
  GTK_TARGET_SAME_WIDGET = 1 << 1, /*< nick=same-widget >*/
  GTK_TARGET_OTHER_APP = 1 << 2,   /*< nick=other-app >*/
  GTK_TARGET_OTHER_WIDGET = 1 << 3 /*< nick=other-widget >*/
} GtkTargetFlags;

The GtkTargetFlags enumeration is used to specify constraints on an entry in a GtkTargetTable.

gtk_drag_dest_set ()

void                gtk_drag_dest_set                   (GtkWidget *widget,
                                                         GtkDestDefaults flags,
                                                         const GtkTargetEntry *targets,
                                                         gint n_targets,
                                                         GdkDragAction actions);

Sets a widget as a potential drop destination, and adds default behaviors.

The default behaviors listed in flags have an effect similar to installing default handlers for the widget's drag-and-drop signals ("drag-motion", "drag-drop", ...). They all exist for convenience. When passing GTK_DEST_DEFAULT_ALL for instance it is sufficient to connect to the widget's "drag-data-received" signal to get primitive, but consistent drag-and-drop support.

Things become more complicated when you try to preview the dragged data, as described in the documentation for "drag-motion". The default behaviors described by flags make some assumptions, that can conflict with your own signal handlers. For instance GTK_DEST_DEFAULT_DROP causes invokations of gdk_drag_status() in the context of "drag-motion", and invokations of gtk_drag_finish() in "drag-data-received". Especially the later is dramatic, when your own "drag-motion" handler calls gtk_drag_get_data() to inspect the dragged data.

There's no way to set a default action here, you can use the "drag-motion" callback for that. Here's an example which selects the action to use depending on whether the control key is pressed or not:

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static void
drag_motion (GtkWidget *widget,
             GdkDragContext *context,
             gint x,
             gint y,
             guint time)
{
  GdkModifierType mask;

  gdk_window_get_pointer (gtk_widget_get_window (widget),
                          NULL, NULL, &mask);
  if (mask & GDK_CONTROL_MASK)
    gdk_drag_status (context, GDK_ACTION_COPY, time);
  else
    gdk_drag_status (context, GDK_ACTION_MOVE, time);
}

gtk_drag_dest_set_proxy ()

void                gtk_drag_dest_set_proxy             (GtkWidget *widget,
                                                         GdkWindow *proxy_window,
                                                         GdkDragProtocol protocol,
                                                         gboolean use_coordinates);

Set up this widget to proxy drags elsewhere.

Sets this widget as a proxy for drops to another window.

gtk_drag_dest_unset ()

void                gtk_drag_dest_unset                 (GtkWidget *widget);

Unregister this widget as a drag target.

Clears information about a drop destination set with gtk_drag_dest_set(). The widget will no longer receive notification of drags.

gtk_drag_dest_find_target ()

GdkAtom             gtk_drag_dest_find_target           (GtkWidget *widget,
                                                         GdkDragContext *context,
                                                         GtkTargetList *target_list);

Looks for a match between the supported targets of context and the dest_target_list, returning the first matching target, otherwise returning GDK_NONE. dest_target_list should usually be the return value from gtk_drag_dest_get_target_list(), but some widgets may have different valid targets for different parts of the widget; in that case, they will have to implement a drag_motion handler that passes the correct target list to this function.

gtk_drag_dest_get_target_list ()

GtkTargetList *     gtk_drag_dest_get_target_list       (GtkWidget *widget);

Returns the list of targets this widget can accept from drag-and-drop.

gtk_drag_dest_set_target_list ()

void                gtk_drag_dest_set_target_list       (GtkWidget *widget,
                                                         GtkTargetList *target_list);

Sets the target types that this widget can accept from drag-and-drop. The widget must first be made into a drag destination with gtk_drag_dest_set().

gtk_drag_dest_add_text_targets ()

void                gtk_drag_dest_add_text_targets      (GtkWidget *widget);

Add the text targets supported by GtkSelection to the target list of the drag destination. The targets are added with info = 0. If you need another value, use gtk_target_list_add_text_targets() and gtk_drag_dest_set_target_list().

Since 2.6

gtk_drag_dest_add_image_targets ()

void                gtk_drag_dest_add_image_targets     (GtkWidget *widget);

Add the image targets supported by GtkSelection to the target list of the drag destination. The targets are added with info = 0. If you need another value, use gtk_target_list_add_image_targets() and gtk_drag_dest_set_target_list().

Since 2.6

gtk_drag_dest_add_uri_targets ()

void                gtk_drag_dest_add_uri_targets       (GtkWidget *widget);

Add the URI targets supported by GtkSelection to the target list of the drag destination. The targets are added with info = 0. If you need another value, use gtk_target_list_add_uri_targets() and gtk_drag_dest_set_target_list().

Since 2.6

gtk_drag_dest_set_track_motion ()

void                gtk_drag_dest_set_track_motion      (GtkWidget *widget,
                                                         gboolean track_motion);

Tells the widget to emit ::drag-motion and ::drag-leave events regardless of the targets and the GTK_DEST_DEFAULT_MOTION flag.

This may be used when a widget wants to do generic actions regardless of the targets that the source offers.

Since 2.10

gtk_drag_dest_get_track_motion ()

gboolean            gtk_drag_dest_get_track_motion      (GtkWidget *widget);

Returns whether the widget has been configured to always emit ::drag-motion signals.

Since 2.10

gtk_drag_finish ()

void                gtk_drag_finish                     (GdkDragContext *context,
                                                         gboolean success,
                                                         gboolean del,
                                                         guint32 time_);

Informs the drag source that the drop is finished, and that the data of the drag will no longer be required.

gtk_drag_get_data ()

void                gtk_drag_get_data                   (GtkWidget *widget,
                                                         GdkDragContext *context,
                                                         GdkAtom target,
                                                         guint32 time_);

Get the data for a drag or drop

Gets the data associated with a drag. When the data is received or the retrieval fails, GTK+ will emit a "drag_data_received" signal. Failure of the retrieval is indicated by the length field of the selection_data signal parameter being negative. However, when gtk_drag_get_data() is called implicitely because the GTK_DEST_DEFAULT_DROP was set, then the widget will not receive notification of failed drops.

gtk_drag_get_source_widget ()

GtkWidget *         gtk_drag_get_source_widget          (GdkDragContext *context);

Determines the source widget for a drag.

gtk_drag_highlight ()

void                gtk_drag_highlight                  (GtkWidget *widget);

Highlight the given widget in the default manner.

Draws a highlight around a widget. This will attach handlers to "expose_event" and "draw", so the highlight will continue to be displayed until gtk_drag_unhighlight() is called.

gtk_drag_unhighlight ()

void                gtk_drag_unhighlight                (GtkWidget *widget);

Refresh the given widget to remove the highlight.

Removes a highlight set by gtk_drag_highlight() from a widget.

gtk_drag_begin ()

GdkDragContext *    gtk_drag_begin                      (GtkWidget *widget,
                                                         GtkTargetList *targets,
                                                         GdkDragAction actions,
                                                         gint button,
                                                         GdkEvent *event);

Initiates a drag on the source side. The function only needs to be used when the application is starting drags itself, and is not needed when gtk_drag_source_set() is used.

The event is used to retrieve the timestamp that will be used internally to grab the pointer. If event is NULL, then GDK_CURRENT_TIME will be used. However, you should try to pass a real event in all cases, since that can be used by GTK+ to get information about the start position of the drag, for example if the event is a GDK_MOTION_NOTIFY.

Generally there are three cases when you want to start a drag by hand by calling this function:

1. During a button-press-event handler, if you want to start a drag immediately when the user presses the mouse button. Pass the event that you have in your button-press-event handler.

2. During a motion-notify-event handler, if you want to start a drag when the mouse moves past a certain threshold distance after a button-press. Pass the event that you have in your motion-notify-event handler.

3. During a timeout handler, if you want to start a drag after the mouse button is held down for some time. Try to save the last event that you got from the mouse, using gdk_event_copy(), and pass it to this function (remember to free the event with gdk_event_free() when you are done). If you can really not pass a real event, pass NULL instead.

gtk_drag_set_icon_widget ()

void                gtk_drag_set_icon_widget            (GdkDragContext *context,
                                                         GtkWidget *widget,
                                                         gint hot_x,
                                                         gint hot_y);

Changes the icon for a widget to a given widget. GTK+ will not destroy the icon, so if you don't want it to persist, you should connect to the "drag-end" signal and destroy it yourself.

gtk_drag_set_icon_pixbuf ()

void                gtk_drag_set_icon_pixbuf            (GdkDragContext *context,
                                                         GdkPixbuf *pixbuf,
                                                         gint hot_x,
                                                         gint hot_y);

Sets pixbuf as the icon for a given drag.

gtk_drag_set_icon_stock ()

void                gtk_drag_set_icon_stock             (GdkDragContext *context,
                                                         const gchar *stock_id,
                                                         gint hot_x,
                                                         gint hot_y);

Sets the icon for a given drag from a stock ID.

gtk_drag_set_icon_surface ()

void                gtk_drag_set_icon_surface           (GdkDragContext *context,
                                                         cairo_surface_t *surface);

Sets surface as the icon for a given drag. GTK+ retains references for the arguments, and will release them when they are no longer needed.

To position the surface relative to the mouse, use cairo_surface_set_device_offset() on surface. The mouse cursor will be positioned at the (0,0) coordinate of the surface.

gtk_drag_set_icon_name ()

void                gtk_drag_set_icon_name              (GdkDragContext *context,
                                                         const gchar *icon_name,
                                                         gint hot_x,
                                                         gint hot_y);

Sets the icon for a given drag from a named themed icon. See the docs for GtkIconTheme for more details. Note that the size of the icon depends on the icon theme (the icon is loaded at the symbolic size GTK_ICON_SIZE_DND), thus hot_x and hot_y have to be used with care.

Since 2.8

gtk_drag_set_icon_default ()

void                gtk_drag_set_icon_default           (GdkDragContext *context);

Sets the icon for a particular drag to the default icon.

gtk_drag_check_threshold ()

gboolean            gtk_drag_check_threshold            (GtkWidget *widget,
                                                         gint start_x,
                                                         gint start_y,
                                                         gint current_x,
                                                         gint current_y);

Checks to see if a mouse drag starting at (start_x, start_y) and ending at (current_x, current_y) has passed the GTK+ drag threshold, and thus should trigger the beginning of a drag-and-drop operation.

gtk_drag_source_set ()

void                gtk_drag_source_set                 (GtkWidget *widget,
                                                         GdkModifierType start_button_mask,
                                                         const GtkTargetEntry *targets,
                                                         gint n_targets,
                                                         GdkDragAction actions);

Sets up a widget so that GTK+ will start a drag operation when the user clicks and drags on the widget. The widget must have a window.

gtk_drag_source_set_icon_pixbuf ()

void                gtk_drag_source_set_icon_pixbuf     (GtkWidget *widget,
                                                         GdkPixbuf *pixbuf);

Sets the icon that will be used for drags from a particular widget from a GdkPixbuf. GTK+ retains a reference for pixbuf and will release it when it is no longer needed.

gtk_drag_source_set_icon_stock ()

void                gtk_drag_source_set_icon_stock      (GtkWidget *widget,
                                                         const gchar *stock_id);

Sets the icon that will be used for drags from a particular source to a stock icon.

gtk_drag_source_set_icon_name ()

void                gtk_drag_source_set_icon_name       (GtkWidget *widget,
                                                         const gchar *icon_name);

Sets the icon that will be used for drags from a particular source to a themed icon. See the docs for GtkIconTheme for more details.

Since 2.8

gtk_drag_source_unset ()

void                gtk_drag_source_unset               (GtkWidget *widget);

Unregister this widget as a drag source.

Undoes the effects of gtk_drag_source_set().

gtk_drag_source_set_target_list ()

void                gtk_drag_source_set_target_list     (GtkWidget *widget,
                                                         GtkTargetList *target_list);

Changes the target types that this widget offers for drag-and-drop. The widget must first be made into a drag source with gtk_drag_source_set().

Since 2.4

gtk_drag_source_get_target_list ()

GtkTargetList *     gtk_drag_source_get_target_list     (GtkWidget *widget);

Gets the list of targets this widget can provide for drag-and-drop.

Since 2.4

gtk_drag_source_add_text_targets ()

void                gtk_drag_source_add_text_targets    (GtkWidget *widget);

Add the text targets supported by GtkSelection to the target list of the drag source. The targets are added with info = 0. If you need another value, use gtk_target_list_add_text_targets() and gtk_drag_source_set_target_list().

Since 2.6

gtk_drag_source_add_image_targets ()

void                gtk_drag_source_add_image_targets   (GtkWidget *widget);

Add the writable image targets supported by GtkSelection to the target list of the drag source. The targets are added with info = 0. If you need another value, use gtk_target_list_add_image_targets() and gtk_drag_source_set_target_list().

Since 2.6

gtk_drag_source_add_uri_targets ()

void                gtk_drag_source_add_uri_targets     (GtkWidget *widget);

Add the URI targets supported by GtkSelection to the target list of the drag source. The targets are added with info = 0. If you need another value, use gtk_target_list_add_uri_targets() and gtk_drag_source_set_target_list().

Since 2.6