GtkPadController: GTK+ 3 Reference Manual

GtkPadController

GtkPadController — Controller for drawing tablet pads

Functions

GtkPadController *	gtk_pad_controller_new ()
void	gtk_pad_controller_set_action_entries ()
void	gtk_pad_controller_set_action ()

Properties

GActionGroup *	action-group	Read / Write / Construct Only
GdkDevice *	pad	Read / Write / Construct Only

Types and Values

	GtkPadController
enum	GtkPadActionType
struct	GtkPadActionEntry

Object Hierarchy

    GObject
    ╰── GtkEventController
        ╰── GtkPadController

Includes

#include <gtk/gtk.h>

Description

GtkPadController is an event controller for the pads found in drawing tablets (The collection of buttons and tactile sensors often found around the stylus-sensitive area).

These buttons and sensors have no implicit meaning, and by default they perform no action, this event controller is provided to map those to GAction objects, thus letting the application give those a more semantic meaning.

Buttons and sensors are not constrained to triggering a single action, some GDK_SOURCE_TABLET_PAD devices feature multiple "modes", all these input elements have one current mode, which may determine the final action being triggered. Pad devices often divide buttons and sensors into groups, all elements in a group share the same current mode, but different groups may have different modes. See gdk_device_pad_get_n_groups() and gdk_device_pad_get_group_n_modes().

Each of the actions that a given button/strip/ring performs for a given mode is defined by GtkPadActionEntry, it contains an action name that will be looked up in the given GActionGroup and activated whenever the specified input element and mode are triggered.

A simple example of GtkPadController usage, assigning button 1 in all modes and pad devices to an "invert-selection" action:

GtkPadActionEntry *pad_actions[] = {
  { GTK_PAD_ACTION_BUTTON, 1, -1, "Invert selection", "pad-actions.invert-selection" },
  …
};

…
action_group = g_simple_action_group_new ();
action = g_simple_action_new ("pad-actions.invert-selection", NULL);
g_signal_connect (action, "activate", on_invert_selection_activated, NULL);
g_action_map_add_action (G_ACTION_MAP (action_group), action);
…
pad_controller = gtk_pad_controller_new (window, action_group, NULL);

The actions belonging to rings/strips will be activated with a parameter of type G_VARIANT_TYPE_DOUBLE bearing the value of the given axis, it is required that those are made stateful and accepting this GVariantType.

Functions

gtk_pad_controller_new ()

GtkPadController *
gtk_pad_controller_new (GtkWindow *window,
                        GActionGroup *group,
                        GdkDevice *pad);

Creates a new GtkPadController that will associate events from pad to actions. A NULL pad may be provided so the controller manages all pad devices generically, it is discouraged to mix GtkPadController objects with NULL and non-NULL pad argument on the same window , as execution order is not guaranteed.

The GtkPadController is created with no mapped actions. In order to map pad events to actions, use gtk_pad_controller_set_action_entries() or gtk_pad_controller_set_action().

Parameters

window	a GtkWindow
group	GActionGroup to trigger actions from
pad	A `GDK_SOURCE_TABLET_PAD` device, or `NULL` to handle all pads.	[nullable]

Returns

A newly created GtkPadController

Since: 3.22

gtk_pad_controller_set_action_entries ()

void
gtk_pad_controller_set_action_entries (GtkPadController *controller,
                                       const GtkPadActionEntry *entries,
                                       gint n_entries);

This is a convenience function to add a group of action entries on controller . See GtkPadActionEntry and gtk_pad_controller_set_action().

Parameters

controller	a GtkPadController
entries	the action entries to set on `controller` .	[array length=n_entries]
n_entries	the number of elements in `entries`

Since: 3.22

gtk_pad_controller_set_action ()

void
gtk_pad_controller_set_action (GtkPadController *controller,
                               GtkPadActionType type,
                               gint index,
                               gint mode,
                               const gchar *label,
                               const gchar *action_name);

Adds an individual action to controller . This action will only be activated if the given button/ring/strip number in index is interacted while the current mode is mode . -1 may be used for simple cases, so the action is triggered on all modes.

The given label should be considered user-visible, so internationalization rules apply. Some windowing systems may be able to use those for user feedback.

Parameters

controller	a GtkPadController
type	the type of pad feature that will trigger this action
index	the 0-indexed button/ring/strip number that will trigger this action
mode	the mode that will trigger this action, or -1 for all modes.
label	Human readable description of this action, this string should be deemed user-visible.
action_name	action name that will be activated in the GActionGroup

Since: 3.22

Types and Values