Activatable widgets can be connected to a gtk.Action and reflects the state of its action. A GtkActivatable can also provide feedback through its action, as they are responsible for activating their related actions.

Implementing GtkActivatable

When extending a class that is already GtkActivatable; it is only necessary to implement the [GtkActivatable-|GtkActivatable-]>Action.properties and [GtkActivatable-|GtkActivatable-]>update() methods and chain up to the parent implementation, however when introducing a new GtkActivatable class; the related-action and use-action-appearance properties need to be handled by the implementor. Handling these properties is mostly a matter of installing the action pointer and boolean flag on your instance, and calling gtk_activatable_do_set_related_action() and gtk_activatable_sync_action_properties() at the appropriate times.

A class fragment implementing GtkActivatable

1 
2 
3 enum {
4 ...
5 
6 PROP_ACTIVATABLE_RELATED_ACTION,
7 PROP_ACTIVATABLE_USE_ACTION_APPEARANCE
8 }
9 
10 struct _FooBarPrivate
11 {
12 
13 ...
14 
15 GtkAction      *action;
16 gboolean        use_action_appearance;
17 };
18 
19 ...
20 
21 static void foo_bar_activatable_interface_init         (GtkActivatableIface  *iface);
22 static void foo_bar_activatable_update                 (GtkActivatable       *activatable,
23 GtkAction            *action,
24 const gchar          *property_name);
25 static void foo_bar_activatable_sync_action_properties (GtkActivatable       *activatable,
26 GtkAction            *action);
27 ...
28 
29 
30 static void
31 foo_bar_class_init (FooBarClass *klass)
32 {
33 
34 ...
35 
36 g_object_class_override_property (gobject_class, PROP_ACTIVATABLE_RELATED_ACTION, "related-action");
37 g_object_class_override_property (gobject_class, PROP_ACTIVATABLE_USE_ACTION_APPEARANCE, "use-action-appearance");
38 
39 ...
40 }
41 
42 
43 static void
44 foo_bar_activatable_interface_init (GtkActivatableIface  *iface)
45 {
46 iface->update = foo_bar_activatable_update;
47 iface->sync_action_properties = foo_bar_activatable_sync_action_properties;
48 }
49 
50 ... Break the reference using `gtk_activatable_do_set_related_action()`...
51 
52 static void
53 foo_bar_dispose (GObject *object)
54 {
55 FooBar *bar = FOO_BAR (object);
56 FooBarPrivate *priv = FOO_BAR_GET_PRIVATE (bar);
57 
58 ...
59 
60 if (priv->action)
61 {
62 gtk_activatable_do_set_related_action (GTK_ACTIVATABLE (bar), NULL);
63 priv->action = NULL;
64 }
65 G_OBJECT_CLASS (foo_bar_parent_class)->dispose (object);
66 }
67 
68 ... Handle the “related-action” and “use-action-appearance” properties ...
69 
70 static void
71 foo_bar_set_property (GObject         *object,
72 guint            prop_id,
73 const GValue    *value,
74 GParamSpec      *pspec)
75 {
76 FooBar *bar = FOO_BAR (object);
77 FooBarPrivate *priv = FOO_BAR_GET_PRIVATE (bar);
78 
79 switch (prop_id)
80 {
81 
82 ...
83 
84 case PROP_ACTIVATABLE_RELATED_ACTION:
85 foo_bar_set_related_action (bar, g_value_get_object (value));
86 break;
87 case PROP_ACTIVATABLE_USE_ACTION_APPEARANCE:
88 foo_bar_set_use_action_appearance (bar, g_value_get_boolean (value));
89 break;
90 default:
91 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
92 break;
93 }
94 }
95 
96 static void
97 foo_bar_get_property (GObject         *object,
98 guint            prop_id,
99 GValue          *value,
100 GParamSpec      *pspec)
101 {
102 FooBar *bar = FOO_BAR (object);
103 FooBarPrivate *priv = FOO_BAR_GET_PRIVATE (bar);
104 
105 switch (prop_id)
106 {
107 
108 ...
109 
110 case PROP_ACTIVATABLE_RELATED_ACTION:
111 g_value_set_object (value, priv->action);
112 break;
113 case PROP_ACTIVATABLE_USE_ACTION_APPEARANCE:
114 g_value_set_boolean (value, priv->use_action_appearance);
115 break;
116 default:
117 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
118 break;
119 }
120 }
121 
122 
123 static void
124 foo_bar_set_use_action_appearance (FooBar   *bar,
125 gboolean  use_appearance)
126 {
127 FooBarPrivate *priv = FOO_BAR_GET_PRIVATE (bar);
128 
129 if (priv->use_action_appearance != use_appearance)
130 {
131 priv->use_action_appearance = use_appearance;
132 
133 gtk_activatable_sync_action_properties (GTK_ACTIVATABLE (bar), priv->action);
134 }
135 }
136 
137 ... call `gtk_activatable_do_set_related_action()` and then assign the action pointer,
138 no need to reference the action here since `gtk_activatable_do_set_related_action()` already
139 holds a reference here for you...
140 static void
141 foo_bar_set_related_action (FooBar    *bar,
142 GtkAction *action)
143 {
144 FooBarPrivate *priv = FOO_BAR_GET_PRIVATE (bar);
145 
146 if (priv->action == action)
147 return;
148 
149 gtk_activatable_do_set_related_action (GTK_ACTIVATABLE (bar), action);
150 
151 priv->action = action;
152 }
153 
154 ... Selectively reset and update activatable depending on the use-action-appearance property ...
155 static void
156 gtk_button_activatable_sync_action_properties (GtkActivatable       *activatable,
157 GtkAction            *action)
158 {
159 GtkButtonPrivate *priv = GTK_BUTTON_GET_PRIVATE (activatable);
160 
161 if (!action)
162 return;
163 
164 if (gtk_action_is_visible (action))
165 gtk_widget_show (GTK_WIDGET (activatable));
166 else
167 gtk_widget_hide (GTK_WIDGET (activatable));
168 
169 gtk_widget_set_sensitive (GTK_WIDGET (activatable), gtk_action_is_sensitive (action));
170 
171 ...
172 
173 if (priv->use_action_appearance)
174 {
175 if (gtk_action_get_stock_id (action))
176 foo_bar_set_stock (button, gtk_action_get_stock_id (action));
177 else if (gtk_action_get_label (action))
178 foo_bar_set_label (button, gtk_action_get_label (action));
179 
180 ...
181 
182 }
183 }
184 
185 static void
186 foo_bar_activatable_update (GtkActivatable       *activatable,
187 GtkAction            *action,
188 const gchar          *property_name)
189 {
190 FooBarPrivate *priv = FOO_BAR_GET_PRIVATE (activatable);
191 
192 if (strcmp (property_name, "visible") == 0)
193 {
194 if (gtk_action_is_visible (action))
195 gtk_widget_show (GTK_WIDGET (activatable));
196 else
197 gtk_widget_hide (GTK_WIDGET (activatable));
198 }
199 else if (strcmp (property_name, "sensitive") == 0)
200 gtk_widget_set_sensitive (GTK_WIDGET (activatable), gtk_action_is_sensitive (action));
201 
202 ...
203 
204 if (!priv->use_action_appearance)
205 return;
206 
207 if (strcmp (property_name, "stock-id") == 0)
208 foo_bar_set_stock (button, gtk_action_get_stock_id (action));
209 else if (strcmp (property_name, "label") == 0)
210 foo_bar_set_label (button, gtk_action_get_label (action));
211 
212 ...
213 }