--- a/libmlk-ui/mlk/ui/checkbox.h	Fri Aug 11 19:22:00 2023 +0200
+++ b/libmlk-ui/mlk/ui/checkbox.h	Fri Aug 11 12:58:02 2023 +0200
@@ -19,49 +19,181 @@
 #ifndef MLK_UI_CHECKBOX_H
 #define MLK_UI_CHECKBOX_H
 
-union mlk_event;
+/**
+ * \file mlk/ui/checkbox.h
+ * \brief GUI checkbox.
+ */
 
 struct mlk_checkbox;
+struct mlk_checkbox_delegate;
+struct mlk_style;
 
-struct mlk_checkbox_style {
-	unsigned long bg_color;
-	unsigned long check_color;
-	unsigned long border_color;
-	unsigned int border_size;
+union mlk_event;
+
+/**
+ * \struct mlk_checkbox
+ * \brief UI clickable checkbox.
+ */
+struct mlk_checkbox {
+	/**
+	 * (read-write)
+	 *
+	 * Position in x.
+	 */
+	int x;
+
+	/**
+	 * (read-write)
+	 *
+	 * Position in y.
+	 */
+	int y;
+
+	/**
+	 * (read-write)
+	 *
+	 * Checkbox width.
+	 */
+	unsigned int w;
+
+	/**
+	 * (read-write)
+	 *
+	 * Checkbox height.
+	 */
+	unsigned int h;
+
+	/**
+	 * (read-write)
+	 *
+	 * Checkbox status, non-zero if activated.
+	 */
+	int checked;
+
+	/**
+	 * (read-write, borrowed)
+	 *
+	 * Checkbox delegate.
+	 */
+	struct mlk_checkbox_delegate *delegate;
+
+	/**
+	 * (read-write, borrowed)
+	 *
+	 * Checkbox style.
+	 */
+	struct mlk_style *style;
 };
 
+/**
+ * \struct mlk_checkbox_delegate
+ * \brief Checkbox delegate.
+ */
 struct mlk_checkbox_delegate {
+	/*
+	 * (read-write, borrowed, optional)
+	 *
+	 * Arbitrary user data.
+	 */
 	void *data;
-	void (*update)(struct mlk_checkbox_delegate *, struct mlk_checkbox *, unsigned int);
-	void (*draw)(struct mlk_checkbox_delegate *, const struct mlk_checkbox *);
+
+	/**
+	 * (read-write, optional)
+	 *
+	 * Handle an event.
+	 *
+	 * \param self this delegate
+	 * \param cb the checkbox
+	 * \param ev the event
+	 * \return the current checkbox status (1 or 0)
+	 */
+	int (*handle)(struct mlk_checkbox_delegate *self,
+	              struct mlk_checkbox *cb,
+	              const union mlk_event *ev);
+
+	/**
+	 * (read-write, optional)
+	 *
+	 * Update the checkbox.
+	 *
+	 * \param self this delegate
+	 * \param cb the checkbox to update
+	 * \param ticks number of ticks since last frame
+	 */
+	void (*update)(struct mlk_checkbox_delegate *self,
+	               struct mlk_checkbox *cb,
+	               unsigned int ticks);
+
+	/**
+	 * (read-write, optional)
+	 *
+	 * Draw this checkbox.
+	 *
+	 * \param self this delegate
+	 * \param cb the checkbox to update
+	 */
+	void (*draw)(struct mlk_checkbox_delegate *self,
+	             const struct mlk_checkbox *cb);
+
+	/**
+	 * (read-write, optional)
+	 *
+	 * Cleanup this delegate associated with the checkbox.
+	 *
+	 * \param self this delegate
+	 * \param cb the underlying checkbox
+	 */
+	void (*finish)(struct mlk_checkbox_delegate *self,
+	               struct mlk_checkbox *cb);
 };
 
-struct mlk_checkbox {
-	int x, y;
-	unsigned int w, h;
-	int checked;
-	struct mlk_checkbox_delegate *delegate;
-	struct mlk_checkbox_style *style;
-};
-
-extern struct mlk_checkbox_style mlk_checkbox_style;
+/**
+ * \brief Default stateless delegate for checkbox.
+ */
 extern struct mlk_checkbox_delegate mlk_checkbox_delegate;
 
 #if defined(__cplusplus)
 extern "C" {
 #endif
 
-int
-mlk_checkbox_ok(const struct mlk_checkbox *cb);
+/**
+ * Initialize the checkbox with default values.
+ *
+ * This is not required if you use designated initializers.
+ *
+ * \pre cb != NULL
+ * \param cb the checkbox to default initialize
+ * \param st style to use (or NULL to use a default)
+ * \param dt delegate to use (or NULL to use a default)
+ */
+void
+mlk_checkbox_init(struct mlk_checkbox *cb,
+                  struct mlk_checkbox_delegate *dt,
+                  struct mlk_style *st);
 
+/**
+ * Invoke ::mlk_checkbox_delegate::update.
+ */
 int
-mlk_checkbox_handle(struct mlk_checkbox *, const union mlk_event *);
+mlk_checkbox_handle(struct mlk_checkbox *cb, const union mlk_event *ev);
 
+/**
+ * Invoke ::mlk_checkbox_delegate::update.
+ */
 void
 mlk_checkbox_update(struct mlk_checkbox *cb, unsigned int ticks);
 
+/**
+ * Invoke ::mlk_checkbox_delegate::draw.
+ */
 void
-mlk_checkbox_draw(const struct mlk_checkbox *);
+mlk_checkbox_draw(const struct mlk_checkbox *cb);
+
+/**
+ * Invoke ::mlk_checkbox_delegate::finish.
+ */
+void
+mlk_checkbox_finish(struct mlk_checkbox *cb);
 
 #if defined(__cplusplus)
 }