Lines Matching +full:- +full:c
19 Enable Widget ID functionality by setting :c:macro:`LV_USE_OBJ_ID` to ``1`` in ``lv_conf.h``.
23 - each Widget will now have a ``void *`` field called ``id``;
24 - these two API functions become available:
26 - :cpp:expr:`lv_obj_get_id(widget)`,
27 - :cpp:expr:`lv_obj_get_child_by_id(widget, id)`;
29 - several more Widget-ID-related API functions become available if
30 :c:macro:`LV_USE_OBJ_ID_BUILTIN` is non-zero (more on this below);
31 - two additional configuration macros both :c:macro:`LV_OBJ_ID_AUTO_ASSIGN` and
32 :c:macro:`LV_USE_OBJ_ID_BUILTIN` now have meaning.
35 :c:macro:`LV_OBJ_ID_AUTO_ASSIGN`
36 --------------------------------
38 This macro in ``lv_conf.h`` defaults to whatever value :c:macro:`LV_USE_OBJ_ID`
40 non-zero value, it causes two things to happen:
42 - :cpp:expr:`lv_obj_assign_id(class_p, widget)` will be called at the end of each
44 - :cpp:expr:`lv_obj_free_id(widget)` will be called at the end of the sequence when
54 This function (whether provided by LVGL or by you --- more on this below) is
61 This function (whether provided by LVGL or by you --- more on this below) is
62 responsible for doing the clean-up of any resources allocated by
66 :c:macro:`LV_USE_OBJ_ID_BUILTIN`
67 --------------------------------
70 wish. When it equates to a non-zero value the following function implementations are
73 - :cpp:expr:`lv_obj_assign_id(class_p, widget)`
74 - :cpp:expr:`lv_obj_free_id(widget)`
75 - :cpp:expr:`lv_obj_set_id(widget, id)`
76 - :cpp:expr:`lv_obj_stringify_id(widget, buf, len)`
77 - :cpp:expr:`lv_obj_id_compare(id1, id2)`
83 - Screen
84 - Label
85 - Button
86 - Label
87 - Label
88 - Image
92 - obj1
93 - label1
94 - btn1
95 - label2
96 - label3
97 - image1
105 ---------------------------
107 If you wish, you can provide custom implementations for several Widget-ID related
108 functions. You do this by first setting :c:macro:`LV_USE_OBJ_ID_BUILTIN` to `0` in
114 .. code-block:: c
119 If :c:macro:`LV_OBJ_ID_AUTO_ASSIGN` equates to a non-zero value (or if you otherwise
122 .. code-block:: c
127 If :c:macro:`LV_BUILD_TEST` equates to a non-zero value and you are including LVGL
131 .. code-block:: c
136 Examples of implementations of these functions exist in ``lv_obj_id_builtin.c``, but
144 they are considered equal, and non-zero otherwise.
146 If :c:macro:`LV_OBJ_ID_AUTO_ASSIGN` equates to a non-zero value,
151 Widget IDs. Note that this pointer may be different than :cpp:expr:`widget->class_p`
154 If :c:macro:`LV_OBJ_ID_AUTO_ASSIGN` equates to a non-zero value,
156 the clean-up for any resources allocated by :cpp:func:`lv_obj_assign_id`.
160 ---------------------
165 currently-configured method used by the :c:macro:`LV_LOG_USER` macro. If NULL is
169 For :c:macro:`LV_LOG_USER` to produce output, the following needs to be true in
172 - :c:macro:`LV_USE_LOG` must equate to a non-zero value
173 - :c:macro:`LV_LOG_LEVEL` <= :c:macro:`LV_LOG_LEVEL_USER`
177 :c:macro:`LV_USE_OBJ_ID` equates to a non-zero value, will also print the output of
184 :cpp:expr:`timer->user_data` field when the timer event callback is called, attempted
191 ----------------