From 962837938221dd1b026755219da943609ffd059a Mon Sep 17 00:00:00 2001 From: Joey Castillo Date: Tue, 21 Dec 2021 12:58:05 -0600 Subject: add comments to 'hello there' face --- movement/movement_config.h | 1 - movement/watch_faces/demos/hello_there_face.c | 34 ++++++++++++++++++++++++++- 2 files changed, 33 insertions(+), 2 deletions(-) diff --git a/movement/movement_config.h b/movement/movement_config.h index 047628ad..afb2902c 100644 --- a/movement/movement_config.h +++ b/movement/movement_config.h @@ -20,7 +20,6 @@ const watch_face_t watch_faces[] = { simple_clock_face, - hello_there_face, preferences_face, set_time_face, }; diff --git a/movement/watch_faces/demos/hello_there_face.c b/movement/watch_faces/demos/hello_there_face.c index e023b9d3..ad535533 100644 --- a/movement/watch_faces/demos/hello_there_face.c +++ b/movement/watch_faces/demos/hello_there_face.c @@ -4,18 +4,25 @@ #include "watch.h" void hello_there_face_setup(movement_settings_t *settings, uint8_t watch_face_index, void ** context_ptr) { + // These next two lines just silence the compiler warnings associated with unused parameters. + // We have no use for the settings or the watch_face_index, so we make that explicit here. (void) settings; (void) watch_face_index; + // At boot, context_ptr will be NULL indicating that we don't have anyplace to store our context. if (*context_ptr == NULL) { + // in this case, we allocate an area of memory sufficient to store the stuff we need to track. *context_ptr = malloc(sizeof(hello_there_state_t)); - memset(*context_ptr, 0, sizeof(hello_there_state_t)); } } void hello_there_face_activate(movement_settings_t *settings, void *context) { + // same as above: silence the warning, we don't need to check the settings. (void) settings; + // we do however need to set some things in our context. Here we cast it to the correct type... hello_there_state_t *state = (hello_there_state_t *)context; + // ...and set the initial state of our watch face. We start out displaying the word 'Hello', state->current_word = 0; + // and animate by default. state->animating = true; } @@ -26,22 +33,45 @@ bool hello_there_face_loop(movement_event_t event, movement_settings_t *settings switch (event.event_type) { case EVENT_ACTIVATE: case EVENT_TICK: + // on activate and tick, if we are animating, if (state->animating) { + // we display the current word, if (state->current_word == 0) watch_display_string("Hello ", 4); else watch_display_string(" there", 4); + // and increment it so that it will update on the next tick. state->current_word = (state->current_word + 1) % 2; } break; case EVENT_MODE_BUTTON_UP: + // when the user presses 'mode', we tell movement to move to the next watch face. + // movement will call our resign function, clear the screen, and transfer control + // to the next watch face in the list. movement_move_to_next_face(); break; case EVENT_LIGHT_BUTTON_UP: + // when the user presses 'light', we illuminate the LED. We could override this if + // our UI needed an additional button for input, consuming the light button press + // but not illuminating the LED. movement_illuminate_led(); break; case EVENT_ALARM_BUTTON_UP: + // when the user presses 'alarm', we toggle the state of the animation. If animating, + // we stop; if stopped, we resume. state->animating = !state->animating; break; + case EVENT_LOW_ENERGY_UPDATE: + // This low energy mode update occurs once a minute, if the watch face is in the + // foreground when Movement enters low energy mode. We have the option of supporting + // this mode, but since our watch face animates once a second, the "Hello there" face + // isn't very useful in this mode. So we choose not to support it. (continued below) + break; case EVENT_TIMEOUT: + // ... Instead, we respond to the timeout event. This event happens after a configurable + // interval on screen (1-30 minutes). The watch will give us this event as a chance to + // resign control if we want to, and in this case, we do. + // This function will return the watch to the first screen (usually a simple clock), + // and it will do it long before the watch enters low energy mode. This ensures we + // won't be on screen, and thus opts us out of getting the EVENT_LOW_ENERGY_UPDATE above. movement_move_to_face(0); default: break; @@ -51,6 +81,8 @@ bool hello_there_face_loop(movement_event_t event, movement_settings_t *settings } void hello_there_face_resign(movement_settings_t *settings, void *context) { + // our watch face, like most watch faces, has nothing special to do when resigning. + // watch faces that enable a peripheral or interact with a sensor may want to turn it off here. (void) settings; (void) context; } -- cgit v1.2.3