Events

lv_display_add_event_cb(disp, event_cb, LV_EVENT_..., user_data) adds an event handler to a display.

If you added user_data to the Display, you can retrieve it in an event like this:

lv_display_t * display1;
my_type_t    * my_user_data;
display1 = (lv_display_t *)lv_event_get_current_target(e);
my_user_data = lv_display_get_user_data(display1);

The following events are sent for Display (lv_display_t) objects:

• LV_EVENT_INVALIDATE_AREA An area is invalidated (marked for redraw). lv_event_get_param(e) returns a pointer to an lv_area_t object with the coordinates of the area to be invalidated. The area can be freely modified if needed to adapt it a special requirement of the display. Usually needed with monochrome displays to invalidate N x 8 rows or columns in one pass.

• LV_EVENT_RESOLUTION_CHANGED: Sent when the resolution changes due to lv_display_set_resolution() or lv_display_set_rotation().

• LV_EVENT_COLOR_FORMAT_CHANGED: Sent as a result of any call to lv_display_set_color_format().

• LV_EVENT_REFR_REQUEST: Sent when something happened that requires redraw.

• LV_EVENT_REFR_START: Sent before a refreshing cycle starts. Sent even if there is nothing to redraw.

• LV_EVENT_REFR_READY: Sent when refreshing has been completed (after rendering and calling Flush Callback). Sent even if no redraw happened.

• LV_EVENT_RENDER_START: Sent just before rendering begins.

• LV_EVENT_RENDER_READY: Sent after rendering has been completed (before calling Flush Callback)

• LV_EVENT_FLUSH_START: Sent before Flush Callback is called.

• LV_EVENT_FLUSH_FINISH: Sent after Flush Callback call has returned.

• LV_EVENT_FLUSH_WAIT_START: Sent at the beginning of internal call to wait_for_flushing() – happens whether or not any waiting will actually occur. Call returns immediately if disp->flushing == 0.

• LV_EVENT_FLUSH_WAIT_FINISH: Sent when the call to wait_for_flushing() is about to return, regardless whether any actual waiting occurred.