156     lv_obj_t * btn = lv_obj_get_child(list, track_id);  in lv_demo_music_list_button_check()  local
157     lv_obj_t * icon = lv_obj_get_child(btn, 0);  in lv_demo_music_list_button_check()
160         lv_obj_add_state(btn, LV_STATE_CHECKED);  in lv_demo_music_list_button_check()
162         lv_obj_scroll_to_view(btn, LV_ANIM_ON);  in lv_demo_music_list_button_check()
165         lv_obj_remove_state(btn, LV_STATE_CHECKED);  in lv_demo_music_list_button_check()
182     lv_obj_t * btn = lv_obj_create(parent);  in add_list_button()  local
183     lv_obj_remove_style_all(btn);  in add_list_button()
185     lv_obj_set_size(btn, lv_pct(100), 110);  in add_list_button()
187     lv_obj_set_size(btn, lv_pct(100), 60);  in add_list_button()
190     lv_obj_add_style(btn, &style_btn, 0);  in add_list_button()
191     lv_obj_add_style(btn, &style_button_pr, LV_STATE_PRESSED);  in add_list_button()
192     lv_obj_add_style(btn, &style_button_chk, LV_STATE_CHECKED);  in add_list_button()
193     lv_obj_add_style(btn, &style_button_dis, LV_STATE_DISABLED);  in add_list_button()
194     lv_obj_add_event_cb(btn, btn_click_event_cb, LV_EVENT_CLICKED, NULL);  in add_list_button()
197         lv_obj_add_state(btn, LV_STATE_DISABLED);  in add_list_button()
200     lv_obj_t * icon = lv_image_create(btn);  in add_list_button()
204     lv_obj_t * title_label = lv_label_create(btn);  in add_list_button()
209     lv_obj_t * artist_label = lv_label_create(btn);  in add_list_button()
214     lv_obj_t * time_label = lv_label_create(btn);  in add_list_button()
220     lv_obj_t * border = lv_image_create(btn);  in add_list_button()
227     return btn;  in add_list_button()
232     lv_obj_t * btn = lv_event_get_target(e);  in btn_click_event_cb()  local
234     uint32_t idx = lv_obj_get_index(btn);  in btn_click_event_cb()