List (lv_list)¶
Overview¶
The List is basically a rectangle with vertical layout to which Buttons and Texts can be added
Parts and Styles¶
Background
LV_PART_MAIN
The main part of the list that uses all the typical background propertiesLV_PART_SCROLLBAR
The scrollbar. See the Base objects documentation for details.
Buttons and Texts See the Button's and Label's documentation.
Usage¶
Buttons¶
lv_list_add_btn(list, icon, text)
adds a full-width button with an icon - that can be an image or symbol - and a text.
The text starts to scroll horizontally if it's too long.
Texts¶
lv_list_add_text(list, text)
adds a text.
Events¶
No special events are sent by the List, but sent by the Button as usual.
Learn more about Events.
Example¶
Simple List¶
C code
GitHub#include "../../lv_examples.h"
#if LV_USE_LIST && LV_BUILD_EXAMPLES
static lv_obj_t * list1;
static void event_handler(lv_event_t * e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t * obj = lv_event_get_target(e);
if(code == LV_EVENT_CLICKED) {
LV_LOG_USER("Clicked: %s", lv_list_get_btn_text(list1, obj));
}
}
void lv_example_list_1(void)
{
/*Create a list*/
list1 = lv_list_create(lv_scr_act());
lv_obj_set_size(list1, 180, 220);
lv_obj_center(list1);
/*Add buttons to the list*/
lv_obj_t * btn;
lv_list_add_text(list1, "File");
btn = lv_list_add_btn(list1, LV_SYMBOL_FILE, "New");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_DIRECTORY, "Open");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_SAVE, "Save");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_CLOSE, "Delete");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_EDIT, "Edit");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_list_add_text(list1, "Connectivity");
btn = lv_list_add_btn(list1, LV_SYMBOL_BLUETOOTH, "Bluetooth");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_GPS, "Navigation");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_USB, "USB");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_BATTERY_FULL, "Battery");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_list_add_text(list1, "Exit");
btn = lv_list_add_btn(list1, LV_SYMBOL_OK, "Apply");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
btn = lv_list_add_btn(list1, LV_SYMBOL_CLOSE, "Close");
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
}
#endif
def event_handler(e):
code = e.get_code()
obj = e.get_target()
if code == lv.EVENT.CLICKED:
print("Clicked: list1." + list1.get_btn_text(obj))
# Create a list
list1 = lv.list(lv.scr_act())
list1.set_size(180, 220)
list1.center()
# Add buttons to the list
list1.add_text("File")
btn_new = list1.add_btn(lv.SYMBOL.FILE, "New")
btn_new.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_open = list1.add_btn(lv.SYMBOL.DIRECTORY, "Open")
btn_open.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_save = list1.add_btn(lv.SYMBOL.SAVE, "Save")
btn_save.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_delete = list1.add_btn(lv.SYMBOL.CLOSE, "Delete")
btn_delete.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_edit = list1.add_btn(lv.SYMBOL.EDIT, "Edit")
btn_edit.add_event_cb(event_handler,lv.EVENT.ALL, None)
list1.add_text("Connectivity")
btn_bluetooth = list1.add_btn(lv.SYMBOL.BLUETOOTH, "Bluetooth")
btn_bluetooth.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_navig = list1.add_btn(lv.SYMBOL.GPS, "Navigation")
btn_navig.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_USB = list1.add_btn(lv.SYMBOL.USB, "USB")
btn_USB.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_battery = list1.add_btn(lv.SYMBOL.BATTERY_FULL, "Battery")
btn_battery.add_event_cb(event_handler,lv.EVENT.ALL, None)
list1.add_text("Exit")
btn_apply = list1.add_btn(lv.SYMBOL.OK, "Apply")
btn_apply.add_event_cb(event_handler,lv.EVENT.ALL, None)
btn_close = list1.add_btn(lv.SYMBOL.CLOSE, "Close")
btn_close.add_event_cb(event_handler,lv.EVENT.ALL, None)
Sorting a List using up and down buttons¶
C code
GitHub#include <stdlib.h>
#include "../../lv_examples.h"
#if LV_USE_LIST && LV_BUILD_EXAMPLES
static lv_obj_t* list1;
static lv_obj_t* list2;
static lv_obj_t* currentButton = NULL;
static void event_handler(lv_event_t* e)
{
lv_event_code_t code = lv_event_get_code(e);
lv_obj_t* obj = lv_event_get_target(e);
if (code == LV_EVENT_CLICKED)
{
LV_LOG_USER("Clicked: %s", lv_list_get_btn_text(list1, obj));
if (currentButton == obj)
{
currentButton = NULL;
}
else
{
currentButton = obj;
}
lv_obj_t* parent = lv_obj_get_parent(obj);
uint32_t i;
for (i = 0; i < lv_obj_get_child_cnt(parent); i++)
{
lv_obj_t* child = lv_obj_get_child(parent, i);
if (child == currentButton)
{
lv_obj_add_state(child, LV_STATE_CHECKED);
}
else
{
lv_obj_clear_state(child, LV_STATE_CHECKED);
}
}
}
}
static void event_handler_top(lv_event_t* e)
{
lv_event_code_t code = lv_event_get_code(e);
if (code == LV_EVENT_CLICKED)
{
if (currentButton == NULL) return;
lv_obj_move_background(currentButton);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_up(lv_event_t* e)
{
lv_event_code_t code = lv_event_get_code(e);
if ((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT))
{
if (currentButton == NULL) return;
uint32_t index = lv_obj_get_index(currentButton);
if (index <= 0) return;
lv_obj_move_to_index(currentButton, index - 1);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_center(lv_event_t* e)
{
const lv_event_code_t code = lv_event_get_code(e);
if ((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT))
{
if (currentButton == NULL) return;
lv_obj_t* parent = lv_obj_get_parent(currentButton);
const uint32_t pos = lv_obj_get_child_cnt(parent) / 2;
lv_obj_move_to_index(currentButton, pos);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_dn(lv_event_t* e)
{
const lv_event_code_t code = lv_event_get_code(e);
if ((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT))
{
if (currentButton == NULL) return;
const uint32_t index = lv_obj_get_index(currentButton);
lv_obj_move_to_index(currentButton, index + 1);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_bottom(lv_event_t* e)
{
const lv_event_code_t code = lv_event_get_code(e);
if (code == LV_EVENT_CLICKED)
{
if (currentButton == NULL) return;
lv_obj_move_foreground(currentButton);
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
static void event_handler_swap(lv_event_t* e)
{
const lv_event_code_t code = lv_event_get_code(e);
// lv_obj_t* obj = lv_event_get_target(e);
if ((code == LV_EVENT_CLICKED) || (code == LV_EVENT_LONG_PRESSED_REPEAT))
{
uint32_t cnt = lv_obj_get_child_cnt(list1);
for (int i = 0; i < 100; i++)
if (cnt > 1)
{
lv_obj_t* obj = lv_obj_get_child(list1, rand() % cnt);
lv_obj_move_to_index(obj, rand() % cnt);
if (currentButton != NULL)
{
lv_obj_scroll_to_view(currentButton, LV_ANIM_ON);
}
}
}
}
void lv_example_list_2(void)
{
/*Create a list*/
list1 = lv_list_create(lv_scr_act());
lv_obj_set_size(list1, lv_pct(60), lv_pct(100));
lv_obj_set_style_pad_row(list1, 5, 0);
/*Add buttons to the list*/
lv_obj_t* btn;
int i;
for (i = 0; i < 15; i++) {
btn = lv_btn_create(list1);
lv_obj_set_width(btn, lv_pct(50));
lv_obj_add_event_cb(btn, event_handler, LV_EVENT_CLICKED, NULL);
lv_obj_t* lab = lv_label_create(btn);
lv_label_set_text_fmt(lab, "Item %d", i);
}
/*Select the first button by default*/
currentButton = lv_obj_get_child(list1, 0);
lv_obj_add_state(currentButton, LV_STATE_CHECKED);
/*Create a second list with up and down buttons*/
list2 = lv_list_create(lv_scr_act());
lv_obj_set_size(list2, lv_pct(40), lv_pct(100));
lv_obj_align(list2, LV_ALIGN_TOP_RIGHT, 0, 0);
lv_obj_set_flex_flow(list2, LV_FLEX_FLOW_COLUMN);
btn = lv_list_add_btn(list2, NULL, "Top");
lv_obj_add_event_cb(btn, event_handler_top, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_UP, "Up");
lv_obj_add_event_cb(btn, event_handler_up, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_LEFT, "Center");
lv_obj_add_event_cb(btn, event_handler_center, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_DOWN, "Down");
lv_obj_add_event_cb(btn, event_handler_dn, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, NULL, "Bottom");
lv_obj_add_event_cb(btn, event_handler_bottom, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
btn = lv_list_add_btn(list2, LV_SYMBOL_SHUFFLE, "Shuffle");
lv_obj_add_event_cb(btn, event_handler_swap, LV_EVENT_ALL, NULL);
lv_group_remove_obj(btn);
}
#endif
import urandom
currentButton = None
list1 = None
def event_handler(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED:
if currentButton == obj:
currentButton = None
else:
currentButton = obj
parent = obj.get_parent()
for i in range( parent.get_child_cnt()):
child = parent.get_child(i)
if child == currentButton:
child.add_state(lv.STATE.CHECKED)
else:
child.clear_state(lv.STATE.CHECKED)
def event_handler_top(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED:
if currentButton == None:
return
currentButton.move_background()
currentButton.scroll_to_view( lv.ANIM.ON)
def event_handler_up(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
index = currentButton.get_index()
if index <= 0:
return
currentButton.move_to_index(index - 1)
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_center(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
parent = currentButton.get_parent()
pos = parent.get_child_cnt() // 2
currentButton.move_to_index(pos)
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_dn(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
index = currentButton.get_index()
currentButton.move_to_index(index + 1)
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_bottom(evt):
global currentButton
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED or code == lv.EVENT.LONG_PRESSED_REPEAT:
if currentButton == None:
return
currentButton.move_foreground()
currentButton.scroll_to_view(lv.ANIM.ON)
def event_handler_swap(evt):
global currentButton
global list1
code = evt.get_code()
obj = evt.get_target()
if code == lv.EVENT.CLICKED:
cnt = list1.get_child_cnt()
for i in range(100):
if cnt > 1:
obj = list1.get_child(urandom.getrandbits(32) % cnt )
obj.move_to_index(urandom.getrandbits(32) % cnt)
if currentButton != None:
currentButton.scroll_to_view(lv.ANIM.ON)
#Create a list with buttons that can be sorted
list1 = lv.list(lv.scr_act())
list1.set_size(lv.pct(60), lv.pct(100))
list1.set_style_pad_row( 5, 0)
for i in range(15):
btn = lv.btn(list1)
btn.set_width(lv.pct(100))
btn.add_event_cb( event_handler, lv.EVENT.CLICKED, None)
lab = lv.label(btn)
lab.set_text("Item " + str(i))
#Select the first button by default
currentButton = list1.get_child(0)
currentButton.add_state(lv.STATE.CHECKED)
#Create a second list with up and down buttons
list2 = lv.list(lv.scr_act())
list2.set_size(lv.pct(40), lv.pct(100))
list2.align(lv.ALIGN.TOP_RIGHT, 0, 0)
list2.set_flex_flow(lv.FLEX_FLOW.COLUMN)
btn = list2.add_btn(None, "Top")
btn.add_event_cb(event_handler_top, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.UP, "Up")
btn.add_event_cb(event_handler_up, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.LEFT, "Center")
btn.add_event_cb(event_handler_center, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.DOWN, "Down")
btn.add_event_cb(event_handler_dn, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(None, "Bottom")
btn.add_event_cb(event_handler_bottom, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
btn = list2.add_btn(lv.SYMBOL.SHUFFLE, "Shuffle")
btn.add_event_cb(event_handler_swap, lv.EVENT.ALL, None)
lv.group_remove_obj(btn)
API¶
Functions