Bug at TextArea's lv_ta_get_placeholder_text()

TridentTD · September 19, 2019, 12:53pm

Description

TextArea’s lv_ta_get_placeholder_text() return mistake text.

littlevgl/lvgl/blob/dev-6.1/src/lv_objx/lv_ta.c#L914-L923


const char * lv_ta_get_placeholder_text(lv_obj_t * ta)
{
    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);


    const char * txt = NULL;


    if(ext->placeholder) txt = lv_label_get_text(ext->label);


    return txt;
}

What MCU/Processor/Board and compiler are you using?

ESP32
lvgl6.0.2 master

What do you experience?

What do you expect?

From

const char * lv_ta_get_placeholder_text(lv_obj_t * ta)
{
    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);
    const char * txt = NULL;
    if(ext->placeholder) txt = lv_label_get_text(ext->label);
    return txt;
}

To

const char * lv_ta_get_placeholder_text(lv_obj_t * ta)
{
    lv_ta_ext_t * ext = lv_obj_get_ext_attr(ta);
    const char * txt = NULL;
    if(ext->placeholder) txt = lv_label_get_text(ext->placeholder);
    return txt;
}

Code to reproduce

Screenshot and/or video

embeddedt · September 19, 2019, 12:56pm

Thanks for reporting this; I’ve fixed it in the master branch, and I will merge that branch into dev-6.1 soon so the fix will be there as well.

embeddedt · September 19, 2019, 1:02pm

Merged master into dev-6.1. The bug should be fixed now.

TridentTD · September 19, 2019, 9:33pm

( Another issue: … )

Description

When a textarea’s text is set by utf8 upper than 1 byte
such as the textarea is set by 2 chars like this.

lv_ta_set_text( ta, “柔道” );

and then when changing the textarea to password mode by

lv_ta_set_pwd_mode(ta, true);

The textarea will change the text to a string of * for hiding password-text automatically.
However, on the textarea displays mistake length of the string of *
It is shown by ****** ( 6 chars of * ), not by ** (2 chars of *).

What MCU/Processor/Board and compiler are you using?

ESP32
lvgl 6.0.2 mater

What do you experience?

What do you expect?

After call lv_ta_set_pwd_mode(ta, true);

The text “柔道” should be transformed to ** : 2chars (not ****** : 6 chars).

Code to reproduce

TridentTD · September 19, 2019, 9:44pm

The len at line 655 should come from utf16's strlen() , not from normal strlen() that is utf8’s strlen().

Normal strlen() will return “柔道” to 6 chars.
If transform by utf16's strlen() will return “柔道” to 2 chars.

Maybe should transform by lv_txt_get_encoded_length() ?

github.com

littlevgl/lvgl/blob/master/src/lv_objx/lv_ta.c#L655


if(ext->pwd_mode == 0 && en != false) {
    char * txt   = lv_label_get_text(ext->label);
    uint16_t len = strlen(txt);
    ext->pwd_tmp = lv_mem_alloc(len + 1);
    lv_mem_assert(ext->pwd_tmp);
    if(ext->pwd_tmp == NULL) return;


    strcpy(ext->pwd_tmp, txt);


    uint16_t i;
    for(i = 0; i < len; i++) {
        txt[i] = '*'; /*All char to '*'*/
    }
    txt[i] = '\0';


    lv_ta_clear_selection(ta);


    lv_label_set_text(ext->label, NULL);
}
/*Pwd mode is now disabled*/
else if(ext->pwd_mode == 1 && en == false) {

embeddedt · September 19, 2019, 10:18pm

Can you send a pull request with the change that you think fixes the issue?

TridentTD · September 20, 2019, 3:40am

kisvegabor · September 20, 2019, 6:06am

I’ve merged it to ta_placeholder_copy.
I’ve also fixed the copy of ext->pwd_tmp. Can you test it? IF all work we can merge it to master.

TridentTD · September 20, 2019, 8:50am

The last ta_placeholder_copy,
I tried by the following code for creating by copying password-mode textarea.

  lv_obj_t *password_ta = lv_ta_create(lv_scr_act(), NULL);
    lv_ta_set_pwd_mode(password_ta, true);
    lv_ta_set_text(password_ta, "1234567890");
    lv_ta_set_placeholder_text(password_ta, "Password");
    lv_ta_set_one_line(password_ta, true);
    lv_ta_set_cursor_type(password_ta, LV_CURSOR_NONE);
    lv_obj_set_width(password_ta, 240-12);
    lv_obj_align(password_ta, NULL, LV_ALIGN_CENTER,0,0);

  lv_obj_t *password_ta2 = lv_ta_create(lv_scr_act(), password_ta);
    lv_obj_align(password_ta2, password_ta, LV_ALIGN_OUT_BOTTOM_MID, 0,20);

It occurs runtime-error.

When Checking the runtime-error by ESP Exception Decoder tool.

Error at lv_ta.c line 175.

kisvegabor · September 20, 2019, 9:16am

I’ve fixed it. Now it’s working with your code.

TridentTD · September 20, 2019, 10:15am

The lastest ta_placeholder_copy is OK.
Now it’s working, can copying password-mode textarea to another.

Thank you very mush.

kisvegabor · September 20, 2019, 2:32pm

Great! I’ve merged it to master and dev-6.1.

I copied the fixes manually because the bugfix branch was based on dev-6.1

TridentTD · September 21, 2019, 9:17am

I tried to set a copied textarea to a keyboard,
the keyboard can type well, however when touching for changing cursor position , the texterea is freezed.
Can’t type anymore without any error occurs.

As the following video. ( the copied-textarea is freezed at 0:25 )

Code for 2 textareas.

  lv_obj_t* login_ta = lv_ta_create(lv_scr_act(), NULL);
    lv_obj_set_event_cb(login_ta, ta_event_cb);
    lv_obj_align(login_ta, NULL, LV_ALIGN_CENTER, 0, -40);
    lv_ta_set_one_line(login_ta, true);
    lv_ta_set_cursor_type(login_ta, LV_CURSOR_NONE);
    lv_ta_set_text(login_ta, "");
    lv_ta_set_placeholder_text(login_ta, "Login");

  lv_obj_t* pass_ta = lv_ta_create(lv_scr_act(), NULL);
    lv_obj_set_event_cb(pass_ta, ta_event_cb);
    lv_obj_align(pass_ta, login_ta, LV_ALIGN_OUT_BOTTOM_MID, 0, 20);
    lv_ta_set_pwd_mode(pass_ta,true);
    lv_ta_set_one_line(pass_ta,true);
    lv_ta_set_cursor_type(pass_ta, LV_CURSOR_NONE);
    lv_ta_set_text(pass_ta, "");
    lv_ta_set_placeholder_text(pass_ta, "Password");

Code for event_cb

lv_obj_t* kbd_frame        = NULL;    /* keyboard frame  by lv_obj_create() */
lv_obj_t* kbd_kb           = NULL;    /* keyboard's kb   by lv_kb_create() */
lv_obj_t* kbd_ta           = NULL;    /* keyboard's ta   by copying from outside ta */
lv_obj_t* kbd_ta_outside   = NULL;    /* outside-ta that request to edit */

/* event_cb for kbd_kb . Handle for LV_EVENT_APPLY and LV_EVENT_CANCEL only*/
void kbd_kb_event_cb(lv_obj_t* kbd_kb, lv_event_t ev){
  /* by default kb event_cb first */
  lv_kb_def_event_cb(kbd_kb, ev);

  if(ev == LV_EVENT_APPLY){
    Serial.println("On Apply");
    /* set text to outside-ta from kbd_ta's text */
    if( kbd_ta_outside != NULL) 
      lv_ta_set_text( kbd_ta_outside, lv_ta_get_text( lv_kb_get_ta(kbd_kb) ));

    lv_obj_set_hidden(kbd_frame, true);
    lv_kb_set_ta(kbd_kb, NULL);
    kbd_ta_outside = NULL;
  }else
  if(ev == LV_EVENT_CANCEL){
    Serial.println("On Cancel");
    lv_obj_set_hidden(kbd_frame, true);
    lv_kb_set_ta(kbd_kb, NULL);
    kbd_ta_outside = NULL;
  }
}

/* event_cb for outside-ta. Handle for LV_EVENT_CLICK only*/
void ta_event_cb(lv_obj_t* ta, lv_event_t ev ){
  if(ev != LV_EVENT_CLICKED) return;

  /* create keyboard */  
  if( kbd_frame == NULL) {
    kbd_frame = lv_obj_create(lv_scr_act(), NULL);
      lv_obj_set_size(kbd_frame, 240,240);
    
      kbd_kb = lv_kb_create(kbd_frame, NULL);
        lv_obj_set_size(kbd_kb, 240,180);
        lv_obj_align(kbd_kb, NULL, LV_ALIGN_IN_BOTTOM_MID,0,0);
        lv_obj_set_event_cb(kbd_kb, kbd_kb_event_cb);
  }

  kbd_ta_outside = ta;

  /* delete old kbd_ta */
  if( kbd_ta != NULL) lv_obj_del(kbd_ta); 
  
  /* create kbd_ta by copying from kbd_ta_outside */
  kbd_ta = lv_ta_create(kbd_frame, kbd_ta_outside);
    lv_ta_set_cursor_type(kbd_ta, LV_CURSOR_LINE);
    lv_obj_align(kbd_ta, NULL, LV_ALIGN_IN_TOP_LEFT, 6,6);
    lv_obj_set_width(kbd_ta, 240-12);

  /* set kbd_ta to kbd_kb */
  lv_kb_set_ta(kbd_kb, kbd_ta);

  /* move to forground and unhide */
  lv_obj_move_foreground(kbd_frame);
  lv_obj_set_hidden(kbd_frame, false);
}

kisvegabor · September 21, 2019, 12:55pm

I’ll check it later today.

kisvegabor · September 21, 2019, 3:42pm

I haven’t fully traced issue but it seems the problem is that when you copy the “outside ta” the event callback is also copied. So when you click the copied “inside ta” ta_event_cb is called which messes things up.

This modification in ta_event_cb solved the issue here:

    /* create kbd_ta by copying from kbd_ta_outside */
    kbd_ta = lv_ta_create(kbd_frame, kbd_ta_outside);
    lv_obj_set_event_cb(kbd_ta, NULL);     //Clear the copied event callback

TridentTD · September 22, 2019, 6:40am

Oh, I tried to find the solution many many tests, it doesn’t work.

But by set event_cb to null , it’s work now.
Thank you very much.

kisvegabor · September 22, 2019, 2:52pm

You’re welcome!