Choices: clearChoice remove placeholder too

[kl3sk]

Describe the bug
Clearing the choices will remove all ! Placeholder too.

To Reproduce
Steps to reproduce the behavior:

1. Create a Choice from an select with a placeholder (option with value="")
2. programmatically Choice.clearChoices()
3. All is removed

Expected behavior
Have a choice to keep or not the placeholder

[ch3rn1k]

Any way you can clear it with .setChoiceByValue('') without losing placeholder

[kl3sk]

@ch3rn1k You mean, .setChoiceByValue(‘’) before .clearChoices() ?

[kl3sk]

I'll try what you said, in fact it works, but I understand I have miss something to explain.
I use .setChoices(data,'id', 'fullName', true) and this is this method who clear all, due to the 4th argument.

At leat I my trick is this for the moment:

const placeholder = Choice.setChoiceByValue('').getValue()
// retrieve data from Ajax

Choice.clearChoices().setChoices(ajaxData, 'id', 'fullName', true).setChoices([placeholder]).setChoiceByValue('')

[alfonsoar]

Any way you can clear it with .setChoiceByValue('') without losing placeholder

although this works what would happen of a choice has a value of ''

[kl3sk]

@agar23 this will be useless because not really usable on a real form.

[alfonsoar]

@kl3sk fair enough, I was thinking from more of a lib perspective. As a developer I expect the clearChoices() method to work correctly out the box and not clear my placeholder.

I should not have to use .setChoiceByValue('') as a "workaround" to properly clear my choices.

You make a fair point, its probably not very practical to have an option with a value of "" on a real world form.

[kl3sk]

In a symfony world, placeholder are set with a blank '' value.
@jshjohnson said on the doc, the recommended way of adding a placeholder is as follows. And I totally agree with it.

As a lib perspective, everything could be considered as anything.

So it is still available, but .clearChoices should clear choices an empty value is not a choice.

[alfonsoar]

but a choice can have an empty value ("") as a value.....

[kl3sk]

Yes this is possible, but unless reading the textValue it reamins useless ^^.

Anyway, without any jokes a choice should be done for the placeholder 😉

[bupy7]

Hard fix:

selectElement.addEventListener('removeItem', function () {
    if (selectElement.length === 0) {
        choicesInstance
            .setChoices([{value: '', label: 'None', placeholder: true}], 'value', 'label', true)
            .setChoiceByValue('');
    }
});

[kl3sk]

@bupy7 this doesn’t keep the original placeholder.

[bupy7]

@kl3sk if you add placeholder programmatically (I recommend that) is no matter.

[kl3sk]

That’s I did in a previous comment.

[bupy7]

@kl3sk, not the same.

Your solution has many side effects:

1. setChoiceByValue('')
2. clearChoices()
3. setChoices()
4. setChoices() again
5. setChoiceByValue() again

My solution solve the problem in two step:

1. setChoices()
2. setChoiceByValue()

[kl3sk]

I want to keep the original placeholder, generated by (in my case) Symfony formbuilder.
In order to keep it, I have to select it save it and reinject it.

[yogeshjain999]

This workaround worked for me (when getting data using ajax). It preserved the placeholder, without needing to do setChoiceByValue('')

if (select.value) choices.clearStore();

choices.setChoices(async () => {
  const data = await fetch('/states');
  return data.json();
});

[FelixWienberg]

I combined some of the previous mentioned workarounds, but rather used Array.prototype.find on the config-Object rather than setChoiceByValue('').getValue() for storing the original placeholder, and came up with this here:

newOptions.push(choicesInstance.config.choices.find(choice => choice.placeholder));
choicesInstance.setChoices(newOptions, 'value', 'label', true) 
   .setChoiceByValue('');

[kl3sk]

Very intersting way @FelixWienberg , I use your solution instead of mine.

At least @jshjohnson should implement something for this.