Commits
-------
57cc531 [Form] Improved PHPDocs of choice lists
9e7e2af [Form] Fixed PHPDoc: Used {@inheritdoc} where applicable
2c530cc Fixed typos in UPGRADE file
7899bea Added examples to UPGRADE
d346ae6 Improved choice list sections of UPGRADE and CHANGELOG
a676598 [Form] Added class LazyChoiceList
Discussion
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[Form] Added LazyChoiceList
Bug fix: no
Feature addition: yes
Backwards compatibility break: no
Symfony2 tests pass: yes
Fixes the following tickets: -
Todo: -
Adds a ChoiceList implementation that satisfies people who formerly extended ArrayChoiceList and loaded choices lazily in its `load` method.
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by craue at 2012-01-30T12:56:49Z
👍
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by craue at 2012-01-30T14:55:38Z
Not sure if it's a bug in this PR or in #3156, but the labels get replaced by their keys:
```php
<?php
use Symfony\Component\Form\Extension\Core\ChoiceList\ChoiceList;
use Symfony\Component\Form\Extension\Core\ChoiceList\LazyChoiceList;
use Symfony\Component\Form\Extension\Core\ChoiceList\SimpleChoiceList;
class MyChoiceList extends LazyChoiceList {
protected function loadChoiceList() {
$choices = array(
'bla' => 'blaaaaaahhhh',
);
return new SimpleChoiceList($choices, array(), ChoiceList::COPY_CHOICE, ChoiceList::COPY_CHOICE);
}
public function getChoices() {
$choices = parent::getChoices();
// $choices is array('bla' => 'bla')
return $choices;
}
}
```
If it's not this PR, I can of course open a new ticket for that. But I'm only working with `LazyChoiceList`s.
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by stof at 2012-01-30T16:07:41Z
@craue the ``SimpleChoiceList`` is an implementation using the same string as label and value. If you need different ones, you need to use the ``ChoiceList`` implementation.
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by craue at 2012-01-30T16:22:06Z
@stof: That would make `SimpleChoiceList` useless for almost any case. Are you sure?
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by craue at 2012-01-30T16:33:31Z
The bug even occurs when using
```
return new ChoiceList(array_keys($choices), array_values($choices), array(), ChoiceList::COPY_CHOICE, ChoiceList::COPY_CHOICE);
```
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by stof at 2012-01-30T16:40:19Z
well, the SimpleChoiceList is for simple cases (thus its naming) where you want the same for the label and the values. And if you look at the class, you will see it extends the ChoiceList implementation which is the generic one.
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by craue at 2012-01-30T16:53:36Z
For me, "simple" would mean that it just takes the array given, using keys as indices and values as labels. No fancy stuff messing around with anything. :D But, is there anything wrong in this code or in mine? @bschussek: Please enlighten me.
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by bschussek at 2012-01-30T17:16:58Z
You are both wrong :) `getChoices` does not return the choices with their associated labels anymore. What you get now are the choice indices as array keys and the choice values as array values. How both are determined depends on the index and value generation strategy, which, in your case, are both COPY_CHOICE.
The difference between simple and complex choice lists is, that simple choice lists can only contain scalar values as choices, while other choice lists (such as ObjectChoiceList, EntityChoiceList) may contain objects as choices.
Choice labels are now stored in ChoiceView objects, which are returned by the various `get*Views` methods.
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by craue at 2012-01-30T18:07:43Z
It's pretty annoying having provided an array with keys and values when initializing the `ChoiceList` but being unable to retrieve it again. Guess I just over-used or even abused those choice lists as kind of (not only form related) lookup tables.
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by bschussek at 2012-01-30T19:27:21Z
@craue: What's your use case?
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by craue at 2012-01-30T20:10:16Z
I just used choice lists extensively, even for not directly form-related stuff. In one case, I'm using two of them (which are also used individually) to build up a third one. That went well using the old `ArrayChoiceList`s and their `getChoices` method. Just thinking about creating another set of model classes which just contain my lists. So for only one select field in a form it'll take three classes then: (A) a list, (B) a choice list based on A, (C) a choice form type based on B. Oh well ... :D
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by craue at 2012-01-30T21:31:32Z
Anyway, this PR for `LazyChoiceList` is great, so please merge it. ;)
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by craue at 2012-01-31T14:00:46Z
@bschussek: Is it ready to be merged?
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by bschussek at 2012-01-31T16:59:17Z
Yes
4682b096f6
