<p dir="auto">I've updated to <strong>2.7</strong> and changed my choice types to use <code class="notranslate">choices_as_values</code>.<br>
Most of my choices are simple "No" or "Yes". But they must not be preselected - the user is forced to choose. That is why none of my radio buttons is initially checked.</p>
<p dir="auto">I tried this with <strong>2.7</strong>:</p>
<div class="highlight highlight-text-html-php notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="$builder-&gt;add('aberdeenBlind', 'choice', array(
                'choices' =&gt; array(
                    'Ja' =&gt; true,
                    'Nein' =&gt; false
                ),
                'choices_as_values' =&gt; true,
                'expanded' =&gt; true,
                'required' =&gt; true
            ))"><pre class="notranslate"><span class="pl-s1"><span class="pl-c1">$</span>builder</span>-&gt;<span class="pl-en">add</span>(<span class="pl-s">'aberdeenBlind'</span>, <span class="pl-s">'choice'</span>, <span class="pl-en">array</span>(
                <span class="pl-s">'choices'</span> =&gt; <span class="pl-en">array</span>(
                    <span class="pl-s">'Ja'</span> =&gt; <span class="pl-c1">true</span>,
                    <span class="pl-s">'Nein'</span> =&gt; <span class="pl-c1">false</span>
                ),
                <span class="pl-s">'choices_as_values'</span> =&gt; <span class="pl-c1">true</span>,
                <span class="pl-s">'expanded'</span> =&gt; <span class="pl-c1">true</span>,
                <span class="pl-s">'required'</span> =&gt; <span class="pl-c1">true</span>
            ))</pre></div>
<p dir="auto">Unfortunately the second radio button (false =&gt; 'Nein') is preselected. This also happens when flipping the order of the <code class="notranslate">choices</code>. The <code class="notranslate">false</code> choice is always preselected.</p>
<p dir="auto">I played around with other options e.g. <code class="notranslate">placeholder</code>, <code class="notranslate">empty_*</code> etc. but then I recognized:<br>
<strong>This only seems to happen when using <code class="notranslate">boolean</code> values. The following example would not preselect any value</strong>:</p>
<div class="highlight highlight-text-html-php notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="$builder-&gt;add('aberdeenBlind', 'choice', array(
                'choices' =&gt; array(
                    'Ja' =&gt; 'Y', // or '1'
                    'Nein' =&gt; 'N' // or '0'
                ),
                'choices_as_values' =&gt; true,
                'expanded' =&gt; true,
                'required' =&gt; true
            ))"><pre class="notranslate"><span class="pl-s1"><span class="pl-c1">$</span>builder</span>-&gt;<span class="pl-en">add</span>(<span class="pl-s">'aberdeenBlind'</span>, <span class="pl-s">'choice'</span>, <span class="pl-en">array</span>(
                <span class="pl-s">'choices'</span> =&gt; <span class="pl-en">array</span>(
                    <span class="pl-s">'Ja'</span> =&gt; <span class="pl-s">'Y'</span>, <span class="pl-c">// or '1'</span>
                    <span class="pl-s">'Nein'</span> =&gt; <span class="pl-s">'N'</span> <span class="pl-c">// or '0'</span>
                ),
                <span class="pl-s">'choices_as_values'</span> =&gt; <span class="pl-c1">true</span>,
                <span class="pl-s">'expanded'</span> =&gt; <span class="pl-c1">true</span>,
                <span class="pl-s">'required'</span> =&gt; <span class="pl-c1">true</span>
            ))</pre></div>
<p dir="auto">Possibly related:</p>
<ul dir="auto">
<li><a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="78862929" data-permission-text="Title is private" data-url="https://github.com/symfony/symfony/issues/14712" data-hovercard-type="issue" data-hovercard-url="/symfony/symfony/issues/14712/hovercard" href="https://github.com/symfony/symfony/issues/14712">#14712</a> by <a class="user-mention notranslate" data-hovercard-type="user" data-hovercard-url="/users/maxailloud/hovercard" data-octo-click="hovercard-link-click" data-octo-dimensions="link_type:self" href="https://github.com/maxailloud">@maxailloud</a></li>
<li><a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="101526807" data-permission-text="Title is private" data-url="https://github.com/symfony/symfony/issues/15573" data-hovercard-type="issue" data-hovercard-url="/symfony/symfony/issues/15573/hovercard" href="https://github.com/symfony/symfony/issues/15573">#15573</a> by <a class="user-mention notranslate" data-hovercard-type="user" data-hovercard-url="/users/imphil/hovercard" data-octo-click="hovercard-link-click" data-octo-dimensions="link_type:self" href="https://github.com/imphil">@imphil</a></li>
</ul>
<p dir="auto">Using Symfony 2.8.2 or 3.0.2.<br>
You can reproduce the problem with this simple statement:</p>
<div class="highlight highlight-text-html-php notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="$builder-&gt;add('participation', ChoiceType::class, array(
     'choices' =&gt; [ 'yes' =&gt; true, 'no' =&gt; false ],
    'placeholder' =&gt; 'Select a value',
    'empty_data' =&gt; null,
    'choices_as_values' =&gt; true,
));"><pre class="notranslate"><span class="pl-s1"><span class="pl-c1">$</span>builder</span>-&gt;<span class="pl-en">add</span>(<span class="pl-s">'participation'</span>, <span class="pl-v">ChoiceType</span>::class, <span class="pl-en">array</span>(
     <span class="pl-s">'choices'</span> =&gt; [ <span class="pl-s">'yes'</span> =&gt; <span class="pl-c1">true</span>, <span class="pl-s">'no'</span> =&gt; <span class="pl-c1">false</span> ],
    <span class="pl-s">'placeholder'</span> =&gt; <span class="pl-s">'Select a value'</span>,
    <span class="pl-s">'empty_data'</span> =&gt; <span class="pl-c1">null</span>,
    <span class="pl-s">'choices_as_values'</span> =&gt; <span class="pl-c1">true</span>,
));</pre></div>
<p dir="auto">Expected result:</p>
<div class="highlight highlight-text-html-basic notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="&lt;select name=&quot;filter[participation]&quot; id=&quot;filter_participation&quot;&gt;
    &lt;option value=&quot;&quot;&gt;Select a value&lt;/option&gt;
    &lt;option value=&quot;1&quot;&gt;Yes&lt;/option&gt;
    &lt;option selected=&quot;selected&quot; value=&quot;0&quot;&gt;No&lt;/option&gt;
&lt;/select&gt;"><pre class="notranslate"><span class="pl-kos">&lt;</span><span class="pl-ent">select</span> <span class="pl-c1">name</span>="<span class="pl-s">filter[participation]</span>" <span class="pl-c1">id</span>="<span class="pl-s">filter_participation</span>"<span class="pl-kos">&gt;</span>
    <span class="pl-kos">&lt;</span><span class="pl-ent">option</span> <span class="pl-c1">value</span>=""<span class="pl-kos">&gt;</span>Select a value<span class="pl-kos">&lt;/</span><span class="pl-ent">option</span><span class="pl-kos">&gt;</span>
    <span class="pl-kos">&lt;</span><span class="pl-ent">option</span> <span class="pl-c1">value</span>="<span class="pl-s">1</span>"<span class="pl-kos">&gt;</span>Yes<span class="pl-kos">&lt;/</span><span class="pl-ent">option</span><span class="pl-kos">&gt;</span>
    <span class="pl-kos">&lt;</span><span class="pl-ent">option</span> <span class="pl-c1">selected</span>="<span class="pl-s">selected</span>" <span class="pl-c1">value</span>="<span class="pl-s">0</span>"<span class="pl-kos">&gt;</span>No<span class="pl-kos">&lt;/</span><span class="pl-ent">option</span><span class="pl-kos">&gt;</span>
<span class="pl-kos">&lt;/</span><span class="pl-ent">select</span><span class="pl-kos">&gt;</span></pre></div>
<p dir="auto">Actual result:</p>
<div class="highlight highlight-text-html-basic notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="&lt;select name=&quot;filter[participation]&quot; id=&quot;filter_participation&quot;&gt;
    &lt;option value=&quot;1&quot;&gt;Yes&lt;/option&gt;
    &lt;option selected=&quot;selected&quot; value=&quot;&quot;&gt;No&lt;/option&gt;
&lt;/select&gt;"><pre class="notranslate"><span class="pl-kos">&lt;</span><span class="pl-ent">select</span> <span class="pl-c1">name</span>="<span class="pl-s">filter[participation]</span>" <span class="pl-c1">id</span>="<span class="pl-s">filter_participation</span>"<span class="pl-kos">&gt;</span>
    <span class="pl-kos">&lt;</span><span class="pl-ent">option</span> <span class="pl-c1">value</span>="<span class="pl-s">1</span>"<span class="pl-kos">&gt;</span>Yes<span class="pl-kos">&lt;/</span><span class="pl-ent">option</span><span class="pl-kos">&gt;</span>
    <span class="pl-kos">&lt;</span><span class="pl-ent">option</span> <span class="pl-c1">selected</span>="<span class="pl-s">selected</span>" <span class="pl-c1">value</span>=""<span class="pl-kos">&gt;</span>No<span class="pl-kos">&lt;/</span><span class="pl-ent">option</span><span class="pl-kos">&gt;</span>
<span class="pl-kos">&lt;/</span><span class="pl-ent">select</span><span class="pl-kos">&gt;</span></pre></div>
<p dir="auto">Dump of choiceList:</p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://cloud.githubusercontent.com/assets/652505/12809461/ab8548c8-cb1f-11e5-974b-d38b5dd6c519.png"><img src="https://cloud.githubusercontent.com/assets/652505/12809461/ab8548c8-cb1f-11e5-974b-d38b5dd6c519.png" alt="boolean_choice_dump" style="max-width: 100%;"></a></p>
<p dir="auto">As you can see, the placeholder is not rendered. If I add a new empty value in 'choices', I got an empty value in the view plus the placeholder value.</p>