FormElement: Add Multiselect element

src/FormElement/MultiselectElement.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace ipl\Html\FormElement;
+
+class MultiselectElement extends SelectElement
+{
+    /** @var array Selected values */
+    protected $value = [];
+
+    public function getValueAttribute()
+    {
+        // select elements don't have a value attribute
+        return null;
+    }
+
+    public function getNameAttribute()
+    {
+        return $this->getName() . '[]';
+    }
+
+    public function setValue($value)
+    {
+        $this->value = empty($value) ? [] : (array) $value;
+        $this->valid = null;
+
+        return $this;
+    }
+
+    public function validate()
+    {
+        foreach ($this->getValue() as $value) {
+            $option = $this->getOption($value);
+            if (! $option || $option->getAttributes()->has('disabled')) {
+                $this->valid = false;
+                $this->addMessage(sprintf($this->translate("'%s' is not allowed here"), $value));
+
+                return $this;
+            }
+        }
+
+        BaseFormElement::validate();
+
+        return $this;
+    }
+
+    protected function isSelectedOption($optionValue)
+    {
+        return in_array($optionValue, $this->getValue(), ! is_int($optionValue));
+    }
+
+    protected function assemble()
+    {
+        $this->setAttribute('multiple', true);
+
+        parent::assemble();
+    }
+}

src/FormElement/SelectElement.php

@@ -3,9 +3,12 @@
 namespace ipl\Html\FormElement;
 
 use ipl\Html\Html;
+use ipl\I18n\Translation;
 
 class SelectElement extends BaseFormElement
 {
+    use Translation;
+
     protected $tag = 'select';
 
     /** @var SelectOption[] */
@@ -45,13 +48,13 @@ public function validate()
             )
         ) {
             $this->valid = false;
-            $this->addMessage("'$value' is not allowed here");
-        } elseif ($this->isRequired() && $value === null) {
-            $this->valid = false;
-        } else {
-            parent::validate();
+            $this->addMessage(sprintf($this->translate("'%s' is not allowed here"), $value));
+
+            return $this;
         }
 
+        parent::validate();
+
         return $this;
     }
 
@@ -67,9 +70,10 @@ public function disableOption($value)
         if ($option = $this->getOption($value)) {
             $option->getAttributes()->add('disabled', true);
         }
-        if ($this->getValue() == $value) {
+
+        if ($this->isSelectedOption($value)) {
             $this->valid = false;
-            $this->addMessage("'$value' is not allowed here");
+            $this->addMessage(sprintf($this->translate("'%s' is not allowed here"), $value));
         }
 
         return $this;
@@ -124,20 +128,30 @@ protected function makeOption($value, $label)
         } else {
             $option = new SelectOption($value, $label);
             $option->getAttributes()->registerAttributeCallback('selected', function () use ($option) {
-                $optionValue = $option->getValue();
-
-                return is_int($optionValue)
-                    // The loose comparison is required because PHP casts
-                    // numeric strings to integers if used as array keys
-                    ? $this->getValue() == $optionValue
-                    : $this->getValue() === $optionValue;
+                return $this->isSelectedOption($option->getValue());
             });
             $this->options[$value] = $option;
 
             return $this->options[$value];
         }
     }
 
+    /**
+     * Whether the given option is a selected option
+     *
+     * @param $optionValue
+     *
+     * @return bool
+     */
+    protected function isSelectedOption($optionValue)
+    {
+        return is_int($optionValue)
+            // The loose comparison is required because PHP casts
+            // numeric strings to integers if used as array keys
+            ? $this->getValue() == $optionValue
+            : $this->getValue() === $optionValue;
+    }
+
     protected function assemble()
     {
         $this->addHtml(...array_values($this->optionContent));