Issue #2933183: Support Hijri format for views

src/Plugin/views/field/HijriViewsField.php

+<?php
+
+namespace Drupal\hijri\Plugin\views\field;
+
+use Drupal\views\Plugin\views\field\Date;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\views\ResultRow;
+
+/**
+ * A handler to provide custom displays for Hijri dates.
+ *
+ * @ingroup views_field_handlers
+ *
+ * @ViewsField("hijri_views_field")
+ */
+class HijriViewsField extends Date {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
+    parent::buildOptionsForm($form, $form_state);
+    $hijri_formatter = \Drupal::service('hijri.formatter');
+
+    $form['date_format']['#options']['hijri_full'] = t('Hijri full format: @hijri on @gregorian', [
+      '@hijri' => $hijri_formatter->format(time(), 'custom', 'l j F Y'),
+      '@gregorian' => \Drupal::service('date.formatter')->format(time(), 'custom', 'F j, Y'),
+    ]);
+    $form['date_format']['#options']['hijri_long'] = $this->t('Hijri long format: @date', ['@date' => $hijri_formatter->format(time(), 'long', NULL)]);
+    $form['date_format']['#options']['hijri_medium'] = $this->t('Hijri medium format: @date', ['@date' => $hijri_formatter->format(time(), 'medium', NULL)]);
+    $form['date_format']['#options']['hijri_short'] = $this->t('Hijri short format: @date', ['@date' => $hijri_formatter->format(time(), 'short', NULL)]);
+    $form['date_format']['#options']['hijri_custom'] = $this->t('Hijri custom');
+
+    $form['custom_date_format']['#states']['visible'][] = [
+      ':input[name="options[date_format]"]' => ['value' => 'hijri_custom'],
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function render(ResultRow $values) {
+    $list = [
+      'hijri_long',
+      'hijri_medium',
+      'hijri_short',
+    ];
+    $value = $this->getValue($values);
+    $hijri_formatter = \Drupal::service('hijri.formatter');
+    $format = $this->options['date_format'];
+    if ($format == 'hijri_full') {
+      return t('@hijri on @gregorian', [
+        '@hijri' => $hijri_formatter->format($value, 'custom', 'l j F Y'),
+        '@gregorian' => \Drupal::service('date.formatter')->format($value, 'custom', 'F j, Y'),
+      ]);
+    }
+    elseif (in_array($format, $list)) {
+      $explode = explode("_", $format);
+      return $hijri_formatter->format($value, $explode[1]);
+    }
+    elseif ($format == 'hijri_custom') {
+      $custom_format = $this->options['custom_date_format'];
+      return $hijri_formatter->format($value, $format, $custom_format);
+    }
+
+    return parent::render($values);
+  }
+
+}