Error message
Warning: foreach() argument must be of type array|object, null given in Drupal\pollions_custom\Form\PrevnextForm->buildForm() (line 59 of modules/custom/pollions_custom/src/Form/PrevnextForm.php).
Drupal\pollions_custom\Form\PrevnextForm->buildForm(Array, Object) call_user_func_array(Array, Array) (Line: 536) Drupal\Core\Form\FormBuilder->retrieveForm('prev_next_form', Object) (Line: 284) Drupal\Core\Form\FormBuilder->buildForm('Drupal\pollions_custom\Form\PrevnextForm', Object) (Line: 224) Drupal\Core\Form\FormBuilder->getForm('Drupal\pollions_custom\Form\PrevnextForm') (Line: 21) Drupal\pollions_custom\Plugin\Block\PrevnextBlock->build() (Line: 171) Drupal\block\BlockViewBuilder::preRender(Array) call_user_func_array('Drupal\block\BlockViewBuilder::preRender', Array) (Line: 113) Drupal\Core\Render\Renderer->doTrustedCallback('Drupal\block\BlockViewBuilder::preRender', Array, 'Render #pre_render callbacks must be methods of a class that implements \Drupal\Core\Security\TrustedCallbackInterface or be an anonymous function. The callback was %s. See https://www.drupal.org/node/2966725', 'exception', 'Drupal\Core\Render\Element\RenderCallbackInterface') (Line: 870) Drupal\Core\Render\Renderer->doCallback('#pre_render', 'Drupal\block\BlockViewBuilder::preRender', Array) (Line: 432) Drupal\Core\Render\Renderer->doRender(Array) (Line: 504) Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 248) Drupal\Core\Render\Renderer->render(Array) (Line: 475) Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 191) __TwigTemplate_b131b2fc6584c37017e9401591d3f4af->doDisplay(Array, Array) (Line: 360) Twig\Template->yield(Array) (Line: 335) Twig\Template->render(Array) (Line: 38) Twig\TemplateWrapper->render(Array) (Line: 33) twig_render_template('themes/custom/pollions/templates/layout/page--poll--%.html.twig', Array) (Line: 348) Drupal\Core\Theme\ThemeManager->render('page', Array) (Line: 491) Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 248) Drupal\Core\Render\Renderer->render(Array) (Line: 475) Drupal\Core\Template\TwigExtension->escapeFilter(Object, Array, 'html', NULL, 1) (Line: 109) __TwigTemplate_1eb2c6fb2486ac6490bc3a21319b8fb5->doDisplay(Array, Array) (Line: 360) Twig\Template->yield(Array) (Line: 335) Twig\Template->render(Array) (Line: 38) Twig\TemplateWrapper->render(Array) (Line: 33) twig_render_template('themes/custom/pollions/templates/layout/html.html.twig', Array) (Line: 348) Drupal\Core\Theme\ThemeManager->render('html', Array) (Line: 491) Drupal\Core\Render\Renderer->doRender(Array, ) (Line: 248) Drupal\Core\Render\Renderer->render(Array) (Line: 158) Drupal\Core\Render\MainContent\HtmlRenderer->Drupal\Core\Render\MainContent\{closure}() (Line: 638) Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 153) Drupal\Core\Render\MainContent\HtmlRenderer->renderResponse(Array, Object, Object) (Line: 90) Drupal\Core\EventSubscriber\MainContentViewSubscriber->onViewRenderArray(Object, 'kernel.view', Object) call_user_func(Array, Object, 'kernel.view', Object) (Line: 111) Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher->dispatch(Object, 'kernel.view') (Line: 186) Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 76) Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 53) Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48) Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 28) Drupal\Core\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 32) Drupal\big_pipe\StackMiddleware\ContentLength->handle(Object, 1, 1) (Line: 48) Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51) Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 36) Drupal\Core\StackMiddleware\AjaxPageState->handle(Object, 1, 1) (Line: 51) Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object, 1, 1) (Line: 741) Drupal\Core\DrupalKernel->handle(Object) (Line: 19)
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