Survey: More fixes in the UI

main/survey/fillsurvey.php

@@ -258,8 +258,10 @@ if (!isset($_GET['show'])) {
 	unset($_SESSION['paged_questions']);
 	unset($_SESSION['page_questions_sec']);
 	$paged_questions_sec=array();
-
-	echo '<div id="survey_content" class="survey_content">'.$survey_data['survey_introduction'].'</div>';
+    
+    if (!empty($survey_data['survey_introduction'])) {
+        echo '<div id="survey_content" class="survey_content">'.$survey_data['survey_introduction'].'</div>';
+    }
 	$limit = 0;
 }
 

main/survey/preview.php

@@ -81,7 +81,9 @@ if (api_is_course_admin() || (api_is_course_admin() && $_GET['isStudentView'] ==
 
 	// Displaying the survey introduction
 	if (!isset($_GET['show'])) {
-		echo '<div id="survey_content" class="survey_content">'.$survey_data['survey_introduction'].'</div>';
+        if (!empty($survey_data['survey_introduction'])) {
+            echo '<div id="survey_content" class="survey_content">'.$survey_data['survey_introduction'].'</div>';
+        }
 		$limit = 0;
 	}
 

main/survey/survey.lib.php

@@ -2047,8 +2047,7 @@ class ch_comment extends survey_question {
 	function render_question($form_content) {
 		echo '<div class="survey_question_wrapper">';
 		echo '<div class="survey_question">'.$form_content['survey_question'].'</div>';
-		echo '</div>';
-		echo "\n";
+		echo '</div>';		
 	}
 }