Refactor : Ajout de conditions dans app.js pour éviter les erreurs

Change-Id: If39a16ea8fa441e559cfae3400da99658897a48e

appli_sf/assets/default/js/app.js

@@ -30,10 +30,16 @@ window.onload = function () {
         header.classList.toggle('is-mobile-nav-open');
     }
 
-    menu_hamburger.addEventListener('click', menuClick, false);
+    if (menu_hamburger) {
+        menu_hamburger.addEventListener('click', menuClick, false);
+    }
 
     // Is Mobile ?
     function checkMobile() {
+        if (!menu_hamburger) {
+            return;
+        }
+
         let mHamburgerStyle = getComputedStyle(menu_hamburger);
 
         if (mHamburgerStyle.display === 'none') {
@@ -51,20 +57,28 @@ window.onload = function () {
     // Changement header au scroll
     let navTop = document.getElementsByClassName('nav-top')[0];
     let navMiddle = document.getElementsByClassName('nav-middle')[0];
-    let styleNavTop = getComputedStyle(navTop);
-    let styleNavMiddle = getComputedStyle(navMiddle);
-    let navHeight = navTop.offsetHeight + parseInt(styleNavTop.marginTop) + parseInt(styleNavTop.marginBottom) +
-        navMiddle.offsetHeight + parseInt(styleNavMiddle.marginTop) + parseInt(styleNavMiddle.marginBottom) + 1;
 
-    isScrolled(header, navTop, navHeight, this);
+    if (navTop) {
+        let styleNavTop = getComputedStyle(navTop);
+        let styleNavMiddle = getComputedStyle(navMiddle);
+        let navHeight = navTop.offsetHeight + parseInt(styleNavTop.marginTop) + parseInt(styleNavTop.marginBottom) +
+            navMiddle.offsetHeight + parseInt(styleNavMiddle.marginTop) + parseInt(styleNavMiddle.marginBottom) + 1;
 
-    window.addEventListener('scroll', function () {
         isScrolled(header, navTop, navHeight, this);
-    });
+
+        window.addEventListener('scroll', function () {
+            isScrolled(header, navTop, navHeight, this);
+        });
+    }
 
     // Responsive bouton "Aide" nav
     function helpButton() {
         let navHelp = document.getElementsByClassName('nav-help')[0];
+
+        if (!navHelp) {
+            return;
+        }
+
         let style = getComputedStyle(navHelp);
         let helpWidth = navHelp.offsetWidth + parseInt(style.paddingLeft) + parseInt(style.paddingRight);
         let helpSpace = (window.innerWidth - 1050) / 2;
@@ -83,6 +97,10 @@ window.onload = function () {
 
     // Margin-top main par rapport à la hauteur de la nav
     function mainMargin() {
+        if (!header) {
+            return;
+        }
+
         let headerHeight = header.offsetHeight;
         let main = document.getElementsByTagName('main')[0];