1 files changed, 32 insertions, 0 deletions
diff --git a/app/assets/javascripts/sticky_tabs.js b/app/assets/javascripts/sticky_tabs.js
new file mode 100644
index 00000000000..ec81cfbae0d
--- /dev/null
+++ b/app/assets/javascripts/sticky_tabs.js
@@ -0,0 +1,32 @@
+class StickyTabs {
+  constructor(stickyTabs, unstickyTabs) {
+    this.stickyTabs = stickyTabs;
+    this.unstickyTabs = unstickyTabs;
+
+    this.unstickyTabsHeight = this.unstickyTabs.offsetHeight;
+
+    this.eventListeners = {};
+  }
+
+  bindEvents() {
+    this.eventListeners.handleStickyTabs = this.handleStickyTabs.bind(this);
+
+    document.addEventListener('scroll', this.eventListeners.handleStickyTabs);
+  }
+
+  unbindEvents() {
+    document.removeEventListener('scroll', this.eventListeners.handleStickyTabs);
+  }
+
+  handleStickyTabs() {
+    if (this.unstickyTabs.getBoundingClientRect().top <= this.unstickyTabsHeight) {
+      this.unstickyTabs.classList.add('invisible');
+      this.stickyTabs.classList.remove('hide');
+    } else {
+      this.unstickyTabs.classList.remove('invisible');
+      this.stickyTabs.classList.add('hide');
+    }
+  }
+}
+
+export default StickyTabs;