fix(NcAppSidebar): provide a method to focus active tab with auto ret…

…urn focus

Signed-off-by: Grigorii K. Shartsev <me@shgk.me>

src/components/NcAppSidebar/NcAppSidebar.vue

@@ -864,6 +864,17 @@ export default {
 			this.$refs.header.focus()
 		},
 
+		/**
+		 * Focus the active tab
+		 * @public
+		 */
+		focusActiveTabContent() {
+			// If a tab is focused then probably a new trigger element moved the focus to the sidebar
+			this.preserveElementToReturnFocus()
+
+			this.$refs.tabs.focusActiveTabContent()
+		},
+
 		/**
 		 * Emit name change event to parent component
 		 *

src/components/NcAppSidebarTab/NcAppSidebarTab.vue

@@ -30,8 +30,8 @@
 		:aria-label="isTablistShown() ? undefined : name"
 		:aria-labelledby="isTablistShown() ? `tab-button-${id}` : undefined"
 		class="app-sidebar__tab"
-		tabindex="0"
-		role="tabpanel"
+		:tabindex="isTablistShown() ? 0 : -1"
+		:role="isTablistShown() ? 'tabpanel' : undefined"
 		@scroll="onScroll">
 		<h3 class="hidden-visually">
 			{{ name }}