Merge branch 'master' into feature/NEOV-198-template-support

cosmoz-tabbable-behavior.html

@@ -179,9 +179,9 @@
 			if (index > -1) {
 				this.debounce('select-resize', this.notifyResize);
 
-				if (!item._previouslySelected) {
+				if (!item.isActive) {
 					this.fire('tab-first-select', {}, opts);
-					item._previouslySelected = true;
+					item.isActive = true;
 				}
 				this.fire('tab-select', {}, opts);
 			}

cosmoz-tabbed-behavior.html

@@ -42,6 +42,16 @@
 				observer: '_animatedSelectedChanged'
 			},
 
+			/**
+			 * Is true when the item has been selected at least once.
+			 */
+			isActive: {
+				type: Boolean,
+				value: false,
+				reflectToAttribute: true,
+				notify: true
+			},
+
 			/**
 			 * Accordion mode element state, true if it is in accordion mode.
 			 * Should be forwarded by a `Cosmoz.TabbableBehavior` ancestor
@@ -107,6 +117,10 @@
 			this._onSelectedTransitionEnd = this._onSelectedTransitionEnd.bind(this);
 		},
 
+		detached() {
+			this.isActive = false;
+		},
+
 		get animated() {
 			return this.accordion;
 		},

test/basic.html

@@ -56,6 +56,10 @@
 					assert.equal(tabs.selectedAttribute, 'is-selected');
 				});
 
+				test('first tab isActive', () => {
+					assert.isTrue(tabs.items[0].isActive);
+				});
+
 				test('not accordion', () => {
 					assert.isFalse(tabs.accordion);
 				});