From c83d985bac2056956a4962d78a12c9162200e19c Mon Sep 17 00:00:00 2001
From: Tamas Perlaky <tamas@tamas.net>
Date: Thu, 24 May 2018 18:00:58 -0400
Subject: [PATCH 1/3] Added support for centered horizontal tabs.

---
 demo/tabs-basic-demos.html | 11 +++++++++++
 src/vaadin-tabs.html       | 13 +++++++++++++
 2 files changed, 24 insertions(+)

diff --git a/demo/tabs-basic-demos.html b/demo/tabs-basic-demos.html
index 7ee0aa0..aec0108 100644
--- a/demo/tabs-basic-demos.html
+++ b/demo/tabs-basic-demos.html
@@ -28,6 +28,17 @@ <h3>Vertical tabs</h3>
       </template>
     </vaadin-demo-snippet>
 
+    <h3>Centered horizontal tabs</h3>
+    <vaadin-demo-snippet id='tabs-basic-demos-centered-horizontal-tabs'>
+      <template preserve-content>
+        <vaadin-tabs centered>
+          <vaadin-tab>Tab one</vaadin-tab>
+          <vaadin-tab>Tab two</vaadin-tab>
+          <vaadin-tab>Tab three</vaadin-tab>
+        </vaadin-tabs>
+      </template>
+    </vaadin-demo-snippet>
+
     <h3>Scrollable horizontal tabs</h3>
     <vaadin-demo-snippet id='tabs-basic-demos-scrollable-horizontal-tabs'>
       <template preserve-content>
diff --git a/src/vaadin-tabs.html b/src/vaadin-tabs.html
index 779da83..380f19e 100644
--- a/src/vaadin-tabs.html
+++ b/src/vaadin-tabs.html
@@ -36,6 +36,10 @@
         -ms-overflow-style: none;
       }
 
+      :host([orientation="horizontal"][centered]) [part="tabs"] {
+        justify-content: center;
+      }
+
       /* This seems more future-proof than `overflow: -moz-scrollbars-none` which is marked obsolete
          and is no longer guaranteed to work:
          https://developer.mozilla.org/en-US/docs/Web/CSS/overflow#Mozilla_Extensions */
@@ -121,6 +125,7 @@
        * Attribute  | Description | Part name
        * -----------|-------------|------------
        * `orientation` | Tabs disposition, valid values are `horizontal` and `vertical`. | :host
+       * `centered` | Center tabs horizontally. Ignored for vertical tabs, incompatible with scrolling. | :host
        * `overflow` | It's set to `start`, `end`, none or both. | :host
        *
        * See [ThemableMixin – how to apply styles for shadow parts](https://github.com/vaadin/vaadin-themable-mixin/wiki)
@@ -155,6 +160,14 @@
               type: String
             },
 
+            /**
+             * Center tabs horizontally. Ignored for vertical tabs, incompatible with scrolling.
+             */
+            centered: {
+              value: false,
+              type: Boolean
+            },
+
             /**
              * The index of the selected tab.
              */

From 765054f7058f16e30bd0f298a834cc1ef8a8a21f Mon Sep 17 00:00:00 2001
From: Yuriy Yevstihnyeyev <yuriy@vaadin.com>
Date: Wed, 20 Jun 2018 11:46:37 +0300
Subject: [PATCH 2/3] Created centered theme

---
 src/vaadin-tabs.html               | 13 -------------
 theme/lumo/vaadin-tabs-styles.html |  6 ++++++
 2 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/src/vaadin-tabs.html b/src/vaadin-tabs.html
index 380f19e..779da83 100644
--- a/src/vaadin-tabs.html
+++ b/src/vaadin-tabs.html
@@ -36,10 +36,6 @@
         -ms-overflow-style: none;
       }
 
-      :host([orientation="horizontal"][centered]) [part="tabs"] {
-        justify-content: center;
-      }
-
       /* This seems more future-proof than `overflow: -moz-scrollbars-none` which is marked obsolete
          and is no longer guaranteed to work:
          https://developer.mozilla.org/en-US/docs/Web/CSS/overflow#Mozilla_Extensions */
@@ -125,7 +121,6 @@
        * Attribute  | Description | Part name
        * -----------|-------------|------------
        * `orientation` | Tabs disposition, valid values are `horizontal` and `vertical`. | :host
-       * `centered` | Center tabs horizontally. Ignored for vertical tabs, incompatible with scrolling. | :host
        * `overflow` | It's set to `start`, `end`, none or both. | :host
        *
        * See [ThemableMixin – how to apply styles for shadow parts](https://github.com/vaadin/vaadin-themable-mixin/wiki)
@@ -160,14 +155,6 @@
               type: String
             },
 
-            /**
-             * Center tabs horizontally. Ignored for vertical tabs, incompatible with scrolling.
-             */
-            centered: {
-              value: false,
-              type: Boolean
-            },
-
             /**
              * The index of the selected tab.
              */
diff --git a/theme/lumo/vaadin-tabs-styles.html b/theme/lumo/vaadin-tabs-styles.html
index 2fb8b26..7e1ae34 100644
--- a/theme/lumo/vaadin-tabs-styles.html
+++ b/theme/lumo/vaadin-tabs-styles.html
@@ -121,6 +121,12 @@
         margin-left: var(--lumo-space-m);
       }
 
+      /* Centered */
+
+      :host([theme~="centered"][orientation="horizontal"]) [part="tabs"] {
+        justify-content: center;
+      }
+
       /* Small */
 
       :host([theme~="small"]),

From a817ec072fcd6f78df14dca76235c5d643eac341 Mon Sep 17 00:00:00 2001
From: Yuriy Yevstihnyeyev <yuriy@vaadin.com>
Date: Wed, 20 Jun 2018 11:46:50 +0300
Subject: [PATCH 3/3] Add theme centered demo

---
 demo/tabs-basic-demos.html      | 11 -----------
 demo/tabs-lumo-theme-demos.html | 11 +++++++++++
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/demo/tabs-basic-demos.html b/demo/tabs-basic-demos.html
index aec0108..7ee0aa0 100644
--- a/demo/tabs-basic-demos.html
+++ b/demo/tabs-basic-demos.html
@@ -28,17 +28,6 @@ <h3>Vertical tabs</h3>
       </template>
     </vaadin-demo-snippet>
 
-    <h3>Centered horizontal tabs</h3>
-    <vaadin-demo-snippet id='tabs-basic-demos-centered-horizontal-tabs'>
-      <template preserve-content>
-        <vaadin-tabs centered>
-          <vaadin-tab>Tab one</vaadin-tab>
-          <vaadin-tab>Tab two</vaadin-tab>
-          <vaadin-tab>Tab three</vaadin-tab>
-        </vaadin-tabs>
-      </template>
-    </vaadin-demo-snippet>
-
     <h3>Scrollable horizontal tabs</h3>
     <vaadin-demo-snippet id='tabs-basic-demos-scrollable-horizontal-tabs'>
       <template preserve-content>
diff --git a/demo/tabs-lumo-theme-demos.html b/demo/tabs-lumo-theme-demos.html
index a7903a5..d8416ce 100644
--- a/demo/tabs-lumo-theme-demos.html
+++ b/demo/tabs-lumo-theme-demos.html
@@ -111,6 +111,17 @@ <h3>Hide Scroll Buttons</h3>
       </template>
     </vaadin-demo-snippet>
 
+    <h3>Centered</h3>
+    <vaadin-demo-snippet id='tabs-lumo-theme-demos-centered'>
+      <template preserve-content>
+        <vaadin-tabs theme="centered">
+          <vaadin-tab>Tab one</vaadin-tab>
+          <vaadin-tab>Tab two</vaadin-tab>
+          <vaadin-tab>Tab three</vaadin-tab>
+        </vaadin-tabs>
+      </template>
+    </vaadin-demo-snippet>
+
     <h3>Small Size</h3>
     <vaadin-demo-snippet id='tabs-lumo-theme-demos-small-size'>
       <template preserve-content>