Merge "Put horizontal scrolling on screen, take 3"

polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.html

@@ -149,6 +149,7 @@ limitations under the License.
         box-shadow: 0 1px 3px rgba(0, 0, 0, .3);
         display: block;
         margin: .25em 0 1em;
+        overflow-x: auto;
       }
       .patchSetSelect {
         max-width: 8em;

polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.html

@@ -14,18 +14,19 @@ See the License for the specific language governing permissions and
 limitations under the License.
 -->
 
+<link rel="import" href="../../../bower_components/polymer/polymer.html">
 <link rel="import" href="../../../behaviors/base-url-behavior/base-url-behavior.html">
 <link rel="import" href="../../../behaviors/gr-url-encoding-behavior.html">
 <link rel="import" href="../../../behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.html">
 <link rel="import" href="../../../behaviors/rest-client-behavior/rest-client-behavior.html">
 <link rel="import" href="../../../bower_components/iron-dropdown/iron-dropdown.html">
-<link rel="import" href="../../../bower_components/polymer/polymer.html">
 <link rel="import" href="../../shared/gr-button/gr-button.html">
+<link rel="import" href="../../shared/gr-header/gr-header.html">
 <link rel="import" href="../../shared/gr-rest-api-interface/gr-rest-api-interface.html">
 <link rel="import" href="../../shared/gr-select/gr-select.html">
-<link rel="import" href="../gr-diff/gr-diff.html">
 <link rel="import" href="../gr-diff-cursor/gr-diff-cursor.html">
 <link rel="import" href="../gr-diff-preferences/gr-diff-preferences.html">
+<link rel="import" href="../gr-diff/gr-diff.html">
 <link rel="import" href="../gr-patch-range-select/gr-patch-range-select.html">
 
 <dom-module id="gr-diff-view">
@@ -33,7 +34,14 @@ limitations under the License.
     <style>
       :host {
         background-color: var(--view-background-color);
-        display: block;
+      }
+      gr-diff {
+        border: none;
+      }
+      gr-header {
+        background-color: #fff;
+        border-bottom: 1px #eee solid;
+        z-index: 1;
       }
       header,
       .subHeader {
@@ -177,66 +185,67 @@ limitations under the License.
         }
       }
     </style>
-    <header>
+    <gr-header
-      <h3>
+        keep-on-scroll
-        <a href$="[[_computeChangePath(_changeNum, _patchRange.*, _change.revisions)]]">
+        ready-for-measure="[[!_loading]]">
-          [[_changeNum]]</a><span>:</span>
+      <header>
-        <span>[[_change.subject]]</span>
+        <h3>
-        <span class="dash">—</span>
+          <a href$="[[_computeChangePath(_changeNum, _patchRange.*, _change.revisions)]]">
-        <input id="reviewed"
+            [[_changeNum]]</a><span>:</span>
-               class="reviewed"
+          <span>[[_change.subject]]</span>
-               type="checkbox"
+          <span class="dash">—</span>
-               on-change="_handleReviewedChange"
+          <input id="reviewed"
-               hidden$="[[!_loggedIn]]" hidden>
+                 class="reviewed"
-        <div class="jumpToFileContainer desktop">
+                 type="checkbox"
-          <gr-button link class="dropdown-trigger" id="trigger" on-tap="_showDropdownTapHandler">
+                 on-change="_handleReviewedChange"
-            <span>[[_computeFileDisplayName(_path)]]</span>
+                 hidden$="[[!_loggedIn]]" hidden>
-            <span class="downArrow">&#9660;</span>
+          <div class="jumpToFileContainer desktop">
-          </gr-button>
+            <gr-button link class="dropdown-trigger" id="trigger" on-tap="_showDropdownTapHandler">
-          <!-- *-align="" to disable iron-dropdown's element positioning. -->
+              <span>[[_computeFileDisplayName(_path)]]</span>
-          <iron-dropdown id="dropdown"
+              <span class="downArrow">&#9660;</span>
-              allow-outside-scroll
+            </gr-button>
-              vertical-align=""
+            <!-- *-align="" to disable iron-dropdown's element positioning. -->
-              horizontal-align="">
+            <iron-dropdown id="dropdown"
-            <div class="dropdown-content">
+                allow-outside-scroll
-              <template
+                vertical-align=""
-                  is="dom-repeat"
+                horizontal-align="">
-                  items="[[_fileList]]"
+              <div class="dropdown-content">
-                  as="path"
+                <template
-                  initial-count="75">
+                    is="dom-repeat"
-                <a href$="[[_computeDiffURL(_changeNum, _patchRange.*, path)]]"
+                    items="[[_fileList]]"
-                   selected$="[[_computeFileSelected(path, _path)]]"
+                    as="path"
-                   data-key-nav$="[[_computeKeyNav(path, _path, _fileList)]]"
+                    initial-count="75">
-                   on-tap="_handleFileTap">[[_computeFileDisplayName(path)]]</a>
+                  <a href$="[[_computeDiffURL(_changeNum, _patchRange.*, path)]]"
+                     selected$="[[_computeFileSelected(path, _path)]]"
+                     data-key-nav$="[[_computeKeyNav(path, _path, _fileList)]]"
+                     on-tap="_handleFileTap">[[_computeFileDisplayName(path)]]</a>
+                </template>
+              </div>
+            </iron-dropdown>
+          </div>
+          <div class="mobileJumpToFileContainer mobile">
+            <select on-change="_handleMobileSelectChange">
+              <template is="dom-repeat" items="[[_fileList]]" as="path">
+                <option
+                    value$="[[path]]"
+                    selected$="[[_computeFileSelected(path, _path)]]">
+                  [[_computeTruncatedFileDisplayName(path)]]
+                </option>
               </template>
-            </div>
+            </select>
-          </iron-dropdown>
+          </div>
+        </h3>
+        <div class="navLinks desktop">
+          <a class="navLink"
+             href$="[[_computeNavLinkURL(_path, _fileList, -1, 1)]]">Prev</a>
+          /
+          <a class="navLink"
+             href$="[[_computeUpURL(_changeNum, _patchRange, _change, _change.revisions)]]">Up</a>
+          /
+          <a class="navLink"
+             href$="[[_computeNavLinkURL(_path, _fileList, 1, 1)]]">Next</a>
         </div>
-        <div class="mobileJumpToFileContainer mobile">
+      </header>
-          <select on-change="_handleMobileSelectChange">
-            <template is="dom-repeat" items="[[_fileList]]" as="path">
-              <option
-                  value$="[[path]]"
-                  selected$="[[_computeFileSelected(path, _path)]]">
-                [[_computeTruncatedFileDisplayName(path)]]
-              </option>
-            </template>
-          </select>
-        </div>
-      </h3>
-      <div class="navLinks desktop">
-        <a class="navLink"
-           href$="[[_computeNavLinkURL(_path, _fileList, -1, 1)]]">Prev</a>
-        /
-        <a class="navLink"
-           href$="[[_computeUpURL(_changeNum, _patchRange, _change, _change.revisions)]]">Up</a>
-        /
-        <a class="navLink"
-           href$="[[_computeNavLinkURL(_path, _fileList, 1, 1)]]">Next</a>
-      </div>
-    </header>
-    <div class="loading" hidden$="[[!_loading]]">Loading...</div>
-    <div hidden$="[[_loading]]" hidden>
       <div class="subHeader">
         <div class="patchRangeLeft">
           <gr-patch-range-select
@@ -276,6 +285,9 @@ limitations under the License.
           </span>
         </div>
       </div>
+    </gr-header>
+    <div class="loading" hidden$="[[!_loading]]">Loading...</div>
+    <div hidden hidden$="[[_loading]]">
       <gr-diff-preferences
           id="diffPreferences"
           prefs="{{_prefs}}"
@@ -290,6 +302,8 @@ limitations under the License.
       </div>
       <gr-diff
           id="diff"
+          hidden
+          hidden$="[[_loading]]"
           is-image-diff="{{_isImageDiff}}"
           files-weblinks="{{_filesWeblinks}}"
           change-num="[[_changeNum]]"

polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html

@@ -45,7 +45,6 @@ limitations under the License.
         border-top: 1px solid #eee;
         display: flex;
         font: 12px var(--monospace-font-family);
-        overflow-x: auto;
         will-change: transform;
       }
       .diffContainer.hiddenscroll {

polygerrit-ui/app/elements/gr-app.html

@@ -34,6 +34,7 @@ limitations under the License.
 <link rel="import" href="./settings/gr-cla-view/gr-cla-view.html">
 <link rel="import" href="./settings/gr-registration-dialog/gr-registration-dialog.html">
 <link rel="import" href="./settings/gr-settings-view/gr-settings-view.html">
+<link rel="import" href="./shared/gr-header/gr-header.html">
 <link rel="import" href="./shared/gr-overlay/gr-overlay.html">
 <link rel="import" href="./shared/gr-rest-api-interface/gr-rest-api-interface.html">
 
@@ -47,6 +48,13 @@ limitations under the License.
         min-height: 100%;
         flex-direction: column;
       }
+      gr-header {
+        /**
+         * This one should be greater that the z-index in gr-diff-view
+         * because gr-main-header contains overlay.
+         */
+        z-index: 10;
+      }
       gr-main-header,
       footer {
         color: var(--primary-text-color);
@@ -93,8 +101,10 @@ limitations under the License.
         color: #b71c1c;
       }
     </style>
-    <gr-main-header id="mainHeader" search-query="{{params.query}}">
+    <gr-header>
-    </gr-main-header>
+      <gr-main-header id="mainHeader" search-query="{{params.query}}">
+      </gr-main-header>
+    </gr-header>
     <main>
       <template is="dom-if" if="[[_showChangeListView]]" restamp="true">
         <gr-change-list-view

polygerrit-ui/app/elements/shared/gr-header/gr-header.html

@@ -0,0 +1,46 @@
+<!--
+Copyright (C) 2017 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<link rel="import" href="../../../bower_components/polymer/polymer.html">
+
+<dom-module id="gr-header">
+  <template>
+    <style>
+      :host {
+        display: block;
+        height: var(--header-height);
+        position: relative;
+      }
+      header {
+        background: inherit;
+        border: inherit;
+        height: inherit;
+      }
+      .floating {
+        left: 0;
+        position: fixed;
+        width: 100%;
+        will-change: top;
+      }
+    </style>
+    <header id="header" class$="[[_computeHeaderClass(_headerFloating)]]">
+      <div class="contentWrapper">
+        <content></content>
+      </div>
+    </header>
+  </template>
+  <script src="gr-header.js"></script>
+</dom-module>

polygerrit-ui/app/elements/shared/gr-header/gr-header.js

@@ -0,0 +1,150 @@
+// Copyright (C) 2017 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+(function() {
+  'use strict';
+
+  Polymer({
+    is: 'gr-header',
+
+    properties: {
+      readyForMeasure: {
+        type: Boolean,
+        observer: '_maybeFloatHeader',
+      },
+      keepOnScroll: {
+        type: Boolean,
+        value: false,
+      },
+      _isMeasured: {
+        type: Boolean,
+        value: false,
+      },
+      _topInitial: Number,
+      _topLast: Number,
+      _headerHeight: Number,
+      _headerFloating: {
+        type: Boolean,
+        value: false,
+      },
+    },
+
+    attached() {
+      // Enable content measure unless blocked by param.
+      this.async(() => {
+        if (this.readyForMeasure !== false) {
+          this.readyForMeasure = true;
+        }
+      }, 1);
+      this.listen(window, 'scroll', '_handleScroll');
+      this.listen(window, 'resize', '_handleResize');
+    },
+
+    detached() {
+      this.unlisten(window, 'scroll', '_handleScroll');
+      this.unlisten(window, 'resize', '_handleResize');
+    },
+
+    _computeHeaderClass(headerFloating) {
+      return headerFloating ? 'floating' : '';
+    },
+
+    _getScrollY() {
+      return window.scrollY;
+    },
+
+    _handleResize() {
+      if (this._headerFloating) {
+        this._unfloatHeader();
+      }
+      this.debounce('resize', () => {
+        this._maybeFloatHeader();
+        this._handleScrollDebounced();
+      }, 100);
+    },
+
+    _handleScroll() {
+      this._maybeFloatHeader();
+      this.debounce('scroll', this._handleScrollDebounced);
+    },
+
+    _handleScrollDebounced() {
+      if (!this._headerFloating) {
+        return;
+      }
+      const header = this.$.header;
+      const scrollY = this._topInitial - this._getScrollY();
+      let newTop;
+      if (this.keepOnScroll) {
+        if (scrollY > 0) {
+          // Reposition to imitate natural scrolling.
+          newTop = scrollY;
+        } else {
+          newTop = 0;
+        }
+      } else if (scrollY > -this._headerHeight ||
+          this._topLast < -this._headerHeight) {
+        // Allow to scroll away, but ignore when far behind the edge.
+        newTop = scrollY;
+      } else {
+        newTop = -this._headerHeight;
+      }
+      if (this._topLast !== newTop) {
+        if (newTop === undefined) {
+          header.style.top = '';
+        } else {
+          header.style.top = newTop + 'px';
+        }
+        this._topLast = newTop;
+      }
+    },
+
+    _measure() {
+      if (this._isMeasured) {
+        return; // Already measured.
+      }
+      const rect = this.$.header.getBoundingClientRect();
+      if (rect.height === 0 && rect.width === 0) {
+        return; // Not ready for measurement yet.
+      }
+      const top = document.body.scrollTop + rect.top;
+      this._topInitial = top;
+      this._topLast = top;
+      this._isMeasured = true;
+    },
+
+    _maybeFloatHeader() {
+      if (!this.readyForMeasure) {
+        return;
+      }
+      this._measure();
+      if (!this._headerFloating && this._isMeasured) {
+        this._floatHeader();
+      }
+    },
+
+    _unfloatHeader() {
+      this.customStyle['--header-height'] = '';
+      this._headerFloating = false;
+      this.updateStyles();
+    },
+
+    _floatHeader() {
+      const rect = this.$.header.getBoundingClientRect();
+      this._headerHeight = rect.height;
+      this.customStyle['--header-height'] = rect.height + 'px';
+      this._headerFloating = true;
+      this.updateStyles();
+    },
+  });
+})();

polygerrit-ui/app/elements/shared/gr-header/gr-header_test.html

@@ -0,0 +1,99 @@
+<!DOCTYPE html>
+<!--
+Copyright (C) 2017 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
+<title>gr-header</title>
+
+<script src="../../../bower_components/webcomponentsjs/webcomponents-lite.min.js"></script>
+<script src="../../../bower_components/web-component-tester/browser.js"></script>
+
+<link rel="import" href="gr-header.html">
+
+<script>void(0);</script>
+
+<test-fixture id="basic">
+  <template>
+    <gr-header>
+      <div style="height: 100px"></div>
+    </gr-header>
+  </template>
+</test-fixture>
+
+<script>
+  suite('gr-header', () => {
+    let element;
+    let sandbox;
+
+    setup(() => {
+      element = fixture('basic');
+      sandbox = sinon.sandbox.create();
+    });
+
+    teardown(() => {
+      sandbox.restore();
+    });
+
+    test('header is the height of the content', () => {
+      assert.equal(element.getBoundingClientRect().height, 100);
+    });
+
+    test('scroll triggers _handleScroll', () => {
+      sandbox.stub(element, '_handleScroll');
+      window.dispatchEvent(new CustomEvent('scroll'));
+      assert.isTrue(element._handleScroll.called);
+    });
+
+    suite('_handleScroll', () => {
+      const getHeaderTop = function() {
+        return element.$.header.style.top;
+      };
+
+      const emulateScrollY = function(distance) {
+        element._getScrollY.returns(distance);
+        element._handleScroll();
+        element.flushDebouncer('scroll');
+      };
+
+      setup(() => {
+        element._headerTopInitial = 10;
+        sandbox.stub(element, '_getScrollY').returns(0);
+      });
+
+      test('is debounced', () => {
+        sandbox.stub(element, 'debounce');
+        element._handleScroll();
+        assert.isTrue(element.debounce.called);
+      });
+
+      test('scrolls header along with document', () => {
+        emulateScrollY(20);
+        assert.equal(getHeaderTop(), '-10px');
+      });
+
+      test('does not stick to the top by default', () => {
+        emulateScrollY(150);
+        assert.equal(getHeaderTop(), '-140px');
+      });
+
+      test('sticks to the top if enabled', () => {
+        element.keepOnScroll = true;
+        emulateScrollY(120);
+        assert.equal(getHeaderTop(), '0px');
+      });
+    });
+  });
+</script>