Add diff pref whether the diff table header should be auto hidden

Add a new diff preference that allows the user to decide whether the
diff table header with the patch set selection should be automatically
hidden when scrolling down more than half of a page. At the moment
this behaviour cannot be disabled, but some users find it annoying
that the header disappears and that they need to scroll up to be able
to change the patch set selection.

By default the diff table header is automatically hidden as this is
the current behaviour.

Change-Id: I1d65c5058222c924ccaf3276f7d2d83fac7f4d32
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>

Documentation/rest-api-accounts.txt

@@ -1417,7 +1417,7 @@ The `DiffPreferencesInfo` entity contains information about the diff
 preferences of a user.
 
 [options="header",width="50%",cols="1,^1,5"]
-|=====================================
+|===========================================
 |Field Name                    ||Description
 |`context`                     ||
 The number of lines of context when viewing a patch.
@@ -1444,7 +1444,7 @@ Whether Windows EOL/Cr-Lf should be displayed as '\r' in a dotted-line
 box.
 |`show_tabs`                   |not set if `false`|
 Whether tabs should be shown.
-|`show_whitespace_errors`|not set if `false`|
+|`show_whitespace_errors`      |not set if `false`|
 Whether whitespace errors should be shown.
 |`skip_deleted`                |not set if `false`|
 Whether deleted files should be skipped on file switch.
@@ -1454,11 +1454,14 @@ Whether uncommented files should be skipped on file switch.
 Whether syntax highlighting should be enabled.
 |`hide_top_menu`               |not set if `false`|
 If true the top menu header and site header is hidden.
+|`auto_hide_diff_table_header` |not set if `false`|
+If true the diff table header is automatically hidden when
+scrolling down more than half of a page.
 |`hide_line_numbers`           |not set if `false`|
 If true the line numbers are hidden.
 |`tab_size`                    ||
 Number of spaces that should be used to display one tab.
-|=====================================
+|===========================================
 
 [[diff-preferences-input]]
 === DiffPreferencesInput
@@ -1467,7 +1470,7 @@ diff preferences of a user. Fields which are not set will not be
 updated.
 
 [options="header",width="50%",cols="1,^1,5"]
-|=====================================
+|===========================================
 |Field Name                    ||Description
 |`context`                     |optional|
 The number of lines of context when viewing a patch.
@@ -1494,7 +1497,7 @@ Whether Windows EOL/Cr-Lf should be displayed as '\r' in a dotted-line
 box.
 |`show_tabs`                   |optional|
 Whether tabs should be shown.
-|`show_whitespace_errors`|optional|
+|`show_whitespace_errors`      |optional|
 Whether whitespace errors should be shown.
 |`skip_deleted`                |optional|
 Whether deleted files should be skipped on file switch.
@@ -1504,11 +1507,14 @@ Whether uncommented files should be skipped on file switch.
 Whether syntax highlighting should be enabled.
 |`hide_top_menu`               |optional|
 True if the top menu header and site header should be hidden.
+|`auto_hide_diff_table_header` |optional|
+True if the diff table header is automatically hidden when
+scrolling down more than half of a page.
 |`hide_line_numbers`           |optional|
 True if the line numbers should be hidden.
 |`tab_size`                    |optional|
 Number of spaces that should be used to display one tab.
-|=====================================
+|===========================================
 
 [[email-info]]
 === EmailInfo

Documentation/user-review-ui.txt

@@ -1046,6 +1046,11 @@ patch diff is opened, this preference is reset to `Show`.
 +
 Controls whether the top menu is shown.
 
+- `Auto Hide Diff Table Header`:
++
+Controls whether the diff table header should be automatically hidden
+when scrolling down more than half of a page.
+
 [[mark-reviewed]]
 - `Mark Reviewed`:
 +

gerrit-gwtui/src/main/java/com/google/gerrit/client/account/DiffPreferences.java

@@ -35,6 +35,7 @@ public class DiffPreferences extends JavaScriptObject {
     p.showWhitespaceErrors(in.isShowWhitespaceErrors());
     p.syntaxHighlighting(in.isSyntaxHighlighting());
     p.hideTopMenu(in.isHideTopMenu());
+    p.autoHideDiffTableHeader(in.isAutoHideDiffTableHeader());
     p.hideLineNumbers(in.isHideLineNumbers());
     p.expandAllComments(in.isExpandAllComments());
     p.manualReview(in.isManualReview());
@@ -55,6 +56,7 @@ public class DiffPreferences extends JavaScriptObject {
     p.setShowWhitespaceErrors(showWhitespaceErrors());
     p.setSyntaxHighlighting(syntaxHighlighting());
     p.setHideTopMenu(hideTopMenu());
+    p.setAutoHideDiffTableHeader(autoHideDiffTableHeader());
     p.setHideLineNumbers(hideLineNumbers());
     p.setExpandAllComments(expandAllComments());
     p.setManualReview(manualReview());
@@ -82,6 +84,7 @@ public class DiffPreferences extends JavaScriptObject {
   public final native void showWhitespaceErrors(boolean s) /*-{ this.show_whitespace_errors = s }-*/;
   public final native void syntaxHighlighting(boolean s) /*-{ this.syntax_highlighting = s }-*/;
   public final native void hideTopMenu(boolean s) /*-{ this.hide_top_menu = s }-*/;
+  public final native void autoHideDiffTableHeader(boolean s) /*-{ this.auto_hide_diff_table_header = s }-*/;
   public final native void hideLineNumbers(boolean s) /*-{ this.hide_line_numbers = s }-*/;
   public final native void expandAllComments(boolean e) /*-{ this.expand_all_comments = e }-*/;
   public final native void manualReview(boolean r) /*-{ this.manual_review = r }-*/;
@@ -110,6 +113,7 @@ public class DiffPreferences extends JavaScriptObject {
   public final native boolean showWhitespaceErrors() /*-{ return this.show_whitespace_errors || false }-*/;
   public final native boolean syntaxHighlighting() /*-{ return this.syntax_highlighting || false }-*/;
   public final native boolean hideTopMenu() /*-{ return this.hide_top_menu || false }-*/;
+  public final native boolean autoHideDiffTableHeader() /*-{ return this.auto_hide_diff_table_header || false }-*/;
   public final native boolean hideLineNumbers() /*-{ return this.hide_line_numbers || false }-*/;
   public final native boolean expandAllComments() /*-{ return this.expand_all_comments || false }-*/;
   public final native boolean manualReview() /*-{ return this.manual_review || false }-*/;

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/DiffTable.java

@@ -80,6 +80,7 @@ class DiffTable extends Composite {
   private SideBySide2 parent;
   private boolean header;
   private boolean headerVisible;
+  private boolean autoHideHeader;
   private boolean visibleA;
   private ChangeType changeType;
 
@@ -134,7 +135,11 @@ class DiffTable extends Composite {
   }
 
   void setHeaderVisible(boolean show) {
-    headerVisible = show;
+    headerVisible = !autoHideHeader || show;
+    showHeader(headerVisible);
+  }
+
+  private void showHeader(boolean show) {
     UIObject.setVisible(patchSetNavRow, show);
     UIObject.setVisible(diffHeaderRow, show && header);
     if (show) {
@@ -145,6 +150,13 @@ class DiffTable extends Composite {
     parent.resizeCodeMirror();
   }
 
+  void setAutoHideDiffHeader(boolean hide) {
+    autoHideHeader = hide;
+    if (!hide) {
+      showHeader(true);
+    }
+  }
+
   int getHeaderHeight() {
     int h = patchSetSelectBoxA.getOffsetHeight();
     if (header) {
@@ -159,6 +171,7 @@ class DiffTable extends Composite {
 
   void set(DiffPreferences prefs, JsArray<RevisionInfo> list, DiffInfo info) {
     this.changeType = info.change_type();
+    this.autoHideHeader = prefs.autoHideDiffTableHeader();
     patchSetSelectBoxA.setUpPatchSetNav(list, info.meta_a(),
         Natives.asList(info.web_links_a()));
     patchSetSelectBoxB.setUpPatchSetNav(list, info.meta_b(),

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/PreferencesBox.java

@@ -90,6 +90,7 @@ class PreferencesBox extends Composite {
   @UiField ToggleButton leftSide;
   @UiField ToggleButton emptyPane;
   @UiField ToggleButton topMenu;
+  @UiField ToggleButton autoHideDiffTableHeader;
   @UiField ToggleButton manualReview;
   @UiField ToggleButton expandAllComments;
   @UiField ToggleButton renderEntireFile;
@@ -157,6 +158,7 @@ class PreferencesBox extends Composite {
     leftSide.setEnabled(!(prefs.hideEmptyPane()
         && view.diffTable.getChangeType() == ChangeType.ADDED));
     topMenu.setValue(!prefs.hideTopMenu());
+    autoHideDiffTableHeader.setValue(!prefs.autoHideDiffTableHeader());
     manualReview.setValue(prefs.manualReview());
     expandAllComments.setValue(prefs.expandAllComments());
     renderEntireFile.setValue(prefs.renderEntireFile());
@@ -322,6 +324,13 @@ class PreferencesBox extends Composite {
     view.resizeCodeMirror();
   }
 
+  @UiHandler("autoHideDiffTableHeader")
+  void onAutoHideDiffTableHeader(ValueChangeEvent<Boolean> e) {
+    prefs.autoHideDiffTableHeader(!e.getValue());
+    view.setAutoHideDiffHeader(!e.getValue());
+    view.resizeCodeMirror();
+  }
+
   @UiHandler("manualReview")
   void onManualReview(ValueChangeEvent<Boolean> e) {
     prefs.manualReview(e.getValue());

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/PreferencesBox.ui.xml

@@ -249,6 +249,13 @@ limitations under the License.
           <g:downFace><ui:msg>Show</ui:msg></g:downFace>
         </g:ToggleButton></td>
       </tr>
+      <tr>
+        <th><ui:msg>Auto Hide Diff Table Header</ui:msg></th>
+        <td><g:ToggleButton ui:field='autoHideDiffTableHeader'>
+          <g:upFace><ui:msg>Yes</ui:msg></g:upFace>
+          <g:downFace><ui:msg>No</ui:msg></g:downFace>
+        </g:ToggleButton></td>
+      </tr>
       <tr>
         <th><ui:msg>Mark Reviewed</ui:msg></th>
         <td><g:ToggleButton ui:field='manualReview'>

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/SideBySide2.java

@@ -715,6 +715,10 @@ public class SideBySide2 extends Screen {
     });
   }
 
+  void setAutoHideDiffHeader(boolean hide) {
+    diffTable.setAutoHideDiffHeader(hide);
+  }
+
   private void render(DiffInfo diff) {
     header.setNoDiff(diff);
     chunkManager.render(diff);

gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/AccountDiffPreference.java

@@ -92,6 +92,7 @@ public class AccountDiffPreference {
     p.setContext(DEFAULT_CONTEXT);
     p.setManualReview(false);
     p.setHideEmptyPane(false);
+    p.setAutoHideDiffTableHeader(true);
     return p;
   }
 
@@ -156,6 +157,9 @@ public class AccountDiffPreference {
   @Column(id = 20)
   protected boolean hideEmptyPane;
 
+  @Column(id = 21)
+  protected boolean autoHideDiffTableHeader;
+
   protected AccountDiffPreference() {
   }
 
@@ -183,6 +187,7 @@ public class AccountDiffPreference {
     this.hideLineNumbers = p.hideLineNumbers;
     this.renderEntireFile = p.renderEntireFile;
     this.hideEmptyPane = p.hideEmptyPane;
+    this.autoHideDiffTableHeader = p.autoHideDiffTableHeader;
   }
 
   public Account.Id getAccountId() {
@@ -343,4 +348,12 @@ public class AccountDiffPreference {
   public void setHideEmptyPane(boolean hideEmptyPane) {
     this.hideEmptyPane = hideEmptyPane;
   }
+
+  public void setAutoHideDiffTableHeader(boolean hide) {
+    autoHideDiffTableHeader = hide;
+  }
+
+  public boolean isAutoHideDiffTableHeader() {
+    return autoHideDiffTableHeader;
+  }
 }

gerrit-server/src/main/java/com/google/gerrit/server/account/GetDiffPreferences.java

@@ -70,6 +70,7 @@ public class GetDiffPreferences implements RestReadView<AccountResource> {
       info.skipDeleted = p.isSkipDeleted() ? true : null;
       info.skipUncommented = p.isSkipUncommented() ? true : null;
       info.hideTopMenu = p.isHideTopMenu() ? true : null;
+      info.autoHideDiffTableHeader = p.isAutoHideDiffTableHeader() ? true : null;
       info.hideLineNumbers = p.isHideLineNumbers() ? true : null;
       info.syntaxHighlighting = p.isSyntaxHighlighting() ? true : null;
       info.tabSize = p.getTabSize();
@@ -93,6 +94,7 @@ public class GetDiffPreferences implements RestReadView<AccountResource> {
     public Boolean skipUncommented;
     public Boolean syntaxHighlighting;
     public Boolean hideTopMenu;
+    public Boolean autoHideDiffTableHeader;
     public Boolean hideLineNumbers;
     public Boolean renderEntireFile;
     public Boolean hideEmptyPane;

gerrit-server/src/main/java/com/google/gerrit/server/account/SetDiffPreferences.java

@@ -48,6 +48,7 @@ public class SetDiffPreferences implements RestModifyView<AccountResource, Input
     Boolean skipUncommented;
     Boolean syntaxHighlighting;
     Boolean hideTopMenu;
+    Boolean autoHideDiffTableHeader;
     Boolean hideLineNumbers;
     Boolean renderEntireFile;
     Integer tabSize;
@@ -127,6 +128,9 @@ public class SetDiffPreferences implements RestModifyView<AccountResource, Input
       if (input.hideTopMenu != null) {
         p.setHideTopMenu(input.hideTopMenu);
       }
+      if (input.autoHideDiffTableHeader != null) {
+        p.setAutoHideDiffTableHeader(input.autoHideDiffTableHeader);
+      }
       if (input.hideLineNumbers != null) {
         p.setHideLineNumbers(input.hideLineNumbers);
       }

gerrit-server/src/main/java/com/google/gerrit/server/schema/SchemaVersion.java

@@ -32,7 +32,7 @@ import java.util.List;
 /** A version of the database schema. */
 public abstract class SchemaVersion {
   /** The current schema version. */
-  public static final Class<Schema_98> C = Schema_98.class;
+  public static final Class<Schema_99> C = Schema_99.class;
 
   public static class Module extends AbstractModule {
     @Override

gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_99.java

@@ -0,0 +1,25 @@
+// Copyright (C) 2014 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.
+
+package com.google.gerrit.server.schema;
+
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+
+public class Schema_99 extends SchemaVersion {
+  @Inject
+  Schema_99(Provider<Schema_98> prior) {
+    super(prior);
+  }
+}