add Grid.Column#get/setAssistiveCaption (#10219)

* add Grid#Column#get/setAssistiveCaption

* fix test and update doc

* move testGridAssistiveCaption to GridTest

* delete test file

* delete test file

* Delete GridAssistiveCaptionTest.java

* Create GridAssistiveCaptionTest

* Create GridAssistiveCaption

* Rename GridAssistiveCaption to GridAssistiveCaption.java

* Rename GridAssistiveCaptionTest to GridAssistiveCaptionTest.java

* Reformat using eclipse

client/src/main/java/com/vaadin/client/connectors/grid/ColumnConnector.java

@@ -98,6 +98,11 @@ public class ColumnConnector extends AbstractExtensionConnector {
         column.setHeaderCaption(getState().caption);
     }
 
+    @OnStateChange("assistiveCaption")
+    void updateAssistiveCaption() {
+        column.setAssistiveCaption(getState().assistiveCaption);
+    }
+
     @OnStateChange("sortable")
     void updateSortable() {
         column.setSortable(getState().sortable);

client/src/main/java/com/vaadin/client/widgets/Grid.java

@@ -26,6 +26,7 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
+import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
 import java.util.TreeMap;
@@ -4722,6 +4723,8 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
 
         private String headerCaption = "";
 
+        private String assistiveCaption = null;
+
         private String hidingToggleCaption = null;
 
         private double minimumWidthPx = GridConstants.DEFAULT_MIN_WIDTH;
@@ -4836,6 +4839,36 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
             return headerCaption;
         }
 
+        /**
+         * Sets the header aria-label for this column.
+         *
+         * @param caption
+         *            The header aria-label for this column
+         * @return the column itself
+         *
+         * @since
+         */
+        public Column<C, T> setAssistiveCaption(String caption) {
+            if (!Objects.equals(this.assistiveCaption, caption)) {
+                this.assistiveCaption = caption;
+                if (grid != null) {
+                    grid.getHeader().requestSectionRefresh();
+                }
+            }
+
+            return this;
+        }
+        /**
+         * Returns the current header aria-label for this column.
+         *
+         * @return the header aria-label string
+         *
+         * @since
+         */
+        public String getAssistiveCaption() {
+            return assistiveCaption;
+        }
+
         private void updateHeader() {
             HeaderRow row = grid.getHeader().getDefaultRow();
             if (row != null) {
@@ -5730,6 +5763,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
 
                 // Decorate default row with sorting indicators
                 if (staticRow instanceof HeaderRow) {
+                    addAriaLabelToHeaderRow(cell);
                     addSortingIndicatorsToHeaderRow((HeaderRow) staticRow,
                             cell);
                 }
@@ -5954,8 +5988,20 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
             }
         }
 
-        private void addSortingIndicatorsToHeaderRow(HeaderRow headerRow,
-                FlyweightCell cell) {
+        private void addAriaLabelToHeaderRow(FlyweightCell cell) {
+
+            Element cellElement = cell.getElement();
+
+            final Column<?, T> column = getVisibleColumn(cell.getColumn());
+
+            if (column.getAssistiveCaption() != null) {
+                cellElement.setAttribute("aria-label", column.getAssistiveCaption());
+            } else {
+                cellElement.removeAttribute("aria-label");
+            }
+        }
+
+        private void addSortingIndicatorsToHeaderRow(HeaderRow headerRow, FlyweightCell cell) {
 
             Element cellElement = cell.getElement();
 

server/src/main/java/com/vaadin/ui/Grid.java

@@ -1202,6 +1202,36 @@ public class Grid<T> extends AbstractListing<T> implements HasComponents,
             return getState(false).sortable;
         }
 
+        /**
+         * Sets the header aria-label for this column.
+         *
+         * @param caption
+         *            the header aria-label, null removes
+         *            the aria-label from this column
+         *
+         * @return this column
+         *
+         * @since
+         */
+        public Column<T, V> setAssistiveCaption(String caption) {
+            if (Objects.equals(caption, getAssistiveCaption())) {
+                return this;
+            }
+            getState().assistiveCaption = caption;
+            return this;
+        }
+
+        /**
+         * Gets the header caption for this column.
+         *
+         * @return header caption
+         *
+         * @since
+         */
+        public String getAssistiveCaption() {
+            return getState(false).assistiveCaption;
+        }
+
         /**
          * Sets the header caption for this column.
          *
@@ -2131,6 +2161,10 @@ public class Grid<T> extends AbstractListing<T> implements HasComponents,
                 setHidingToggleCaption(DesignAttributeHandler.readAttribute(
                         "hiding-toggle-caption", attributes, String.class));
             }
+            if (design.hasAttr("assistive-caption")) {
+                setAssistiveCaption(DesignAttributeHandler.readAttribute(
+                        "assistive-caption", attributes, String.class));
+            }
 
             // Read size info where necessary.
             if (design.hasAttr("width")) {

server/src/test/java/com/vaadin/tests/server/component/grid/GridTest.java

@@ -79,6 +79,13 @@ public class GridTest {
                 .setId("randomColumnId");
     }
 
+    @Test
+    public void testGridAssistiveCaption() {
+        assertEquals(null, fooColumn.getAssistiveCaption());
+        fooColumn.setAssistiveCaption("Press Enter to sort.");
+        assertEquals("Press Enter to sort.", fooColumn.getAssistiveCaption());
+    }
+
     @Test
     public void testCreateGridWithDataCommunicator() {
         DataCommunicator<String> specificDataCommunicator = new DataCommunicator<>();

shared/src/main/java/com/vaadin/shared/ui/grid/ColumnState.java

@@ -30,6 +30,9 @@ public class ColumnState extends AbstractGridExtensionState {
     public boolean sortable = false;
     public boolean editable = false;
 
+    /** The assistive device caption for the column. */
+    public String assistiveCaption;
+
     /** The caption for the column hiding toggle. */
     public String hidingToggleCaption;
 

uitest/src/main/java/com/vaadin/tests/components/grid/GridAssistiveCaption.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2000-2017 Vaadin Ltd.
+ *
+ * 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.vaadin.tests.components.grid;
+
+import com.vaadin.data.ValueProvider;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Grid;
+
+public class GridAssistiveCaption extends AbstractTestUI {
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        Grid<String> grid = new Grid<>();
+        grid.addColumn(ValueProvider.identity());
+        grid.setItems("a", "b");
+        addComponent(grid);
+
+        addComponent(new Button("addAssistiveCaption", event -> {
+            grid.getColumns().get(0).setAssistiveCaption("Press Enter to sort.");
+        }));
+        addComponent(new Button("removeAssistiveCaption", event -> {
+            grid.getColumns().get(0).setAssistiveCaption(null);
+        }));
+    }
+}

uitest/src/test/java/com/vaadin/tests/components/grid/GridAssistiveCaptionTest.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2000-2017 Vaadin Ltd.
+ *
+ * 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.vaadin.tests.components.grid;
+
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.Test;
+
+import com.vaadin.testbench.elements.ButtonElement;
+import com.vaadin.testbench.elements.GridElement;
+import com.vaadin.tests.tb3.SingleBrowserTest;
+
+public class GridAssistiveCaptionTest extends SingleBrowserTest {
+
+    @Test
+    public void checkGridAriaLabel() {
+        openTestURL();
+
+        GridElement.GridCellElement headerCell = $(GridElement.class).first()
+                .getHeaderCell(0, 0);
+
+        // default grid has no aria-label
+        assertNull("Column should not contain aria-label",
+                headerCell.getAttribute("aria-label"));
+
+        $(ButtonElement.class).caption("addAssistiveCaption").first().click();
+        assertTrue("Column should contain aria-label", headerCell
+                .getAttribute("aria-label").equals("Press Enter to sort."));
+
+        $(ButtonElement.class).caption("removeAssistiveCaption").first()
+                .click();
+        assertNull("Column should not contain aria-label",
+                headerCell.getAttribute("aria-label"));
+    }
+}