Add role="grid" and aria-multiselectable to grid (#10009)

Also adds aria-selected for grid rows.

6 files changed, 68 insertions, 3 deletions

diff --git a/client/src/main/java/com/vaadin/client/connectors/grid/MultiSelectionModelConnector.java b/client/src/main/java/com/vaadin/client/connectors/grid/MultiSelectionModelConnector.java
index 92b858cb97..79a3cac92b 100644
--- a/client/src/main/java/com/vaadin/client/connectors/grid/MultiSelectionModelConnector.java
+++ b/client/src/main/java/com/vaadin/client/connectors/grid/MultiSelectionModelConnector.java
@@ -121,6 +121,10 @@ public class MultiSelectionModelConnector
             return isSelectionAllowed;
         }
 
+        @Override
+        public boolean isMultiSelectionAllowed() {
+            return true;
+        }
     }
 
     @Override
diff --git a/client/src/main/java/com/vaadin/client/connectors/grid/SingleSelectionModelConnector.java b/client/src/main/java/com/vaadin/client/connectors/grid/SingleSelectionModelConnector.java
index 560ccb2d85..2320edc8e0 100644
--- a/client/src/main/java/com/vaadin/client/connectors/grid/SingleSelectionModelConnector.java
+++ b/client/src/main/java/com/vaadin/client/connectors/grid/SingleSelectionModelConnector.java
@@ -82,6 +82,11 @@ public class SingleSelectionModelConnector
             return isSelectionAllowed;
         }
 
+        @Override
+        public boolean isMultiSelectionAllowed() {
+            return false;
+        }
+
         /**
          * Sets whether it's allowed to deselect the selected row through the
          * UI. Deselection is allowed by default.
diff --git a/client/src/main/java/com/vaadin/client/widget/grid/selection/SelectionModel.java b/client/src/main/java/com/vaadin/client/widget/grid/selection/SelectionModel.java
index 17763b0a94..513ee4949a 100644
--- a/client/src/main/java/com/vaadin/client/widget/grid/selection/SelectionModel.java
+++ b/client/src/main/java/com/vaadin/client/widget/grid/selection/SelectionModel.java
@@ -58,6 +58,11 @@ public interface SelectionModel<T> {
         public boolean isSelectionAllowed() {
             return false;
         }
+
+        @Override
+        public boolean isMultiSelectionAllowed() {
+            return false;
+        }
     }
 
     /**
@@ -116,6 +121,16 @@ public interface SelectionModel<T> {
     boolean isSelectionAllowed();
 
     /**
+     * Checks if the user is allowed to have more than on item selected.
+     * <p>
+     *
+     * @return <code>true</code> if the user is allowed to select multiple items,
+     *         <code>false</code> otherwise
+     * @since 8.2
+     */
+    boolean isMultiSelectionAllowed();
+
+    /**
      * Gets the selected state from a given grid row json object. This is a
      * helper method for grid selection models.
      *
diff --git a/client/src/main/java/com/vaadin/client/widget/treegrid/TreeGrid.java b/client/src/main/java/com/vaadin/client/widget/treegrid/TreeGrid.java
index 016c701deb..cf9d7ea833 100644
--- a/client/src/main/java/com/vaadin/client/widget/treegrid/TreeGrid.java
+++ b/client/src/main/java/com/vaadin/client/widget/treegrid/TreeGrid.java
@@ -45,6 +45,13 @@ public class TreeGrid extends Grid<JsonObject> {
     private String depthStyleNamePrefix;
 
     /**
+     * Creates a new instance.
+     */
+    public TreeGrid() {
+        setAriaRole("treegrid");
+    }
+
+    /**
      * Body updater that adds additional style to each row containing depth
      * information inside the hierarchy.
      */
diff --git a/client/src/main/java/com/vaadin/client/widgets/Escalator.java b/client/src/main/java/com/vaadin/client/widgets/Escalator.java
index a46450fe07..640304e828 100644
--- a/client/src/main/java/com/vaadin/client/widgets/Escalator.java
+++ b/client/src/main/java/com/vaadin/client/widgets/Escalator.java
@@ -6792,6 +6792,16 @@ public class Escalator extends Widget
         return tableWrapper;
     }
 
+    /**
+     * Returns the {@code <table />} element of the grid.
+     *
+     * @return the table element
+     * @since 8.2
+     */
+    public Element getTable() {
+        return getTableWrapper().getFirstChildElement();
+    }
+
     private Element getSubPartElementTableStructure(SubPartArguments args) {
 
         String type = args.getType();
diff --git a/client/src/main/java/com/vaadin/client/widgets/Grid.java b/client/src/main/java/com/vaadin/client/widgets/Grid.java
index e4ceac93f8..81f6756930 100755
--- a/client/src/main/java/com/vaadin/client/widgets/Grid.java
+++ b/client/src/main/java/com/vaadin/client/widgets/Grid.java
@@ -5597,10 +5597,15 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
 
             rowReference.set(rowIndex, rowData, rowElement);
 
-            if (hasData) {
-                setStyleName(rowElement, rowSelectedStyleName,
-                        isSelected(rowData));
+            boolean isSelected = hasData && isSelected(rowData);
+            if (Grid.this.selectionModel.isSelectionAllowed()) {
+                rowElement.setAttribute("aria-selected", String.valueOf(isSelected));
+            } else {
+                rowElement.removeAttribute("aria-selected");
+            }
 
+            if (hasData) {
+                setStyleName(rowElement, rowSelectedStyleName, isSelected);
                 if (rowStyleGenerator != null) {
                     try {
                         String rowStylename = rowStyleGenerator
@@ -6148,6 +6153,7 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
         cellFocusHandler = new CellFocusHandler();
 
         setStylePrimaryName(STYLE_NAME);
+        setAriaRole("grid");
 
         escalator.getHeader().setEscalatorUpdater(createHeaderUpdater());
         escalator.getBody().setEscalatorUpdater(createBodyUpdater());
@@ -6309,6 +6315,17 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
     }
 
     /**
+     * Adds the given role as 'role="$param"' to the {@code <table />} element
+     * of the grid.
+     *
+     * @param role the role param
+     * @since 8.2
+     */
+    protected void setAriaRole(String role){
+        escalator.getTable().setAttribute("role", role);
+    }
+
+    /**
      * Creates the escalator updater used to update the header rows in this
      * grid. The updater is invoked when header rows or columns are added or
      * removed, or the content of existing header cells is changed.
@@ -7971,6 +7988,13 @@ public class Grid<T> extends ResizeComposite implements HasSelectionHandlers<T>,
             setSelectColumnRenderer(null);
         }
 
+        if (this.selectionModel.isMultiSelectionAllowed()) {
+            escalator.getTable().setAttribute("aria-multiselectable", "true");
+        } else if (this.selectionModel.isSelectionAllowed()) {
+            escalator.getTable().setAttribute("aria-multiselectable", "false");
+        } else {
+            escalator.getTable().removeAttribute("aria-multiselectable");
+        }
         // Refresh rendered rows to update selection, if it has changed
         requestRefreshBody();
     }