Add read-only support for single and multi select views for Grid. (#84)

* Add read-only support for single and multi select views for Grid.

Fixes vaadin/framework8-issues#516

4 files changed, 62 insertions, 11 deletions

diff --git a/server/src/main/java/com/vaadin/ui/components/grid/MultiSelectionModelImpl.java b/server/src/main/java/com/vaadin/ui/components/grid/MultiSelectionModelImpl.java
index f85c781345..9c2b506107 100644
--- a/server/src/main/java/com/vaadin/ui/components/grid/MultiSelectionModelImpl.java
+++ b/server/src/main/java/com/vaadin/ui/components/grid/MultiSelectionModelImpl.java
@@ -324,16 +324,12 @@ public class MultiSelectionModelImpl<T> extends AbstractSelectionModel<T>
 
             @Override
             public void setReadOnly(boolean readOnly) {
-                // TODO support read only in grid ?
-                throw new UnsupportedOperationException(
-                        "Read only mode is not supported for grid.");
+                getState().selectionAllowed = readOnly;
             }
 
             @Override
             public boolean isReadOnly() {
-                // TODO support read only in grid ?
-                throw new UnsupportedOperationException(
-                        "Read only mode is not supported for grid.");
+                return isUserSelectionAllowed();
             }
 
             @Override
@@ -429,6 +425,11 @@ public class MultiSelectionModelImpl<T> extends AbstractSelectionModel<T>
         Objects.requireNonNull(addedItems);
         Objects.requireNonNull(removedItems);
 
+        if (userOriginated && !isUserSelectionAllowed()) {
+            throw new IllegalStateException("Client tried to update selection"
+                    + " although user selection is disallowed");
+        }
+
         // if there are duplicates, some item is both added & removed, just
         // discard that and leave things as was before
         addedItems.removeIf(item -> removedItems.remove(item));
@@ -457,6 +458,10 @@ public class MultiSelectionModelImpl<T> extends AbstractSelectionModel<T>
         }, userOriginated);
     }
 
+    private boolean isUserSelectionAllowed() {
+        return getState(false).selectionAllowed;
+    }
+
     private void doUpdateSelection(Consumer<Set<T>> handler,
             boolean userOriginated) {
         if (getParent() == null) {
diff --git a/server/src/main/java/com/vaadin/ui/components/grid/SingleSelectionModelImpl.java b/server/src/main/java/com/vaadin/ui/components/grid/SingleSelectionModelImpl.java
index ac1edaf576..6db6bfa61c 100644
--- a/server/src/main/java/com/vaadin/ui/components/grid/SingleSelectionModelImpl.java
+++ b/server/src/main/java/com/vaadin/ui/components/grid/SingleSelectionModelImpl.java
@@ -169,6 +169,10 @@ public class SingleSelectionModelImpl<T> extends AbstractSelectionModel<T>
      *            selection
      */
     protected void setSelectedFromClient(String key) {
+        if (!isUserSelectionAllowed()) {
+            throw new IllegalStateException("Client tried to update selection"
+                    + " although user selection is disallowed");
+        }
         if (isKeySelected(key)) {
             return;
         }
@@ -224,6 +228,10 @@ public class SingleSelectionModelImpl<T> extends AbstractSelectionModel<T>
         }
     }
 
+    private boolean isUserSelectionAllowed() {
+        return getState(false).selectionAllowed;
+    }
+
     /**
      * Gets a wrapper for using this grid as a single select in a binder.
      *
@@ -267,15 +275,12 @@ public class SingleSelectionModelImpl<T> extends AbstractSelectionModel<T>
 
             @Override
             public void setReadOnly(boolean readOnly) {
-                // TODO support read only when grid is used in binder ?
-                throw new UnsupportedOperationException(
-                        "Read only is not supported for Grid.");
+                getState().selectionAllowed = readOnly;
             }
 
             @Override
             public boolean isReadOnly() {
-                throw new UnsupportedOperationException(
-                        "Read only is not supported for Grid.");
+                return isUserSelectionAllowed();
             }
         };
     }
diff --git a/server/src/test/java/com/vaadin/tests/components/grid/GridMultiSelectionModelTest.java b/server/src/test/java/com/vaadin/tests/components/grid/GridMultiSelectionModelTest.java
index 3a57311bd7..aa601c67be 100644
--- a/server/src/test/java/com/vaadin/tests/components/grid/GridMultiSelectionModelTest.java
+++ b/server/src/test/java/com/vaadin/tests/components/grid/GridMultiSelectionModelTest.java
@@ -76,6 +76,21 @@ public class GridMultiSelectionModelTest {
         }
     }
 
+    private static class TestMultiSelectionModel
+            extends MultiSelectionModelImpl<Object> {
+
+        public TestMultiSelectionModel() {
+            getState(false).selectionAllowed = false;
+        }
+
+        @Override
+        protected void updateSelection(Set<Object> addedItems,
+                Set<Object> removedItems, boolean userOriginated) {
+            super.updateSelection(addedItems, removedItems, userOriginated);
+        }
+
+    }
+
     @Before
     public void setUp() {
         grid = new Grid<>();
@@ -98,6 +113,13 @@ public class GridMultiSelectionModelTest {
     }
 
     @Test(expected = IllegalStateException.class)
+    public void throwExcpetionWhenSelectionIsDisallowed() {
+        TestMultiSelectionModel model = new TestMultiSelectionModel();
+        model.updateSelection(Collections.emptySet(), Collections.emptySet(),
+                true);
+    }
+
+    @Test(expected = IllegalStateException.class)
     public void selectionModelChanged_usingPreviousSelectionModel_throws() {
         grid.setSelectionMode(SelectionMode.SINGLE);
 
diff --git a/server/src/test/java/com/vaadin/tests/components/grid/GridSingleSelectionModelTest.java b/server/src/test/java/com/vaadin/tests/components/grid/GridSingleSelectionModelTest.java
index 06ceb8bfc3..bae7c9c19b 100644
--- a/server/src/test/java/com/vaadin/tests/components/grid/GridSingleSelectionModelTest.java
+++ b/server/src/test/java/com/vaadin/tests/components/grid/GridSingleSelectionModelTest.java
@@ -48,6 +48,19 @@ public class GridSingleSelectionModelTest {
 
     }
 
+    private static class TestSingleSelectionModel
+            extends SingleSelectionModelImpl<Object> {
+
+        public TestSingleSelectionModel() {
+            getState(false).selectionAllowed = false;
+        }
+
+        @Override
+        protected void setSelectedFromClient(String key) {
+            super.setSelectedFromClient(key);
+        }
+    }
+
     private List<Person> selectionChanges;
     private Grid<Person> grid;
     private SingleSelectionModelImpl<Person> selectionModel;
@@ -65,6 +78,12 @@ public class GridSingleSelectionModelTest {
     }
 
     @Test(expected = IllegalStateException.class)
+    public void throwExceptionWhenSelectionIsDisallowed() {
+        TestSingleSelectionModel model = new TestSingleSelectionModel();
+        model.setSelectedFromClient("foo");
+    }
+
+    @Test(expected = IllegalStateException.class)
     public void selectionModelChanged_usingPreviousSelectionModel_throws() {
         grid.setSelectionMode(SelectionMode.MULTI);