Add typed NativeSelect and SelectionModel functionality

Change-Id: I3d65d02c34aa6ff0281cae36cfdd8b1166292d7f

client/src/main/java/com/vaadin/client/connectors/components/NativeSelectConnector.java

@@ -0,0 +1,130 @@
+/*
+ * Copyright 2000-2014 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.client.connectors.components;
+
+import java.util.logging.Logger;
+
+import com.google.gwt.event.dom.client.ChangeEvent;
+import com.google.gwt.event.dom.client.ChangeHandler;
+import com.google.gwt.user.client.ui.ListBox;
+import com.vaadin.client.connectors.data.HasSelection;
+import com.vaadin.client.data.DataChangeHandler;
+import com.vaadin.client.data.DataSource;
+import com.vaadin.client.data.selection.SelectionModel;
+import com.vaadin.client.ui.AbstractComponentConnector;
+import com.vaadin.shared.ui.Connect;
+import com.vaadin.ui.components.nativeselect.NativeSelect;
+
+import elemental.json.JsonObject;
+
+@Connect(NativeSelect.class)
+public class NativeSelectConnector extends AbstractComponentConnector implements
+        HasSelection {
+
+    private final class NativeSelectDataChangeHandler implements
+            DataChangeHandler {
+        @Override
+        public void resetDataAndSize(int estimatedNewDataSize) {
+            resetContent();
+        }
+
+        @Override
+        public void dataUpdated(int firstRowIndex, int numberOfRows) {
+            for (int i = 0; i < numberOfRows; ++i) {
+                int index = i + firstRowIndex;
+                JsonObject item = dataSource.getRow(index);
+                getWidget().setItemText(index, item.getString("n"));
+                getWidget().setValue(index, item.getString("k"));
+            }
+        }
+
+        @Override
+        public void dataRemoved(int firstRowIndex, int numberOfRows) {
+            for (int i = 0; i < numberOfRows; ++i) {
+                int index = i + firstRowIndex;
+                getWidget().removeItem(index);
+            }
+        }
+
+        @Override
+        public void dataAvailable(int firstRowIndex, int numberOfRows) {
+            // NO-OP
+        }
+
+        @Override
+        public void dataAdded(int firstRowIndex, int numberOfRows) {
+            if (getWidget().getItemCount() == firstRowIndex) {
+                for (int i = 0; i < numberOfRows; ++i) {
+                    JsonObject item = dataSource.getRow(i + firstRowIndex);
+                    Logger.getLogger("foo").warning(item.toJson());
+                    getWidget().addItem(item.getString("n"),
+                            item.getString("k"));
+                }
+            } else {
+                resetContent();
+            }
+        }
+    }
+
+    private DataSource<JsonObject> dataSource;
+    private SelectionModel selectionModel;
+
+    @Override
+    public ListBox getWidget() {
+        return (ListBox) super.getWidget();
+    }
+
+    @Override
+    protected void init() {
+        super.init();
+
+        getWidget().addChangeHandler(new ChangeHandler() {
+
+            @Override
+            public void onChange(ChangeEvent event) {
+                if (selectionModel == null) {
+                    return;
+                }
+                int index = getWidget().getSelectedIndex();
+                JsonObject selected = dataSource.getRow(index);
+                selectionModel.select(selected);
+            }
+        });
+    }
+
+    @Override
+    public void setDataSource(DataSource<JsonObject> dataSource) {
+        if (this.dataSource != null) {
+            dataSource.setDataChangeHandler(null);
+        }
+        this.dataSource = dataSource;
+        dataSource.setDataChangeHandler(new NativeSelectDataChangeHandler());
+        resetContent();
+    }
+
+    @Override
+    public void setSelectionModel(SelectionModel selectionModel) {
+        this.selectionModel = selectionModel;
+    }
+
+    private void resetContent() {
+        getWidget().clear();
+        for (int i = 0; i < dataSource.size(); ++i) {
+            JsonObject item = dataSource.getRow(i);
+            getWidget().addItem(item.getString("n"), item.getString("k"));
+        }
+    }
+}

client/src/main/java/com/vaadin/client/connectors/data/HasSelection.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2000-2014 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.client.connectors.data;
+
+import com.vaadin.client.data.selection.SelectionModel;
+
+/**
+ * Marker interface for Connectors that have a SelectionModel.
+ */
+public interface HasSelection extends HasDataSource {
+
+    /**
+     * Sets the selection model for this Conenctor.
+     * 
+     * @param selectionModel
+     *            selection model
+     */
+    public void setSelectionModel(SelectionModel selectionModel);
+}

client/src/main/java/com/vaadin/client/connectors/selection/AbstractSelectionConnector.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright 2000-2014 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.client.connectors.selection;
+
+import com.vaadin.client.ServerConnector;
+import com.vaadin.client.connectors.data.HasSelection;
+import com.vaadin.client.data.selection.SelectionModel;
+import com.vaadin.client.extensions.AbstractExtensionConnector;
+import com.vaadin.shared.data.typed.DataProviderConstants;
+
+import elemental.json.JsonObject;
+
+public abstract class AbstractSelectionConnector extends
+        AbstractExtensionConnector {
+
+    @Override
+    protected void extend(ServerConnector target) {
+        if (!(target instanceof HasSelection)) {
+            throw new UnsupportedOperationException(
+                    "SelectionModel extending a Connector without HasDataSource");
+        }
+        // TODO: Provide SelectionModel API
+        // TODO: Should this use "Registration" approach for easy and safe
+        // removal?
+        ((HasSelection) target).setSelectionModel(createSelectionModel());
+    }
+
+    /**
+     * Creates a selection model object to be used by the Connector.
+     * 
+     * @return created selection model
+     */
+    protected abstract SelectionModel createSelectionModel();
+
+    protected static String getKey(JsonObject item) {
+        return item.getString(DataProviderConstants.KEY);
+    }
+
+    protected static boolean jsonEquals(JsonObject a, JsonObject b) {
+        final String key = DataProviderConstants.KEY;
+        if (a != null && b != null) {
+            if (a.hasKey(key) && b.hasKey(key)) {
+                return a.getString(key).equals(b.getString(key));
+            }
+        }
+        return a == b;
+    }
+}

client/src/main/java/com/vaadin/client/connectors/selection/NullSelectionConnector.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2000-2014 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.client.connectors.selection;
+
+import com.vaadin.client.ServerConnector;
+import com.vaadin.client.connectors.data.HasSelection;
+import com.vaadin.client.data.selection.SelectionModel;
+import com.vaadin.client.data.selection.SelectionModel.Single;
+import com.vaadin.server.communication.data.typed.SelectionModel.NullSelection;
+import com.vaadin.shared.ui.Connect;
+
+import elemental.json.JsonObject;
+
+@Connect(NullSelection.class)
+public class NullSelectionConnector extends AbstractSelectionConnector {
+
+    @Override
+    protected void extend(ServerConnector target) {
+        if (target instanceof HasSelection) {
+            super.extend(target);
+        }
+    }
+
+    @Override
+    protected SelectionModel createSelectionModel() {
+        return new SelectionModel() {
+
+            @Override
+            public void select(JsonObject item) {
+            }
+
+            @Override
+            public void deselect(JsonObject item) {
+            }
+
+            @Override
+            public boolean isSelected(JsonObject item) {
+                return false;
+            }
+        };
+    }
+}

client/src/main/java/com/vaadin/client/connectors/selection/SingleSelectionConnector.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2000-2014 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.client.connectors.selection;
+
+import com.vaadin.client.data.selection.SelectionModel;
+import com.vaadin.client.data.selection.SelectionModel.Single;
+import com.vaadin.shared.data.selection.SelectionServerRpc;
+import com.vaadin.shared.ui.Connect;
+
+import elemental.json.JsonObject;
+
+@Connect(com.vaadin.server.communication.data.typed.SingleSelection.class)
+public class SingleSelectionConnector extends AbstractSelectionConnector {
+
+    public static class SingleSelection implements SelectionModel, Single {
+
+        private JsonObject value;
+        private SelectionServerRpc rpc;
+
+        public SingleSelection(SelectionServerRpc rpc) {
+            this.rpc = rpc;
+        }
+
+        @Override
+        public void select(JsonObject item) {
+            if (item != null && !jsonEquals(value, item)) {
+                rpc.select(getKey(item));
+                value = item;
+            }
+        }
+
+        @Override
+        public void deselect(JsonObject item) {
+            if (item != null && jsonEquals(value, item)) {
+                rpc.deselect(getKey(item));
+                value = null;
+            }
+        }
+
+        @Override
+        public boolean isSelected(JsonObject item) {
+            return jsonEquals(value, item);
+        }
+    }
+
+    @Override
+    protected SelectionModel createSelectionModel() {
+        return new SingleSelection(getRpcProxy(SelectionServerRpc.class));
+    }
+
+    @Override
+    public void onUnregister() {
+        super.onUnregister();
+    }
+
+}

client/src/main/java/com/vaadin/client/data/selection/SelectionModel.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2000-2014 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.client.data.selection;
+
+import elemental.json.JsonObject;
+
+public interface SelectionModel {
+
+    public interface Single {
+    }
+
+    public interface Multi {
+    }
+
+    /**
+     * Selects the given item. Some selection models will deselect items if
+     * needed.
+     */
+    void select(JsonObject item);
+
+    /**
+     * Deselects the given item. Some selection model can prevent this.
+     */
+    void deselect(JsonObject item);
+
+    /**
+     * Gets the current state of selection for given item.
+     * 
+     * @return {@code true} if selected; {@code false} if not
+     */
+    boolean isSelected(JsonObject item);
+}

server/src/main/java/com/vaadin/server/communication/data/typed/AbstractSelectionModel.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2000-2014 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.server.communication.data.typed;
+
+import com.vaadin.server.AbstractClientConnector;
+import com.vaadin.server.AbstractExtension;
+import com.vaadin.server.Extension;
+import com.vaadin.ui.Component;
+import com.vaadin.ui.components.Listing;
+
+/**
+ * Abstract base class for {@link SelectionModel}s.
+ * 
+ * @param <T>
+ *            type of selected data
+ */
+public abstract class AbstractSelectionModel<T> extends AbstractExtension
+        implements SelectionModel<T> {
+
+    private Listing<T> parent;
+
+    @Override
+    public void setParentListing(Listing<T> target) {
+        if (target instanceof Component && target instanceof Listing
+                && target instanceof AbstractClientConnector) {
+            super.extend((AbstractClientConnector) target);
+            parent = target;
+        } else {
+            throw new IllegalArgumentException(
+                    "Extended object was not suitable for a SelectionModel");
+        }
+    }
+
+    protected final Listing<T> getParentListing() {
+        return parent;
+    }
+
+    protected final DataKeyMapper<T> getKeyMapper() {
+        for (Extension e : ((Component) parent).getExtensions()) {
+            if (e instanceof DataProvider) {
+                return ((DataProvider<T>) e).getKeyMapper();
+            }
+        }
+        return null;
+    }
+
+    protected final T getData(String key) {
+        DataKeyMapper<T> keyMapper = getKeyMapper();
+        if (keyMapper != null) {
+            return keyMapper.get(key);
+        }
+        return null;
+    }
+}

server/src/main/java/com/vaadin/server/communication/data/typed/SelectionModel.java

@@ -22,7 +22,10 @@ import java.util.List;
 
 import com.vaadin.event.handler.Handler;
 import com.vaadin.event.handler.Registration;
+import com.vaadin.server.Extension;
+import com.vaadin.ui.Component;
 import com.vaadin.ui.components.HasValue;
+import com.vaadin.ui.components.Listing;
 
 /**
  * Generic selection model interface.
@@ -31,7 +34,7 @@ import com.vaadin.ui.components.HasValue;
  * @param <T>
  *            type of selected values
  */
-public interface SelectionModel<T> extends Serializable {
+public interface SelectionModel<T> extends Serializable, Extension {
 
     /**
      * Selection model for selection a single value.
@@ -59,14 +62,27 @@ public interface SelectionModel<T> extends Serializable {
      */
     Collection<T> getSelected();
 
+    /**
+     * Add this extension to the target listing component. SelectionModel can
+     * only extend {@link Component}s that implement {@link Listing} interface.
+     * This method should only be called from a listing component when changing
+     * the selection model.
+     *
+     * @param target
+     *            listing component to extend.
+     *
+     * @throws IllegalArgumentException
+     */
+    void setParentListing(Listing<T> target);
+
     /**
      * Dummy selection model.
      * 
      * @param <T>
      *            selected data type
      */
-    public static class NullSelectionModel<T> implements
-            SelectionModel.Single<T> {
+    public static class NullSelection<T> extends AbstractSelectionModel<T>
+            implements SelectionModel.Single<T> {
 
         @Override
         public void setValue(T value) {

server/src/main/java/com/vaadin/server/communication/data/typed/SingleSelection.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2000-2014 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.server.communication.data.typed;
+
+import java.util.Collection;
+import java.util.Collections;
+
+import com.vaadin.event.handler.Handler;
+import com.vaadin.event.handler.Registration;
+import com.vaadin.server.communication.data.typed.SelectionModel.Single;
+import com.vaadin.shared.data.selection.SelectionServerRpc;
+
+/**
+ * {@link SelectionModel} for selecting a single value.
+ * 
+ * @param <T>
+ *            type of selected data
+ */
+public class SingleSelection<T> extends AbstractSelectionModel<T> implements
+        Single<T> {
+
+    public SingleSelection() {
+        registerRpc(new SelectionServerRpc() {
+
+            @Override
+            public void select(String key) {
+                setValue(getData(key));
+            }
+
+            @Override
+            public void deselect(String key) {
+                if (getData(key).equals(value)) {
+                    setValue(null);
+                }
+            }
+        });
+    }
+
+    private T value = null;
+
+    @Override
+    public Collection<T> getSelected() {
+        if (value != null) {
+            return Collections.singleton(value);
+        } else {
+            return Collections.emptySet();
+        }
+    }
+
+    @Override
+    public void setValue(T value) {
+        if (this.value != value) {
+            this.value = value;
+            // TODO: fire event
+        }
+    }
+
+    @Override
+    public T getValue() {
+        return value;
+    }
+
+    @Override
+    public Registration onChange(Handler<T> handler) {
+        return () -> {
+            // TODO: Event registration
+        };
+    }
+}

server/src/main/java/com/vaadin/ui/components/nativeselect/NativeSelect.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright 2000-2014 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.ui.components.nativeselect;
+
+import java.util.function.Function;
+
+import com.vaadin.server.communication.data.typed.DataProvider;
+import com.vaadin.server.communication.data.typed.DataSource;
+import com.vaadin.server.communication.data.typed.SelectionModel;
+import com.vaadin.server.communication.data.typed.SingleSelection;
+import com.vaadin.server.communication.data.typed.TypedDataGenerator;
+import com.vaadin.ui.AbstractComponent;
+import com.vaadin.ui.components.Listing;
+
+import elemental.json.JsonObject;
+
+public class NativeSelect<T> extends AbstractComponent implements Listing<T> {
+
+    private DataSource<T> dataSource;
+    private DataProvider<T> dataProvider;
+    private SelectionModel<T> selectionModel;
+    private Function<T, String> nameProvider = T::toString;
+
+    public NativeSelect() {
+        internalSetSelectionModel(new SingleSelection<>());
+    }
+
+    public NativeSelect(DataSource<T> dataSource) {
+        this();
+        internalSetDataSource(dataSource);
+    }
+
+    @Override
+    public void setDataSource(DataSource<T> data) {
+        internalSetDataSource(data);
+    }
+
+    private void internalSetDataSource(DataSource<T> data) {
+        if (dataProvider != null) {
+            dataProvider.remove();
+            dataProvider = null;
+        }
+        dataSource = data;
+        if (dataSource != null) {
+            dataProvider = DataProvider.create(dataSource, this);
+            dataProvider.addDataGenerator(new TypedDataGenerator<T>() {
+
+                @Override
+                public void generateData(T data, JsonObject jsonObject) {
+                    jsonObject.put("n", nameProvider.apply(data));
+                }
+
+                @Override
+                public void destroyData(T data) {
+                }
+            });
+        }
+    }
+
+    @Override
+    public DataSource<T> getDataSource() {
+        return dataSource;
+    }
+
+    @Override
+    public SelectionModel<T> getSelectionModel() {
+        return selectionModel;
+    }
+
+    @Override
+    public void setSelectionModel(SelectionModel<T> model) {
+        internalSetSelectionModel(model);
+    }
+
+    private void internalSetSelectionModel(SelectionModel<T> model) {
+        if (selectionModel != null) {
+            selectionModel.remove();
+        }
+        selectionModel = model;
+        if (model != null) {
+            model.setParentListing(this);
+        }
+    }
+
+}

shared/src/main/java/com/vaadin/shared/data/selection/SelectionServerRpc.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2000-2014 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.shared.data.selection;
+
+import com.vaadin.shared.communication.ServerRpc;
+
+/**
+ * Simple API for SelectionModel client to server communication
+ */
+public interface SelectionServerRpc extends ServerRpc {
+
+    /**
+     * Select an item based on it's key.
+     * 
+     * @param key
+     *            key of item
+     */
+    void select(String key);
+
+    /**
+     * Deselect an item based on it's key.
+     * 
+     * @param key
+     *            key of item
+     */
+    void deselect(String key);
+}

uitest/src/main/java/com/vaadin/tests/databinding/ListingTestUI.java

@@ -0,0 +1,48 @@
+package com.vaadin.tests.databinding;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.stream.Stream;
+
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.server.communication.data.typed.AbstractDataSource;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Notification;
+import com.vaadin.ui.components.nativeselect.NativeSelect;
+
+public class ListingTestUI extends AbstractTestUI {
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        final List<String> options = createOptions();
+        NativeSelect<String> select = new NativeSelect<>(
+                new AbstractDataSource<String>() {
+
+                    @Override
+                    public void save(String data) {
+                    }
+
+                    @Override
+                    public void remove(String data) {
+                    }
+
+                    @Override
+                    public Iterator<String> iterator() {
+                        return options.iterator();
+                    }
+                });
+        addComponent(select);
+
+        addComponent(new Button("Notify", e -> select.getSelectionModel()
+                .getSelected().forEach(s -> Notification.show(s))));
+    }
+
+    private List<String> createOptions() {
+        List<String> options = new ArrayList<>();
+        Stream.of(1, 2, 3, 4, 5).map(i -> "Option " + i).forEach(options::add);
+        return options;
+    }
+
+}