com.vaadin.flow.component.combobox.dataview.ComboBoxDataView Maven / Gradle / Ivy
/*
* Copyright 2000-2024 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.flow.component.combobox.dataview;
import java.util.stream.Stream;
import com.vaadin.flow.component.ComponentEventListener;
import com.vaadin.flow.component.combobox.ComboBoxBase;
import com.vaadin.flow.data.provider.AbstractDataView;
import com.vaadin.flow.data.provider.BackEndDataProvider;
import com.vaadin.flow.data.provider.DataCommunicator;
import com.vaadin.flow.data.provider.DataProvider;
import com.vaadin.flow.data.provider.IdentifierProvider;
import com.vaadin.flow.data.provider.ItemCountChangeEvent;
import com.vaadin.flow.data.provider.ListDataProvider;
import com.vaadin.flow.shared.Registration;
/**
* Implementation of generic data view for ComboBox. This implementation does
* not depend on a certain type of data provider, i.e. whether is it of
* in-memory or backend type. It can be used if the type of data provider is not
* either {@link ListDataProvider} or {@link BackEndDataProvider}.
*
* @param
* the item type
*/
public class ComboBoxDataView extends AbstractDataView {
private final DataCommunicator dataCommunicator;
/**
* Creates a new generic data view for ComboBox and verifies the passed data
* provider is compatible with this data view implementation.
*
* @param dataCommunicator
* the data communicator of the component
* @param comboBox
* the ComboBox
*/
public ComboBoxDataView(DataCommunicator dataCommunicator,
ComboBoxBase comboBox) {
super(dataCommunicator::getDataProvider, comboBox);
this.dataCommunicator = dataCommunicator;
}
/**
* Gets the item at the given index from the data available in the
* ComboBox's server-side.
*
* This method does not take into account the ComboBox client-side
* filtering, since it doesn't change the item count on the server-side, but
* only makes it easier for users to search through the items in the UI.
*
* @param index
* item index number
* @return item on index
* @throws IndexOutOfBoundsException
* requested index is outside of the data set
*/
@Override
public T getItem(int index) {
return ItemFetchHelper.getItem(dataCommunicator, index);
}
@Override
protected Class getSupportedDataProviderType() {
return DataProvider.class;
}
/**
* Gets the items available on the ComboBox's server-side.
*
* This method does not take into account the ComboBox client-side
* filtering, since it doesn't change the item count on the server-side, but
* only makes it easier for users to search through the items in the UI.
*
* @return items available on the server-side
*/
@Override
public Stream getItems() {
return ItemFetchHelper.getItems(dataCommunicator);
}
@Override
public void setIdentifierProvider(
IdentifierProvider identifierProvider) {
super.setIdentifierProvider(identifierProvider);
dataCommunicator.getKeyMapper().setIdentifierGetter(identifierProvider);
}
/**
* {@inheritDoc}
*
* Combo box fires {@link ItemCountChangeEvent} and notifies all the
* listeners added by this method, if the items count changed, for instance,
* due to adding or removing an item(s).
*
* ComboBox's client-side filter change won't fire
* {@link ItemCountChangeEvent}, since it doesn't change the item count on
* the server-side, but only makes it easier for users to search through the
* items in the UI.
*/
@Override
public Registration addItemCountChangeListener(
ComponentEventListener> listener) {
return super.addItemCountChangeListener(listener);
}
}