/*
* Copyright 2000-2016 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.v7.client.connectors;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import com.vaadin.client.ServerConnector;
import com.vaadin.client.data.AbstractRemoteDataSource;
import com.vaadin.client.extensions.AbstractExtensionConnector;
import com.vaadin.shared.Range;
import com.vaadin.shared.data.DataProviderRpc;
import com.vaadin.shared.data.DataRequestRpc;
import com.vaadin.shared.ui.Connect;
import com.vaadin.v7.shared.ui.grid.GridState;
import elemental.json.Json;
import elemental.json.JsonArray;
import elemental.json.JsonObject;
/**
* Connects a Vaadin server-side container data source to a Grid. This is
* currently implemented as an Extension hardcoded to support a specific
* connector type. This will be changed once framework support for something
* more flexible has been implemented.
*
* @since 7.4
* @author Vaadin Ltd
*/
@Connect(com.vaadin.v7.server.communication.data.RpcDataProviderExtension.class)
public class RpcDataSourceConnector extends AbstractExtensionConnector {
/**
* A callback interface to let {@link GridConnector} know that detail
* visibilities might have changed.
*
* @since 7.5.0
* @author Vaadin Ltd
*/
interface DetailsListener {
/**
* A request to verify (and correct) the visibility for a row, given
* updated metadata.
*
* @param rowIndex
* the index of the row that should be checked
* @param row
* the row object to check visibility for
* @see GridState#JSONKEY_DETAILS_VISIBLE
*/
void reapplyDetailsVisibility(int rowIndex, JsonObject row);
}
public class RpcDataSource extends AbstractRemoteDataSource<JsonObject> {
protected RpcDataSource() {
registerRpc(DataProviderRpc.class, new DataProviderRpc() {
@Override
public void setRowData(int firstRow, JsonArray rowArray) {
ArrayList<JsonObject> rows = new ArrayList<JsonObject>(
rowArray.length());
for (int i = 0; i < rowArray.length(); i++) {
JsonObject rowObject = rowArray.getObject(i);
rows.add(rowObject);
}
RpcDataSource.this.setRowData(firstRow, rows);
}
@Override
public void removeRowData(int firstRow, int count) {
RpcDataSource.this.removeRowData(firstRow, count);
}
@Override
public void insertRowData(int firstRow, int count) {
RpcDataSource.this.insertRowData(firstRow, count);
}
@Override
public void resetDataAndSize(int size) {
RpcDataSource.this.resetDataAndSize(size);
}
@Override
public void updateRowData(JsonArray rowArray) {
for (int i = 0; i < rowArray.length(); ++i) {
RpcDataSource.this.updateRowData(rowArray.getObject(i));
}
}
});
}
private DataRequestRpc rpcProxy = getRpcProxy(DataRequestRpc.class);
private DetailsListener detailsListener;
private JsonArray droppedRowKeys = Json.createArray();
@Override
protected void requestRows(int firstRowIndex, int numberOfRows,
RequestRowsCallback<JsonObject> callback) {
if (droppedRowKeys.length() > 0) {
rpcProxy.dropRows(droppedRowKeys);
droppedRowKeys = Json.createArray();
}
/*
* If you're looking at this code because you want to learn how to
* use AbstactRemoteDataSource, please look somewhere else instead.
*
* We're not doing things in the conventional way with the callback
* here since Vaadin doesn't directly support RPC with return
* values. We're instead asking the server to push us some data, and
* when we receive pushed data, we just push it along to the
* underlying cache in the same way no matter if it was a genuine
* push or just a result of us requesting rows.
*/
Range cached = getCachedRange();
rpcProxy.requestRows(firstRowIndex, numberOfRows, cached.getStart(),
cached.length());
/*
* Show the progress indicator if there is a pending data request
* and some of the visible rows are being requested. The RPC in
* itself will not trigger the indicator since it might just fetch
* some rows in the background to fill the cache.
*
* The indicator will be hidden by the framework when the response
* is received (unless another request is already on its way at that
* point).
*/
if (getRequestedAvailability().intersects(
Range.withLength(firstRowIndex, numberOfRows))) {
getConnection().getLoadingIndicator().ensureTriggered();
}
}
@Override
public void ensureAvailability(int firstRowIndex, int numberOfRows) {
super.ensureAvailability(firstRowIndex, numberOfRows);
/*
* We trigger the indicator already at this point since the actual
* RPC will not be sent right away when waiting for the response to
* a previous request.
*
* Only triggering here would not be enough since the check that
* sets isWaitingForData is deferred. We don't want to trigger the
* loading indicator here if we don't know that there is actually a
* request going on since some other bug might then cause the
* loading indicator to not be hidden.
*/
if (isWaitingForData()
&& !Range.withLength(firstRowIndex, numberOfRows)
.isSubsetOf(getCachedRange())) {
getConnection().getLoadingIndicator().ensureTriggered();
}
}
@Override
public String getRowKey(JsonObject row) {
if (row.hasKey(GridState.JSONKEY_ROWKEY)) {
return row.getString(GridState.JSONKEY_ROWKEY);
} else {
return null;
}
}
public RowHandle<JsonObject> getHandleByKey(Object key) {
JsonObject row = Json.createObject();
row.put(GridState.JSONKEY_ROWKEY, (String) key);
return new RowHandleImpl(row, key);
}
@Override
protected void unpinHandle(RowHandleImpl handle) {
// Row data is no longer available after it has been unpinned.
String key = getRowKey(handle.getRow());
super.unpinHandle(handle);
if (!handle.isPinned()) {
if (indexOfKey(key) == -1) {
// Row out of view has been unpinned. drop it
droppedRowKeys.set(droppedRowKeys.length(), key);
}
}
}
void setDetailsListener(DetailsListener detailsListener) {
this.detailsListener = detailsListener;
}
@Override
protected void setRowData(int firstRowIndex, List<JsonObject> rowData) {
super.setRowData(firstRowIndex, rowData);
/*
* Intercepting details information from the data source, rerouting
* them back to the GridConnector (as a details listener)
*/
for (int i = 0; i < rowData.size(); i++) {
detailsListener.reapplyDetailsVisibility(firstRowIndex + i,
rowData.get(i));
}
}
/**
* Updates row data based on row key.
*
* @since 7.6
* @param row
* new row object
*/
protected void updateRowData(JsonObject row) {
int index = indexOfKey(getRowKey(row));
if (index >= 0) {
setRowData(index, Collections.singletonList(row));
}
}
@Override
protected void onDropFromCache(int rowIndex, JsonObject row) {
if (!isPinned(row)) {
droppedRowKeys.set(droppedRowKeys.length(), getRowKey(row));
}
}
@Override
protected boolean canFetchData() {
return isEnabled();
}
}
private final RpcDataSource dataSource = new RpcDataSource();
@Override
protected void extend(ServerConnector target) {
GridConnector gridConnector = (GridConnector) target;
dataSource.setDetailsListener(gridConnector.getDetailsListener());
gridConnector.setDataSource(dataSource);
}
}