/*
* Copyright 2016 Red Hat, Inc. and/or its affiliates.
*
* 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 org.uberfire.ext.security.management.client.widgets.management.list;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;
import javax.enterprise.context.Dependent;
import javax.enterprise.inject.Alternative;
import javax.inject.Inject;
import org.uberfire.ext.security.management.client.widgets.popup.LoadingBox;
/**
* <p>Presenter class for listing entities, with automatic pagination feature management.</p>
* <p>Notes:</p>
* <ul>
* <li>
* <p>By default the <code>onChangePage</code> callback method is not fired, it's handled by this class itself.</p>
* </li>
* </ul>
* @since 0.8.0
*/
@Dependent
@Alternative
public class EntitiesPagedList<T> extends EntitiesList<T> {
protected Collection<T> entities;
protected Callback<T> callback;
protected int currentPage = -1;
@Inject
public EntitiesPagedList(LoadingBox loadingBox,
View view) {
super(loadingBox,
view);
}
/* ******************************************************************************************************
PUBLIC PRESENTER API
****************************************************************************************************** */
public void show(final Collection<T> entities,
final Callback<T> callback) {
if (this.currentPage == -1) {
this.currentPage = 1;
}
this.entities = entities;
this.callback = callback;
show();
}
/* ******************************************************************************************************
PROTECTED PRESENTER API FOR IMPL WIDGETS
****************************************************************************************************** */
protected void show() {
if (callback != null && getEntities() != null) {
final int size = getEntities().size();
EntitiesPagedList.this.totalPages = size / pageSize;
final int start = (currentPage - 1) * pageSize;
final boolean hasMorePages = hasMorePages();
final int end = hasMorePages ? (start + pageSize) : size;
final List<T> pageEntities = buildPageEntities(start,
end);
final PaginationConstraints paginationConstraints = buildPaginationConstraints(size);
show(pageEntities,
paginationConstraints,
callback);
}
}
/* ******************************************************************************************************
PROTECTED METHODS FOR INTERNAL PRESENTER LOGIC
****************************************************************************************************** */
@Override
void onGoToFirstPage() {
if (this.currentPage > -1) {
this.currentPage = 1;
show();
} else {
super.onGoToFirstPage();
}
}
@Override
void onGoToPrevPage() {
if (this.currentPage > -1) {
this.currentPage = paginationConstraints.getCurrentPage() - 1;
show();
} else {
super.onGoToPrevPage();
}
}
@Override
void onGoToNextPage() {
if (this.currentPage > -1) {
this.currentPage = paginationConstraints.getCurrentPage() + 1;
show();
} else {
super.onGoToNextPage();
}
}
@Override
void onGoToLastPage() {
if (this.currentPage > -1) {
this.currentPage = totalPages + 1;
show();
} else {
super.onGoToLastPage();
}
}
@Override
public void clear() {
super.clear();
entities = null;
callback = null;
currentPage = -1;
}
protected Collection<T> getEntities() {
return entities;
}
protected List<T> buildPageEntities(final int start,
final int end) {
return new LinkedList<T>(getEntities()).subList(start,
end);
}
protected PaginationConstraints buildPaginationConstraints(final int size) {
final boolean hasMorePages = hasMorePages();
final boolean isNotFirstPage = currentPage > 1;
return new PaginationConstraints() {
@Override
public boolean isFirstPageEnabled() {
return isNotFirstPage;
}
@Override
public boolean isFirstPageVisible() {
return isNotFirstPage;
}
@Override
public boolean isPrevPageEnabled() {
return isNotFirstPage;
}
@Override
public boolean isPrevPageVisible() {
return isNotFirstPage;
}
@Override
public int getCurrentPage() {
return currentPage;
}
@Override
public boolean isNextPageEnabled() {
return hasMorePages;
}
@Override
public boolean isNextPageVisible() {
return hasMorePages;
}
@Override
public boolean isLastPageEnabled() {
return hasMorePages;
}
@Override
public boolean isLastPageVisible() {
return hasMorePages;
}
@Override
public Integer getTotal() {
return size;
}
};
}
protected boolean hasMorePages() {
return currentPage < EntitiesPagedList.this.totalPages;
}
}