// Copyright 2007, 2008 The Apache Software Foundation
//
// 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.apache.tapestry.corelib.components;
import org.apache.tapestry.ComponentAction;
import org.apache.tapestry.annotations.Environmental;
import org.apache.tapestry.annotations.Parameter;
import org.apache.tapestry.beaneditor.PropertyModel;
import org.apache.tapestry.grid.GridConstants;
import org.apache.tapestry.grid.GridDataSource;
import org.apache.tapestry.grid.GridModelProvider;
import org.apache.tapestry.internal.TapestryInternalUtils;
import org.apache.tapestry.ioc.internal.util.CollectionFactory;
import org.apache.tapestry.services.FormSupport;
import java.util.List;
/**
* Renders out a series of rows within the table.
* <p/>
* Inside a {@link Form}, a series of row index numbers are stored into the form ( {@linkplain FormSupport#store(Object,
* ComponentAction) as ComponentActions}). This is not ideal ... in a situation where the data set can shift between the
* form render and the form submission, this can cause unexpected results, including applying changes to the wrong
* objects.
*/
public class GridRows
{
private int _startRow;
static class SetupForRow implements ComponentAction<GridRows>
{
private static final long serialVersionUID = -3216282071752371975L;
private final int _rowIndex;
public SetupForRow(int rowIndex)
{
_rowIndex = rowIndex;
}
public void execute(GridRows component)
{
component.setupForRow(_rowIndex);
}
}
/**
* The column which is currently being sorted. This value is the column's {@link PropertyModel#getId() id}, not its
* {@link PropertyModel#getPropertyName() name}. This parameter may be null, in which case no column is being used
* for sorting.
*/
@Parameter(required = true)
private String _sortColumnId;
/**
* If true, then the sort is ascending (A - Z), if false the descending (Z - A).
*/
@Parameter(required = true)
private boolean _sortAscending;
/**
* Parameter used to set the CSS class for each row (each <tr> element) within the <tbody>). This is not
* cached, so it will be recomputed for each row.
*/
@Parameter(cache = false)
private String _rowClass;
/**
* Object that provides access to the bean and data models used to render the Grid.
*/
@Parameter(value = "componentResources.container")
private GridModelProvider _provider;
/**
* Number of rows displayed on each page. Long result sets are split across multiple pages.
*/
@Parameter(required = true)
private int _rowsPerPage;
/**
* The current page number within the available pages (indexed from 1).
*/
@Parameter(required = true)
private int _currentPage;
/**
* The current row being rendered, this is primarily an output parameter used to allow the Grid, and the Grid's
* container, to know what object is being rendered.
*/
@Parameter(required = true)
private Object _row;
/**
* If true, then the CSS class on each <TD> cell will be omitted, which can reduce the amount of output from
* the component overall by a considerable amount. Leave this as false, the default, when you are leveraging the CSS
* to customize the look and feel of particular columns.
*/
@Parameter
private boolean _lean;
/**
* If true and the Loop is enclosed by a Form, then the normal state saving logic is turned off. Defaults to false,
* enabling state saving logic within Forms.
*/
@SuppressWarnings("unused")
@Parameter
private boolean _volatile;
@Environmental(false)
private FormSupport _formSupport;
private boolean _recordingStateInsideForm;
private int _endRow;
private int _rowIndex;
private String _propertyName;
private PropertyModel _columnModel;
public String getRowClass()
{
List<String> classes = CollectionFactory.newList();
// Not a cached parameter, so careful to only access it once.
String rc = _rowClass;
if (rc != null) classes.add(rc);
if (_rowIndex == _startRow) classes.add(GridConstants.FIRST_CLASS);
if (_rowIndex == _endRow) classes.add(GridConstants.LAST_CLASS);
return TapestryInternalUtils.toClassAttributeValue(classes);
}
public String getCellClass()
{
List<String> classes = CollectionFactory.newList();
if (!_lean)
{
String id = _provider.getDataModel().get(_propertyName).getId();
classes.add(id + "-cell");
}
if (_columnModel.getId().equals(_sortColumnId))
{
String sortClassName = _sortAscending ? GridConstants.SORT_ASCENDING_CLASS : GridConstants.SORT_DESCENDING_CLASS;
classes.add(sortClassName);
}
return TapestryInternalUtils.toClassAttributeValue(classes);
}
void setupRender()
{
GridDataSource dataSource = _provider.getDataSource();
int availableRows = dataSource.getAvailableRows();
int maxPages = ((availableRows - 1) / _rowsPerPage) + 1;
// This can sometimes happen when the number of items shifts between requests.
if (_currentPage > maxPages) _currentPage = maxPages;
_startRow = (_currentPage - 1) * _rowsPerPage;
_endRow = Math.min(availableRows - 1, _startRow + _rowsPerPage - 1);
_rowIndex = _startRow;
_recordingStateInsideForm = !_volatile && _formSupport != null;
}
/**
* Callback method, used when recording state to a form, or called directly when not recording state.
*/
void setupForRow(int rowIndex)
{
_row = _provider.getDataSource().getRowValue(rowIndex);
}
void beginRender()
{
// When needed, store a callback used when the form is submitted.
if (_recordingStateInsideForm) _formSupport.store(this, new SetupForRow(_rowIndex));
// And do it now for the render.
setupForRow(_rowIndex);
}
boolean afterRender()
{
_rowIndex++;
return _rowIndex > _endRow;
}
public List<String> getPropertyNames()
{
return _provider.getDataModel().getPropertyNames();
}
public String getPropertyName()
{
return _propertyName;
}
public void setPropertyName(String propertyName)
{
_propertyName = propertyName;
_columnModel = _provider.getDataModel().get(propertyName);
}
public Object getRow()
{
return _row;
}
public PropertyModel getColumnModel()
{
return _columnModel;
}
}