// Copyright 2004, 2005 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.contrib.table.components;
import java.util.Iterator;
import org.apache.tapestry.IAsset;
import org.apache.tapestry.IMarkupWriter;
import org.apache.tapestry.IRender;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.contrib.table.model.ITableColumn;
import org.apache.tapestry.contrib.table.model.ITableColumnModel;
/**
* A low level Table component that renders the column headers in the table. This component must be
* wrapped by {@link org.apache.tapestry.contrib.table.components.TableView}.
* <p>
* The component iterates over all column objects in the
* {@link org.apache.tapestry.contrib.table.model.ITableColumnModel}and renders a header for each
* one of them using the renderer provided by the getColumnRender() method in
* {@link org.apache.tapestry.contrib.table.model.ITableColumn}. The headers are wrapped in 'th'
* tags by default.
* <p>
* Please see the Component Reference for details on how to use this component. [ <a
* href="../../../../../../../ComponentReference/contrib.TableColumns.html">Component Reference
* </a>]
*
* @author mindbridge
*/
public abstract class TableColumns extends AbstractTableViewComponent
{
public static final String TABLE_COLUMN_ARROW_UP_ATTRIBUTE = "org.apache.tapestry.contrib.table.components.TableColumns.arrowUp";
public static final String TABLE_COLUMN_ARROW_DOWN_ATTRIBUTE = "org.apache.tapestry.contrib.table.components.TableColumns.arrowDown";
public static final String TABLE_COLUMN_CSS_CLASS_SUFFIX = "ColumnHeader";
public abstract IAsset getArrowDownAsset();
public abstract IAsset getArrowUpAsset();
public abstract void setColumn(ITableColumn column);
// Transient
private ITableColumn m_objTableColumn = null;
/**
* Returns the currently rendered table column. You can call this method to obtain the current
* column.
*
* @return ITableColumn the current table column
*/
public ITableColumn getTableColumn()
{
return m_objTableColumn;
}
/**
* Sets the currently rendered table column. This method is for internal use only.
*
* @param tableColumn
* The current table column
*/
public void setTableColumn(ITableColumn tableColumn)
{
m_objTableColumn = tableColumn;
if (isParameterBound("column"))
setColumn(tableColumn);
}
/**
* Get the list of all table columns to be displayed.
*
* @return an iterator of all table columns
*/
public Iterator getTableColumnIterator()
{
ITableColumnModel objColumnModel = getTableModelSource().getTableModel().getColumnModel();
return objColumnModel.getColumns();
}
/**
* Returns the renderer to be used to generate the header of the current column
*
* @return the header renderer of the current column
*/
public IRender getTableColumnRenderer()
{
return getTableColumn().getColumnRenderer(
getPage().getRequestCycle(),
getTableModelSource());
}
public abstract String getColumnClassParameter();
/**
* Returns the CSS class of the generated table cell. It uses the class parameter if it has been
* bound, or the default value of "[column name]ColumnHeader" otherwise.
*
* @return the CSS class of the cell
*/
public String getColumnClass()
{
if (isParameterBound("class"))
return getColumnClassParameter();
return getTableColumn().getColumnName() + TABLE_COLUMN_CSS_CLASS_SUFFIX;
}
/**
* @see org.apache.tapestry.BaseComponent#renderComponent(IMarkupWriter, IRequestCycle)
*/
protected void renderComponent(IMarkupWriter writer, IRequestCycle cycle)
{
Object oldValueUp = cycle.getAttribute(TABLE_COLUMN_ARROW_UP_ATTRIBUTE);
Object oldValueDown = cycle.getAttribute(TABLE_COLUMN_ARROW_DOWN_ATTRIBUTE);
try
{
cycle.setAttribute(TABLE_COLUMN_ARROW_UP_ATTRIBUTE, getArrowUpAsset());
cycle.setAttribute(TABLE_COLUMN_ARROW_DOWN_ATTRIBUTE, getArrowDownAsset());
super.renderComponent(writer, cycle);
}
finally
{
cycle.setAttribute(TABLE_COLUMN_ARROW_UP_ATTRIBUTE, oldValueUp);
cycle.setAttribute(TABLE_COLUMN_ARROW_DOWN_ATTRIBUTE, oldValueDown);
// set the current column to null when the component is not active
m_objTableColumn = null;
}
}
}