java 代码
package org.qiwen.pages;
import java.util.Map;
import org.apache.tapestry.Block;
import org.apache.tapestry.annotations.Inject;
import org.apache.tapestry.annotations.Persist;
import org.apache.tapestry.annotations.Retain;
import org.apache.tapestry.ioc.internal.util.CollectionFactory;
public class BlockDemo
{
@Inject
private Block _fred;
@Inject
private Block _barney;
// Blocks not injected until page load, so must lazily initialize the map.
@Retain
private Map _blocks = null;
@Persist
private String _blockName;
public Block getBlockToRender()
{
if (_blocks == null)
{
_blocks = CollectionFactory.newMap();
_blocks.put("fred", _fred);
_blocks.put("barney", _barney);
}
return _blocks.get(_blockName);
}
public String getBlockName()
{
return _blockName;
}
public void setBlockName(String blockName)
{
_blockName = blockName;
}
}
Html 代码
<html xmlns:t="http://tapestry.apache.org/schema/tapestry_5_0_0.xsd">
<form t:type="Form">
<select t:type="Select" t:id="blockName" model="',fred,barney'" onchange="this.form.submit();"/>
<label t:type="Label" for="blockName">Block to display</label>
</form>
<p>The block: ${blockToRender}</p>
</html>
