第四十三讲：tapestry Ajax表单验证
tapestry Ajax表单验证，作用非常大可做检查用户名是否存在。源码如下：
AJAXValidators1.java
/**
* 项目名称：TapestryStart
* 开发模式：Maven+Tapestry5.x+Tapestry-hibernate+Mysql
* 网址： http://www.flywind.org
* 版本：1.0
* 编写：飞风
* 时间：2012-02-29
*/
package com.tapestry.app.pages;
import java.util.List;
import org.apache.tapestry5.annotations.InjectPage;
import org.apache.tapestry5.annotations.Property;
import org.apache.tapestry5.ioc.annotations.Inject;
import org.apache.tapestry5.json.JSONObject;
import org.apache.tapestry5.services.Request;
import com.tapestry.app.entities.Person;
import com.tapestry.app.services.StartDAO;
public class AJAXValidators1 {
@Property
private String firstName;
@Property
private String lastName;
@Property
@SuppressWarnings("unused")
private List<Person> persons;
@InjectPage
private AJAXValidators2 page2;
@Inject
private Request request;
@Inject
private StartDAO dao;
void setupRender() {
StringBuffer sql = new StringBuffer();
sql.append("from Person");
persons = dao.findWithQuery(sql.toString());
}
JSONObject onAjaxValidateFromFirstName() {
String firstName = request.getParameter("param");
try {
validateFirstNameIsUnique(firstName);
}
catch (Exception e) {
return new JSONObject().put("error", e.getMessage());
}
return new JSONObject();
}
Object onSuccess() {
page2.set(firstName, lastName);
return page2;
}
void validateFirstNameIsUnique(String firstName) throws Exception {
if (firstName != null) {
List<Person> persons = dao.searchQuery(firstName);
if (persons.size() > 0) {
throw new Exception("姓已经存在.");
}
}
}
}
AJAXValidators1.tml
<html t:type="layout" title="tapestryStart Index" t:sidebarTitle="Framework Version"
xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd" xmlns:p="tapestry:parameter">
<div style="margin: 20px;">
<form t:type="CustomForm" t:id="inputs">
<t:errors/>
<table>
<tr>
<td><t:label for="firstName"/>:</td>
<td><input t:type="TextField" t:id="firstName" t:validate="required, maxlength=10" size="10"
t:mixins="ajaxValidator"/></td>
<td>(required, maxLength=10, new name only)</td>
</tr>
<tr>
<th></th>
<td colspan="2"><t:customerror for="firstName"/></td>
</tr>
<tr>
<td><t:label for="lastName"/>:</td>
<td><input t:type="TextField" t:id="lastName" t:validate="required, maxLength=10" size="10"/></td>
<td>(required, maxLength=10, new name only)</td>
</tr>
<tr>
<th></th>
<td colspan="2"><t:customerror for="lastName"/></td>
</tr>
<tr>
<td></td>
<td><input type="submit" value="Display"/></td>
<td></td>
</tr>
</table>
</form><br/>
<table t:type="grid" t:source="persons" t:row="var:person" include="firstName,lastName">[Grid here]</table>
</div>
</html>
AjaxValidator.java
/**
* 项目名称：TapestryStart
* 开发模式：Maven+Tapestry5.x+Tapestry-hibernate+Mysql
* 网址： http://www.flywind.org
* 版本：1.0
* 编写：飞风
* 时间：2012-02-29
*/
package com.tapestry.app.mixins;
import org.apache.tapestry5.ClientElement;
import org.apache.tapestry5.ComponentResources;
import org.apache.tapestry5.annotations.Import;
import org.apache.tapestry5.annotations.InjectContainer;
import org.apache.tapestry5.ioc.annotations.Inject;
import org.apache.tapestry5.json.JSONObject;
import org.apache.tapestry5.services.javascript.JavaScriptSupport;
@Import(library = "context:assets/js/AjaxValidator.js")
public class AjaxValidator {
@Inject
private ComponentResources componentResources;
@Inject
private JavaScriptSupport javaScriptSupport;
@InjectContainer
private ClientElement clientElement;
void afterRender() {
JSONObject spec = new JSONObject();
spec.put("elementId", clientElement.getClientId());
spec.put("listenerURI", componentResources.createEventLink("ajaxValidate").toAbsoluteURI());
javaScriptSupport.addInitializerCall("ajaxValidator", spec);
}
}
AjaxValidator.js
AjaxValidator = Class.create( {
initialize : function(spec) {
this.field = $(spec.elementId);
this.listenerURI = spec.listenerURI;
// Set up a listener that validates the field - asynchronously in the server - on change of focus
document.observe(Tapestry.FOCUS_CHANGE_EVENT, function(event) {
// If changing focus *within the same form* then perform validation.
// Note that Tapestry.currentFocusField does not change
// until after the FOCUS_CHANGE_EVENT notification.
if (Tapestry.currentFocusField == this.field && this.field.form == event.memo.form) {
this.asyncValidateInServer();
}
}.bindAsEventListener(this)
);
},
asyncValidateInServer : function() {
var value = this.field.value;
var listenerURIWithValue = this.listenerURI;
if (value) {
listenerURIWithValue = addRequestParameter('param', value, this.listenerURI);
new Ajax.Request(listenerURIWithValue, {
method: 'get',
onFailure: function(t) {
alert('Error communication with the server: ' + t.responseText.stripTags());
},
onException: function(t, exception) {
alert('Error communication with the server: ' + exception.message);
},
onSuccess: function(t) {
if (t.responseJSON.error) {
this.field.showValidationMessage(t.responseJSON.error);
}
}.bind(this)
});
}
}
} )
function addRequestParameter(name, value, url) {
if (url.indexOf('?') < 0) {
url += '?'
} else {
url += '&';
}
value = escape(value);
url += name + '=' + value;
return url;
}
// Extend the Tapestry.Initializer with a static method that instantiates an AjaxValidator.
Tapestry.Initializer.ajaxValidator = function(spec) {
new AjaxValidator(spec);
}
AJAXValidators2.java
/**
* 项目名称：TapestryStart
* 开发模式：Maven+Tapestry5.x+Tapestry-hibernate+Mysql
* 网址： http://www.flywind.org
* 版本：1.0
* 编写：飞风
* 时间：2012-02-29
*/
package com.tapestry.app.pages;
public class AJAXValidators2 {
private String firstName;
private String lastName;
public void set(String firstName, String lastName) {
this.firstName = firstName;
this.lastName = lastName;
}
String[] onPassivate() {
return new String[] { firstName, lastName };
}
void onActivate(String firstName, String lastName) {
this.firstName = firstName;
this.lastName = lastName;
}
public String getName() {
return firstName + " " + lastName;
}
}
AJAXValidators2.tml
<html t:type="layout" title="tapestryStart Index" t:sidebarTitle="Framework Version"
xmlns:t="http://tapestry.apache.org/schema/tapestry_5_3.xsd" xmlns:p="tapestry:parameter">
你好， ${name}
</html>