org.apache.struts2.components.ComboBox Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.struts2.components;
import com.opensymphony.xwork2.util.ValueStack;
import org.apache.struts2.util.MakeIterator;
import org.apache.struts2.views.annotations.StrutsTag;
import org.apache.struts2.views.annotations.StrutsTagAttribute;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
/**
*
*
* The combo box is basically an HTML INPUT of type text and HTML SELECT grouped together to give you a combo box
* functionality. You can place text in the INPUT control by using the SELECT control or type it in directly in
* the text field.
*
*
*
* In this example, the SELECT will be populated from id=year attribute. Counter is itself an Iterator. It will
* span from first to last. The population is done via javascript, and requires that this tag be surrounded by a
* <form>.
*
*
*
* Note that unlike the <s:select/> tag, there is no ability to define the individual <option> tags' id attribute
* or content separately. Each of these is simply populated from the toString() method of the list item. Presumably
* this is because the select box isn't intended to actually submit useful data, but to assist the user in filling
* out the text field.
*
*
*
* Examples
*
*
*
* JSP:
* <-- Example One -->
* <s:bean name="struts.util.Counter" var="year">
* <s:param name="first" value="text('firstBirthYear')"/>
* <s:param name="last" value="2000"/>
*
* <s:combobox label="Birth year" size="6" maxlength="4" name="birthYear" list="#year"/>
* </s:bean>
*
* <-- Example Two -->
* <s:combobox
* label="My Favourite Fruit"
* name="myFavouriteFruit"
* list="{'apple','banana','grape','pear'}"
* headerKey="-1"
* headerValue="--- Please Select ---"
* emptyOption="true"
* value="banana" />
*
* <-- Example Two -->
* <s:combobox
* label="My Favourite Color"
* name="myFavouriteColor"
* list="#{'red':'red','green':'green','blue':'blue'}"
* headerKey="-1"
* headerValue="--- Please Select ---"
* emptyOption="true"
* value="green" />
*
* Velocity:
* #tag( ComboBox "label=Birth year" "size=6" "maxlength=4" "name=birthYear" "list=#year" )
*
*
*
*/
@StrutsTag(name="combobox", tldTagClass="org.apache.struts2.views.jsp.ui.ComboBoxTag", description="Widget that fills a text box from a select")
public class ComboBox extends TextField {
final public static String TEMPLATE = "combobox";
protected String list;
protected String listKey;
protected String listValue;
protected String headerKey;
protected String headerValue;
protected String emptyOption;
public ComboBox(ValueStack stack, HttpServletRequest request, HttpServletResponse response) {
super(stack, request, response);
}
protected String getDefaultTemplate() {
return TEMPLATE;
}
public void evaluateExtraParams() {
super.evaluateExtraParams();
Object value = findListValue();
if (headerKey != null) {
addParameter("headerKey", findString(headerKey));
}
if (headerValue != null) {
addParameter("headerValue", findString(headerValue));
}
if (emptyOption != null) {
addParameter("emptyOption", findValue(emptyOption, Boolean.class));
}
if (value != null) {
if (value instanceof Collection) {
Collection tmp = (Collection) value;
addParameter("list", tmp);
if (listKey != null) {
addParameter("listKey", listKey);
}
if (listValue != null) {
addParameter("listValue", listValue);
}
} else if (value instanceof Map) {
Map tmp = (Map) value;
addParameter("list", MakeIterator.convert(tmp));
addParameter("listKey", "key");
addParameter("listValue", "value");
} else { // also covers "if (value.getClass().isArray())"
Iterator i = MakeIterator.convert(value);
addParameter("list", i);
if (listKey != null) {
addParameter("listKey", listKey);
}
if (listValue != null) {
addParameter("listValue", listValue);
}
}
}
}
protected Object findListValue() {
return findValue(list, "list",
"You must specify a collection/array/map/enumeration/iterator. " +
"Example: people or people.{name}");
}
@StrutsTagAttribute(description = "Iterable source to populate from. " +
"If this is missing, the select widget is simply not displayed.", required=true)
public void setList(String list) {
this.list = list;
}
@StrutsTagAttribute(description="Decide if an empty option is to be inserted. Default false.")
public void setEmptyOption(String emptyOption) {
this.emptyOption = emptyOption;
}
@StrutsTagAttribute(description="Set the header key for the header option.")
public void setHeaderKey(String headerKey) {
this.headerKey = headerKey;
}
@StrutsTagAttribute(description="Set the header value for the header option.")
public void setHeaderValue(String headerValue) {
this.headerValue = headerValue;
}
@StrutsTagAttribute(description = "Set the key used to retrieve the option key.")
public void setListKey(String listKey) {
this.listKey = listKey;
}
@StrutsTagAttribute(description = "Set the value used to retrieve the option value.")
public void setListValue(String listValue) {
this.listValue = listValue;
}
}