com.google.gwt.user.client.ui.Hidden Maven / Gradle / Ivy
/*
* Copyright 2008 Google Inc.
*
* 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 com.google.gwt.user.client.ui;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.InputElement;
import com.google.gwt.editor.client.IsEditor;
import com.google.gwt.editor.client.LeafValueEditor;
import com.google.gwt.editor.client.adapters.TakesValueEditor;
import com.google.gwt.user.client.TakesValue;
/**
* Represents a hidden field in an HTML form.
*/
public class Hidden extends Widget implements HasName, TakesValue, IsEditor> {
/**
* Creates a Hidden widget that wraps an existing <input type='hidden'>
* element.
*
* This element must already be attached to the document. If the element is
* removed from the document, you must call
* {@link RootPanel#detachNow(Widget)}.
*
* @param element the element to be wrapped
*/
public static Hidden wrap(Element element) {
// Assert that the element is attached.
assert Document.get().getBody().isOrHasChild(element);
Hidden hidden = new Hidden(element);
// Mark it attached and remember it for cleanup.
hidden.onAttach();
RootPanel.detachOnWindowClose(hidden);
return hidden;
}
private LeafValueEditor editor;
/**
* Constructor for Hidden.
*/
public Hidden() {
setElement(Document.get().createHiddenInputElement());
}
/**
* Constructor for Hidden.
*
* @param name name of the hidden field
*/
public Hidden(String name) {
this();
setName(name);
}
/**
* Constructor for Hidden.
*
* @param name name of the hidden field
* @param value value of the hidden field
*/
public Hidden(String name, String value) {
this(name);
setValue(value);
}
/**
* This constructor may be used by subclasses to explicitly use an existing
* element. This element must be an <input> element whose type is
* 'hidden'.
*
* @param element the element to be used
*/
protected Hidden(Element element) {
assert InputElement.as(element).getType().equalsIgnoreCase("hidden");
setElement(element);
}
public LeafValueEditor asEditor() {
if (editor == null) {
editor = TakesValueEditor.of(this);
}
return editor;
}
/**
* Gets the default value of the hidden field.
*
* @return the default value
*/
public String getDefaultValue() {
return getInputElement().getDefaultValue();
}
/**
* Gets the id of the hidden field.
*
* @return the id
*/
public String getID() {
return getElement().getId();
}
/**
* Gets the name of the hidden field.
*
* @return the name
*/
public String getName() {
return getInputElement().getName();
}
/**
* Gets the value of the hidden field.
*
* @return the value
*/
public String getValue() {
return getInputElement().getValue();
}
/**
* Sets the default value of the hidden field.
*
* @param defaultValue default value to set
*/
public void setDefaultValue(String defaultValue) {
getInputElement().setDefaultValue(defaultValue);
}
/**
* Sets the id of the hidden field.
*
* @param id id to set
*/
public void setID(String id) {
getElement().setId(id);
}
/**
* Sets the name of the hidden field.
*
* @param name name of the field
*/
public void setName(String name) {
if (name == null) {
throw new NullPointerException("Name cannot be null");
} else if (name.equals("")) {
throw new IllegalArgumentException("Name cannot be an empty string.");
}
getInputElement().setName(name);
}
/**
* Sets the value of the hidden field.
*
* @param value value to set
*/
public void setValue(String value) {
getInputElement().setValue(value);
}
private InputElement getInputElement() {
return getElement().cast();
}
}