net.sf.click.control
Class HiddenField

java.lang.Object
  net.sf.click.control.AbstractControl
      net.sf.click.control.Field
          net.sf.click.control.HiddenField

All Implemented Interfaces:

Control, Serializable

public class HiddenField

extends Field

Provides a Hidden Field control: <input type='hidden'>.

The HiddenField control is useful for storing state information in a Form, such as object ids, instead of using the Session object. This control is capable of supporting the following classes:

• Boolean
• Date
• Double
• Float
• Integer
• Long
• Short
• String
• Serializable

Serializable non-primitive objects will be serialized, compressed and Base64 encoded, using ClickUtils.encode(Object) method, and decoded using the corresponding ClickUtils.decode(String) method.

HiddenField Example

An example is provided below which uses a hidden field to count the number of times a form is consecutively submitted. The count is displayed in the page template using the model "count" value.

 public class CountPage extends Page {

     public Form form = new Form();
     public Integer count;

     private HiddenField counterField = new HiddenField("counterField", Integer.class);

     public CountPage() {
         form.add(counterField);
         form.add(new Submit("ok", "  OK  "));
     }

     public void onGet() {
         count = new Integer(0);
         counterField.setValueObject(count);
     }

     public void onPost() {
         count = (Integer) counterField.getValueObject();
         count = new Integer(count.intValue() + 1);
         counterField.setValueObject(count);
     }
 } 

See also W3C HTML reference INPUT

Author:

Malcolm Edgar

See Also:

Serialized Form

Field Summary

protected Class	valueClass The field value Class.
protected Object	valueObject The field value Object.

Fields inherited from class net.sf.click.control.Field

disabled, error, focus, form, help, label, readonly, required, tabindex, title, validate, value

Fields inherited from class net.sf.click.control.AbstractControl

actionListener, attributes, listener, listenerMethod, messages, name, parent, styles

Fields inherited from interface net.sf.click.Control

CONTROL_MESSAGES

Constructor Summary

HiddenField()
Create an HiddenField with no name or Class defined.

HiddenField(String name, Class valueClass)
Construct a HiddenField with the given name and Class.

HiddenField(String name, Object value)
Construct a HiddenField with the given name and value object.

Method Summary

void	bindRequestValue() This method binds the submitted request value to the Field's value.
String	getTag() Return the hiddenfield's html tag: input.
String	getType() Return the input type: 'hidden'.
String	getValidationJavaScript() Returns null to ensure no client side JavaScript validation is performed.
String	getValue() Return the Field value.
Class	getValueClass() Return the registered Class for the Hidden Field value Object.
Object	getValueObject() Return the value Object of the hidden field.
boolean	isHidden() Returns true.
void	render(HtmlStringBuffer buffer) Render the HTML representation of the HiddenField.
void	setValue(String value) Set the Field value.
void	setValueClass(Class valueClass) Set the registered Class for the Hidden Field value Object.
void	setValueObject(Object value) Set the value of the field using the given object.

Methods inherited from class net.sf.click.control.Field

getError, getErrorLabel, getFocus, getFocusJavaScript, getForm, getHelp, getId, getLabel, getRequestValue, getTabIndex, getTextAlign, getTitle, getValidate, getWidth, isDisabled, isReadonly, isRequired, isValid, onInit, onProcess, setDisabled, setError, setErrorMessage, setErrorMessage, setErrorMessage, setErrorMessage, setFocus, setForm, setHelp, setLabel, setListener, setParent, setReadonly, setRequired, setTabIndex, setTextAlign, setTitle, setValidate, setWidth, validate

Methods inherited from class net.sf.click.control.AbstractControl

addStyleClass, appendAttributes, getActionListener, getAttribute, getAttributes, getContext, getControlSizeEst, getHtmlImports, getMessage, getMessage, getMessage, getMessages, getName, getPage, getParent, getStyle, getStyles, hasAttribute, hasAttributes, hasStyles, onDeploy, onDestroy, onRender, registerActionEvent, removeStyleClass, renderTagBegin, renderTagEnd, setActionListener, setAttribute, setId, setName, setStyle, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

valueObject

protected Object valueObject

The field value Object.

valueClass

protected Class valueClass

The field value Class.

Constructor Detail

HiddenField

public HiddenField(String name,
                   Class valueClass)

Construct a HiddenField with the given name and Class.

Parameters:

name - the name of the hidden field

valueClass - the Class of the value Object

HiddenField

public HiddenField(String name,
                   Object value)

Construct a HiddenField with the given name and value object.

Parameters:

name - the name of the hidden field

value - the value object

HiddenField

public HiddenField()

Create an HiddenField with no name or Class defined. Please note the HiddenField's name and value Class must be defined before it is valid.

Method Detail

getTag

public String getTag()

Return the hiddenfield's html tag: input.

Overrides:

getTag in class AbstractControl

Returns:

this controls html tag

See Also:

AbstractControl.getTag()

isHidden

public boolean isHidden()

Returns true.

Overrides:

isHidden in class Field

Returns:

true

See Also:

Field.isHidden()

getType

public String getType()

Return the input type: 'hidden'.

Returns:

the input type: 'hidden'

getValue

public String getValue()

Description copied from class: Field

Return the Field value.

Overrides:

getValue in class Field

Returns:

the Field value

See Also:

Field.getValue()

setValue

public void setValue(String value)

Description copied from class: Field

Set the Field value.

Overrides:

setValue in class Field

Parameters:

value - the Field value

See Also:

Field.setValue(String)

getValueClass

public Class getValueClass()

Return the registered Class for the Hidden Field value Object.

Returns:

the registered Class for the Hidden Field value Object

setValueClass

public void setValueClass(Class valueClass)

Set the registered Class for the Hidden Field value Object.

Parameters:

valueClass - the registered Class for the Hidden Field value Object

getValueObject

public Object getValueObject()

Return the value Object of the hidden field.

Overrides:

getValueObject in class Field

Returns:

the object representation of the Field value

See Also:

Field.getValueObject()

setValueObject

public void setValueObject(Object value)

Description copied from class: Field

Set the value of the field using the given object.

Overrides:

setValueObject in class Field

Parameters:

value - the object value to set

See Also:

Field.setValueObject(Object)

getValidationJavaScript

public String getValidationJavaScript()

Returns null to ensure no client side JavaScript validation is performed.

Overrides:

getValidationJavaScript in class Field

Returns:

null to ensure no client side JavaScript validation is performed

bindRequestValue

public void bindRequestValue()

This method binds the submitted request value to the Field's value.

Overrides:

bindRequestValue in class Field

render

public void render(HtmlStringBuffer buffer)

Render the HTML representation of the HiddenField.

Specified by:

render in interface Control

Overrides:

render in class AbstractControl

Parameters:

buffer - the specified buffer to render the control's output to

See Also:

Control.render(net.sf.click.util.HtmlStringBuffer)