## Class TImageButton

Description

Implements interfaces:

- IPostBackDataHandler
- IPostBackEventHandler
- IButtonControl

TImageButton class

TImageButton creates an image button on the page. It is used to submit data to a page. You can create either a submit button or a command button.

A command button has a command name (specified by the CommandName property) and and a command parameter (specified by CommandParameter property) associated with the button. This allows you to create multiple TLinkButton components on a Web page and programmatically determine which one is clicked with what parameter. You can provide an event handler for OnCommand event to programmatically control the actions performed when the command button is clicked. In the event handler, you can determine the CommandName property value and the CommandParameter property value through the TCommandParameter::getName and TCommandParameter::getParameter properties of the event parameter which is of type TCommandEventParameter.

A submit button does not have a command name associated with the button and clicking on it simply posts the Web page back to the server. By default, a TImageButton control is a submit button. You can provide an event handler for the OnClick event to programmatically control the actions performed when the submit button is clicked. The coordinates of the clicking point can be obtained from the OnClick event parameter, which is of type TImageClickEventParameter.

Clicking on button can trigger form validation, if CausesValidation is true. And the validation may be restricted within a certain group of validator controls by setting ValidationGroup property. If validation is successful, the data will be post back to the same page.

TImageButton displays the Text property as the hint text to the displayed image.

- since: 3.0
- version: $Revision: $ $Date: $
- author: Qiang Xue <qiang.xue@gmail.com>

Located in /Web/UI/WebControls/TImageButton.php (line 59)

    TComponent
       |
       --TApplicationComponent
          |
          --TControl
             |
             --TWebControl
                |
                --TImage
                   |
                   --TImageButton

Method Summary
void addAttributesToRender (THtmlWriter $writer)
boolean canCauseValidation ()
boolean getCausesValidation ()
string getCommandName ()
string getCommandParameter ()
array getPostBackOptions ()
string getTagName ()
string getText ()
string getValidationGroup ()
boolean loadPostData (string $key, array $values)
void onClick (TImageClickEventParameter $param)
void onCommand (TCommandEventParameter $param)
void onPreRender (mixed $param)
void raisePostBackEvent (TEventParameter $param)
void raisePostDataChangedEvent ()
void renderContents (THtmlWriter $writer)
void setCausesValidation (boolean $value)
void setCommandName (string $value)
void setCommandParameter (string $value)
void setText (string $value)
void setValidationGroup (string $value)
Methods
addAttributesToRender (line 83)

Adds attribute name-value pairs to renderer.

This overrides the parent implementation with additional button specific attributes.

- access: protected

void addAttributesToRender (THtmlWriter $writer)

- THtmlWriter $writer: the writer used for the rendering purpose

Redefinition of:

TImage::addAttributesToRender()
  Adds attributes related to an HTML image element to renderer.

canCauseValidation (line 106)

- return: whether to perform validation if the button is clicked
- access: protected

boolean canCauseValidation ()
getCausesValidation (line 204)

- return: whether postback event trigger by this button will cause input validation, default is true
- access: public

boolean getCausesValidation ()
getCommandName (line 220)

- return: the command name associated with the OnCommand event.
- access: public

string getCommandName ()
getCommandParameter (line 236)

- return: the parameter associated with the OnCommand event
- access: public

string getCommandParameter ()
getPostBackOptions (line 122)

Returns postback specifications for the button.

This method is used by framework and control developers.

- return: parameters about how the button defines its postback behavior.
- access: protected

array getPostBackOptions ()
getTagName (line 73)

- return: tag name of the button
- access: protected

string getTagName ()

Redefinition of:

TImage::getTagName()

getText (line 268)

- return: caption of the button
- access: public

string getText ()
getValidationGroup (line 252)

- return: the group of validators which the button causes validation upon postback
- access: public

string getValidationGroup ()
loadPostData (line 139)

This method checks if the TImageButton is clicked and loads the coordinates of the clicking position.

This method is primarly used by framework developers.

- return: whether the data of the component has been changed
- access: public

boolean loadPostData (string $key, array $values)

- string $key: the key that can be used to retrieve data from the input data collection
- array $values: the input data collection

onClick (line 166)

This method is invoked when the button is clicked.

The method raises 'OnClick' event to fire up the event handlers. If you override this method, be sure to call the parent implementation so that the event handler can be invoked.

- access: public

void onClick (TImageClickEventParameter $param)

- TImageClickEventParameter $param: event parameter to be passed to the event handlers

onCommand (line 178)

This method is invoked when the button is clicked.

The method raises 'OnCommand' event to fire up the event handlers. If you override this method, be sure to call the parent implementation so that the event handlers can be invoked.

- access: public

void onCommand (TCommandEventParameter $param)

- TCommandEventParameter $param: event parameter to be passed to the event handlers

onPreRender (line 288)

Registers the image button to receive postback data during postback.

This is necessary because an image button, when postback, does not have direct mapping between post data and the image button name. This method overrides the parent implementation and is invoked before render.

- access: public

void onPreRender (mixed $param)

- mixed $param: event parameter

Redefinition of:

TControl::onPreRender()
  This method is invoked when the control enters 'OnPreRender' stage.

raisePostBackEvent (line 193)

Raises the postback event.

This method is required by IPostBackEventHandler interface. If CausesValidation is true, it will invoke the page's TPage::validate method first. It will raise OnClick and OnCommand events. This method is mainly used by framework and control developers.

- access: public

void raisePostBackEvent (TEventParameter $param)

- TEventParameter $param: the event parameter

raisePostDataChangedEvent (line 154)

A dummy implementation for the IPostBackDataHandler interface.

- access: public

void raisePostDataChangedEvent ()
renderContents (line 299)

Renders the body content enclosed between the control tag.

This overrides the parent implementation with nothing to be rendered.

- access: public

void renderContents (THtmlWriter $writer)

- THtmlWriter $writer: the writer used for the rendering purpose

Redefinition of:

TImage::renderContents()
  Renders the body content of the image.

setCausesValidation (line 212)

- access: public

void setCausesValidation (boolean $value)

- boolean $value: whether postback event trigger by this button will cause input validation

setCommandName (line 228)

- access: public

void setCommandName (string $value)

- string $value: the command name associated with the OnCommand event.

setCommandParameter (line 244)

- access: public

void setCommandParameter (string $value)

- string $value: the parameter associated with the OnCommand event.

setText (line 276)

- access: public

void setText (string $value)

- string $value: caption of the button

setValidationGroup (line 260)

- access: public

void setValidationGroup (string $value)

- string $value: the group of validators which the button causes validation upon postback

#### Inherited Methods

Inherited From TImage

> TImage::addAttributesToRender()
> TImage::getAlternateText()
> TImage::getDescriptionUrl()
> TImage::getImageAlign()
> TImage::getImageUrl()
> TImage::getTagName()
> TImage::renderContents()
> TImage::setAlternateText()
> TImage::setDescriptionUrl()
> TImage::setImageAlign()
> TImage::setImageUrl()

Inherited From TWebControl

> TWebControl::addAttributesToRender()
> TWebControl::copyBaseAttributes()
> TWebControl::createStyle()
> TWebControl::getAccessKey()
> TWebControl::getBackColor()
> TWebControl::getBorderColor()
> TWebControl::getBorderStyle()
> TWebControl::getBorderWidth()
> TWebControl::getCssClass()
> TWebControl::getFont()
> TWebControl::getForeColor()
> TWebControl::getHasStyle()
> TWebControl::getHeight()
> TWebControl::getStyle()
> TWebControl::getTabIndex()
> TWebControl::getTagName()
> TWebControl::getToolTip()
> TWebControl::getWidth()
> TWebControl::render()
> TWebControl::renderBeginTag()
> TWebControl::renderContents()
> TWebControl::renderEndTag()
> TWebControl::setAccessKey()
> TWebControl::setBackColor()
> TWebControl::setBorderColor()
> TWebControl::setBorderStyle()
> TWebControl::setBorderWidth()
> TWebControl::setCssClass()
> TWebControl::setForeColor()
> TWebControl::setHeight()
> TWebControl::setStyle()
> TWebControl::setTabIndex()
> TWebControl::setToolTip()
> TWebControl::setWidth()

Inherited From TControl

> TControl::__construct()
> TControl::addedControl()
> TControl::addParsedObject()
> TControl::applyStyleSheetSkin()
> TControl::autoBindProperty()
> TControl::autoDataBindProperties()
> TControl::bindProperty()
> TControl::broadcastEvent()
> TControl::broadcastEventInternal()
> TControl::clearChildState()
> TControl::clearControlState()
> TControl::clearNamingContainer()
> TControl::clearViewState()
> TControl::createChildControls()
> TControl::createControlCollection()
> TControl::createdOnTemplate()
> TControl::dataBind()
> TControl::dataBindChildren()
> TControl::dataBindProperties()
> TControl::ensureChildControls()
> TControl::findControl()
> TControl::findControlsByID()
> TControl::findControlsByType()
> TControl::focus()
> TControl::getAdapter()
> TControl::getAllowChildControls()
> TControl::getAttribute()
> TControl::getAttributes()
> TControl::getChildControlsCreated()
> TControl::getClientID()
> TControl::getControls()
> TControl::getControlStage()
> TControl::getControlState()
> TControl::getEnabled()
> TControl::getEnableTheming()
> TControl::getEnableViewState()
> TControl::getHasAdapter()
> TControl::getHasAttributes()
> TControl::getHasControls()
> TControl::getID()
> TControl::getNamingContainer()
> TControl::getPage()
> TControl::getParent()
> TControl::getRegisteredObject()
> TControl::getSkinID()
> TControl::getSourceTemplateControl()
> TControl::getTemplateControl()
> TControl::getUniqueID()
> TControl::getViewState()
> TControl::getVisible()
> TControl::hasAttribute()
> TControl::initRecursive()
> TControl::isDescendentOf()
> TControl::isObjectRegistered()
> TControl::loadRecursive()
> TControl::loadState()
> TControl::loadStateRecursive()
> TControl::onBubbleEvent()
> TControl::onDataBinding()
> TControl::onInit()
> TControl::onLoad()
> TControl::onPreRender()
> TControl::onUnload()
> TControl::preRenderRecursive()
> TControl::raiseBubbleEvent()
> TControl::registerObject()
> TControl::removeAttribute()
> TControl::removedControl()
> TControl::render()
> TControl::renderChildren()
> TControl::renderControl()
> TControl::saveState()
> TControl::saveStateRecursive()
> TControl::setAdapter()
> TControl::setAttribute()
> TControl::setChildControlsCreated()
> TControl::setControlStage()
> TControl::setControlState()
> TControl::setEnabled()
> TControl::setEnableTheming()
> TControl::setEnableViewState()
> TControl::setID()
> TControl::setPage()
> TControl::setSkinID()
> TControl::setTemplateControl()
> TControl::setViewState()
> TControl::setVisible()
> TControl::traverseChildControls()
> TControl::unbindProperty()
> TControl::unloadRecursive()
> TControl::unregisterObject()
> TControl::__get()

Inherited From TApplicationComponent

> TApplicationComponent::getApplication()
> TApplicationComponent::getRequest()
> TApplicationComponent::getResponse()
> TApplicationComponent::getService()
> TApplicationComponent::getSession()
> TApplicationComponent::getUser()
> TApplicationComponent::publishAsset()
> TApplicationComponent::publishFilePath()

Inherited From TComponent

> TComponent::attachEventHandler()
> TComponent::canGetProperty()
> TComponent::canSetProperty()
> TComponent::detachEventHandler()
> TComponent::evaluateExpression()
> TComponent::evaluateStatements()
> TComponent::getEventHandlers()
> TComponent::getSubProperty()
> TComponent::hasEvent()
> TComponent::hasEventHandler()
> TComponent::hasProperty()
> TComponent::raiseEvent()
> TComponent::setSubProperty()
> TComponent::__get()
> TComponent::__set()

Class Constants

#### Inherited Constants

Inherited from TControl

Documentation generated on Mon, 01 May 2006 23:03:47 -0400 by phpDocumentor 1.3.0RC4