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 {@link setCommandName CommandName} property) and and a command parameter
(specified by {@link setCommandParameter 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
{@link onCommand OnCommand} event to programmatically control the actions performed
when the command button is clicked. In the event handler, you can determine
the {@link setCommandName CommandName} property value and
the {@link setCommandParameter CommandParameter} property value
through the {@link TCommandParameter::getName Name} and
{@link TCommandParameter::getParameter Parameter} properties of the event
parameter which is of type {@link \Prado\Web\UI\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 {@link onClick 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 {@link onClick OnClick}
event parameter, which is of type {@link TImageClickEventParameter}.
Clicking on button can trigger form validation, if
{@link setCausesValidation CausesValidation} is true.
And the validation may be restricted within a certain group of validator
controls by setting {@link setValidationGroup ValidationGroup} property.
If validation is successful, the data will be post back to the same page.
TImageButton displays the {@link setText Text} property as the hint text to the displayed image.
/**
* Creates a navigation button.
* It creates a {@link TButton}, {@link TLinkButton}, or {@link TImageButton},
* depending on the given parameters.
* @param TWizardNavigationButtonStyle button style
* @param boolean whether the button should cause validation
* @param string command name for the button's OnCommand event
* @throws TInvalidDataValueException if the button type is not recognized
*/
protected function createNavigationButton($buttonStyle, $causesValidation, $commandName)
{
switch ($buttonStyle->getButtonType()) {
case TWizardNavigationButtonType::Button:
$button = new TButton();
break;
case TWizardNavigationButtonType::Link:
$button = new TLinkButton();
break;
case TWizardNavigationButtonType::Image:
$button = new TImageButton();
$button->setImageUrl($buttonStyle->getImageUrl());
break;
default:
throw new TInvalidDataValueException('wizard_buttontype_unknown', $buttonStyle->getButtonType());
}
$button->setText($buttonStyle->getButtonText());
$button->setCausesValidation($causesValidation);
$button->setCommandName($commandName);
return $button;
}
/**
* Creates a pager button.
* Depending on the button type, a TLinkButton or a TButton may be created.
* If it is enabled (clickable), its command name and parameter will also be set.
* Derived classes may override this method to create additional types of buttons, such as TImageButton.
* @param string button type, either LinkButton or PushButton
* @param boolean whether the button should be enabled
* @param string caption of the button.
* @param string CommandName corresponding to the OnCommand event of the button.
* @param string CommandParameter corresponding to the OnCommand event of the button
* @return mixed the button instance
*/
protected function createPagerButton($buttonType, $enabled, $text, $commandName, $commandParameter)
{
if ($buttonType === TPagerButtonType::LinkButton) {
if ($enabled) {
$button = new TLinkButton();
} else {
$button = new TLabel();
$button->setText($text);
$button->setCssClass($this->getButtonCssClass());
return $button;
}
} else {
if ($buttonType === TPagerButtonType::ImageButton) {
$button = new TImageButton();
$button->setImageUrl($this->getPageImageUrl($text, $commandName));
} else {
$button = new TButton();
}
if (!$enabled) {
$button->setEnabled(false);
}
}
$button->setText($text);
$button->setCommandName($commandName);
$button->setCommandParameter($commandParameter);
$button->setCausesValidation(false);
$button->setCssClass($this->getButtonCssClass());
return $button;
}
/**
* Initializes the specified cell to its initial values.
* This method overrides the parent implementation.
* It creates a command button within the cell.
* @param TTableCell the cell to be initialized.
* @param integer the index to the Columns property that the cell resides in.
* @param string the type of cell (Header,Footer,Item,AlternatingItem,EditItem,SelectedItem)
*/
public function initializeCell($cell, $columnIndex, $itemType)
{
if ($itemType === TListItemType::Item || $itemType === TListItemType::AlternatingItem || $itemType === TListItemType::SelectedItem || $itemType === TListItemType::EditItem) {
$buttonType = $this->getButtonType();
if ($buttonType === TButtonColumnType::LinkButton) {
$button = new TLinkButton();
} else {
if ($buttonType === TButtonColumnType::PushButton) {
$button = new TButton();
} else {
$button = new TImageButton();
$button->setImageUrl($this->getImageUrl());
$button->setToolTip($this->getText());
}
}
$button->setText($this->getText());
$button->setCommandName($this->getCommandName());
$button->setCausesValidation($this->getCausesValidation());
$button->setValidationGroup($this->getValidationGroup());
if ($this->getDataTextField() !== '' || $buttonType === TButtonColumnType::ImageButton && $this->getDataImageUrlField() !== '') {
$button->attachEventHandler('OnDataBinding', array($this, 'dataBindColumn'));
}
$cell->getControls()->add($button);
$cell->registerObject('Button', $button);
} else {
parent::initializeCell($cell, $columnIndex, $itemType);
}
}
/**
* Initializes the header cell.
*
* This method attempts to use {@link getHeaderRenderer HeaderRenderer} to
* instantiate the header cell. If that is not available, it will populate
* the cell with an image or a text string, depending on {@link getHeaderImageUrl HeaderImageUrl}
* and {@link getHeaderText HeaderText} property values.
*
* If the column allows sorting, image or text will be created as
* a button which issues <b>Sort</b> command upon user click.
*
* @param TTableCell the cell to be initialized
* @param integer the index to the Columns property that the cell resides in.
*/
protected function initializeHeaderCell($cell, $columnIndex)
{
$text = $this->getHeaderText();
if (($classPath = $this->getHeaderRenderer()) !== '') {
$control = Prado::createComponent($classPath);
$cell->getControls()->add($control);
if ($control instanceof \Prado\IDataRenderer) {
if ($control instanceof IItemDataRenderer) {
$item = $cell->getParent();
$control->setItemIndex($item->getItemIndex());
$control->setItemType($item->getItemType());
}
$control->setData($text);
}
} else {
if ($this->getAllowSorting()) {
$sortExpression = $this->getSortExpression();
if (($url = $this->getHeaderImageUrl()) !== '') {
$button = new TImageButton();
$button->setImageUrl($url);
$button->setCommandName(TDataGrid::CMD_SORT);
$button->setCommandParameter($sortExpression);
if ($text !== '') {
$button->setAlternateText($text);
}
$button->setCausesValidation(false);
$cell->getControls()->add($button);
} else {
if ($text !== '') {
$button = new TLinkButton();
$button->setText($text);
$button->setCommandName(TDataGrid::CMD_SORT);
$button->setCommandParameter($sortExpression);
$button->setCausesValidation(false);
$cell->getControls()->add($button);
} else {
$cell->setText(' ');
}
}
} else {
if (($url = $this->getHeaderImageUrl()) !== '') {
$image = new TImage();
$image->setImageUrl($url);
if ($text !== '') {
$image->setAlternateText($text);
}
$cell->getControls()->add($image);
} else {
if ($text !== '') {
$cell->setText($text);
} else {
$cell->setText(' ');
}
}
}
}
}
/**
* Creates a button and initializes its properties.
* The button type is determined by {@link getButtonType ButtonType}.
* @param string command name associated with the button
* @param string button caption
* @param boolean whether the button should cause validation
* @param string the validation group that the button belongs to
* @return mixed the newly created button.
*/
protected function createButton($commandName, $text, $causesValidation, $validationGroup)
{
if ($this->getButtonType() === TButtonColumnType::LinkButton) {
$button = new TLinkButton();
} else {
if ($this->getButtonType() === TButtonColumnType::PushButton) {
$button = new TButton();
} else {
$button = new TImageButton();
if (strcasecmp($commandName, 'Update') === 0) {
$url = $this->getUpdateImageUrl();
} else {
if (strcasecmp($commandName, 'Cancel') === 0) {
$url = $this->getCancelImageUrl();
} else {
$url = $this->getEditImageUrl();
}
}
$button->setImageUrl($url);
}
}
$button->setText($text);
$button->setCommandName($commandName);
$button->setCausesValidation($causesValidation);
$button->setValidationGroup($validationGroup);
return $button;
}
/**
* Ensure that the ID attribute is rendered and registers the javascript code
* for initializing the active control.
*/
protected function addAttributesToRender($writer)
{
parent::addAttributesToRender($writer);
$writer->addAttribute('id', $this->getClientID());
$this->getActiveControl()->registerCallbackClientScript($this->getClientClassName(), $this->getPostBackOptions());
}