silverstripe-framework/src/Forms/FieldList.php

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<?php
namespace SilverStripe\Forms;
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use SilverStripe\Dev\Deprecation;
use SilverStripe\ORM\ArrayList;
/**
* A list designed to hold form field instances.
*
* @method FormField[] getIterator()
*/
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class FieldList extends ArrayList
{
/**
* Cached flat representation of all fields in this set,
* including fields nested in {@link CompositeFields}.
*
* @uses self::collateDataFields()
* @var FormField[]
*/
protected $sequentialSet;
/**
* @var FormField[]
*/
protected $sequentialSaveableSet;
/**
* If this fieldlist is owned by a parent field (e.g. CompositeField)
* this is the parent field.
*
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* @var CompositeField
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*/
protected $containerField;
public function __construct($items = [])
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{
if (!is_array($items) || func_num_args() > 1) {
$items = func_get_args();
}
parent::__construct($items);
foreach ($items as $item) {
if ($item instanceof FormField) {
$item->setContainerFieldList($this);
}
}
}
public function __clone()
{
// Clone all fields in this list
foreach ($this->items as $key => $field) {
$this->items[$key] = clone $field;
}
}
/**
* Iterate over each field in the current list recursively
*
* @param callable $callback
*/
public function recursiveWalk(callable $callback)
{
$stack = $this->toArray();
while (!empty($stack)) {
/** @var FormField $field */
$field = array_shift($stack);
$callback($field);
if ($field instanceof CompositeField) {
$stack = array_merge($field->getChildren()->toArray(), $stack);
}
}
}
/**
* Return a flattened list of all fields
*
* @return static
*/
public function flattenFields()
{
$fields = [];
$this->recursiveWalk(function (FormField $field) use (&$fields) {
$fields[] = $field;
});
return static::create($fields);
}
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/**
* Return a sequential set of all fields that have data. This excludes wrapper composite fields
* as well as heading / help text fields.
*
* @return FormField[]
*/
public function dataFields()
{
if (empty($this->sequentialSet)) {
$fields = [];
$this->recursiveWalk(function (FormField $field) use (&$fields) {
if (!$field->hasData()) {
return;
}
$name = $field->getName();
if (isset($fields[$name])) {
$this->fieldNameError($field, __FUNCTION__);
}
$fields[$name] = $field;
});
$this->sequentialSet = $fields;
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}
return $this->sequentialSet;
}
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/**
* @return FormField[]
*/
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public function saveableFields()
{
if (empty($this->sequentialSaveableSet)) {
$fields = [];
$this->recursiveWalk(function (FormField $field) use (&$fields) {
if (!$field->canSubmitValue()) {
return;
}
$name = $field->getName();
if (isset($fields[$name])) {
$this->fieldNameError($field, __FUNCTION__);
}
$fields[$name] = $field;
});
$this->sequentialSaveableSet = $fields;
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}
return $this->sequentialSaveableSet;
}
/**
* Return array of all field names
*
* @return array
*/
public function dataFieldNames()
{
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return array_keys($this->dataFields() ?? []);
}
/**
* Trigger an error for duplicate field names
*
* @param FormField $field
* @param $functionName
*/
protected function fieldNameError(FormField $field, $functionName)
{
if ($field->getForm()) {
$errorSuffix = sprintf(
" in your '%s' form called '%s'",
get_class($field->getForm()),
$field->getForm()->getName()
);
} else {
$errorSuffix = '';
}
throw new \RuntimeException(sprintf(
"%s() I noticed that a field called '%s' appears twice%s",
$functionName,
$field->getName(),
$errorSuffix
));
}
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protected function flushFieldsCache()
{
$this->sequentialSet = null;
$this->sequentialSaveableSet = null;
}
/**
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* @deprecated 4.1.0 Please use dataFields or saveableFields instead
* @param $list
* @param bool $saveableOnly
*/
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protected function collateDataFields(&$list, $saveableOnly = false)
{
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Deprecation::notice('4.1.0', 'Please use dataFields or saveableFields instead');
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if (!isset($list)) {
$list = [];
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}
/** @var FormField $field */
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foreach ($this as $field) {
if ($field instanceof CompositeField) {
$field->collateDataFields($list, $saveableOnly);
}
if ($saveableOnly) {
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$isIncluded = $field->canSubmitValue();
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} else {
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$isIncluded = $field->hasData();
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}
if ($isIncluded) {
$name = $field->getName();
if (isset($list[$name])) {
if ($this->form) {
$formClass = get_class($this->form);
$errSuffix = " in your '{$formClass}' form called '" . $this->form->Name() . "'";
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} else {
$errSuffix = '';
}
throw new \RuntimeException(
"collateDataFields() I noticed that a field called '$name' appears twice$errSuffix."
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);
}
$list[$name] = $field;
}
}
}
/**
* Add an extra field to a tab within this FieldList.
* This is most commonly used when overloading getCMSFields()
*
* @param string $tabName The name of the tab or tabset. Subtabs can be referred to as TabSet.Tab
* or TabSet.Tab.Subtab. This function will create any missing tabs.
* @param FormField $field The {@link FormField} object to add to the end of that tab.
* @param string $insertBefore The name of the field to insert before. Optional.
*
* @return $this
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*/
public function addFieldToTab($tabName, $field, $insertBefore = null)
{
// This is a cache that must be flushed
$this->flushFieldsCache();
// Find the tab
$tab = $this->findOrMakeTab($tabName);
// Add the field to the end of this set
if ($insertBefore) {
$tab->insertBefore($insertBefore, $field);
} else {
$tab->push($field);
}
return $this;
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}
/**
* Add a number of extra fields to a tab within this FieldList.
* This is most commonly used when overloading getCMSFields()
*
* @param string $tabName The name of the tab or tabset. Subtabs can be referred to as TabSet.Tab
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* or TabSet.Tab.Subtab. This function will create any missing tabs.
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* @param array $fields An array of {@link FormField} objects.
* @param string $insertBefore Name of field to insert before
*
* @return $this
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*/
public function addFieldsToTab($tabName, $fields, $insertBefore = null)
{
$this->flushFieldsCache();
// Find the tab
$tab = $this->findOrMakeTab($tabName);
// Add the fields to the end of this set
foreach ($fields as $field) {
// Check if a field by the same name exists in this tab
if ($insertBefore) {
$tab->insertBefore($insertBefore, $field);
} elseif (($name = $field->getName()) && $tab->fieldByName($name)) {
// It exists, so we need to replace the old one
$this->replaceField($field->getName(), $field);
} else {
$tab->push($field);
}
}
return $this;
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}
/**
* Remove the given field from the given tab in the field.
*
* @param string $tabName The name of the tab
* @param string $fieldName The name of the field
*
* @return $this
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*/
public function removeFieldFromTab($tabName, $fieldName)
{
$this->flushFieldsCache();
// Find the tab
$tab = $this->findTab($tabName);
if ($tab) {
$tab->removeByName($fieldName);
}
return $this;
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}
/**
* Removes a number of fields from a Tab/TabSet within this FieldList.
*
* @param string $tabName The name of the Tab or TabSet field
* @param array $fields A list of fields, e.g. array('Name', 'Email')
*
* @return $this
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*/
public function removeFieldsFromTab($tabName, $fields)
{
$this->flushFieldsCache();
// Find the tab
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if ($tab = $this->findTab($tabName)) {
// Remove the fields from this set
foreach ($fields as $field) {
$tab->removeByName($field);
}
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}
return $this;
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}
/**
* Remove a field or fields from this FieldList by Name.
* The field could also be inside a CompositeField.
*
* @param string|array $fieldName The name of, or an array with the field(s) or tab(s)
* @param boolean $dataFieldOnly If this is true, then a field will only
* be removed if it's a data field. Dataless fields, such as tabs, will
* be left as-is.
*
* @return $this
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*/
public function removeByName($fieldName, $dataFieldOnly = false)
{
if (!$fieldName) {
user_error('FieldList::removeByName() was called with a blank field name.', E_USER_WARNING);
}
// Handle array syntax
if (is_array($fieldName)) {
foreach ($fieldName as $field) {
$this->removeByName($field, $dataFieldOnly);
}
return $this;
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}
$this->flushFieldsCache();
foreach ($this as $i => $child) {
$childName = $child->getName();
if (!$childName) {
$childName = $child->Title();
}
if (($childName == $fieldName) && (!$dataFieldOnly || $child->hasData())) {
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array_splice($this->items, $i ?? 0, 1);
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break;
} elseif ($child instanceof CompositeField) {
$child->removeByName($fieldName, $dataFieldOnly);
}
}
return $this;
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}
/**
* Replace a single field with another. Ignores dataless fields such as Tabs and TabSets
*
* @param string $fieldName The name of the field to replace
* @param FormField $newField The field object to replace with
* @param boolean $dataFieldOnly If this is true, then a field will only be replaced if it's a data field. Dataless
* fields, such as tabs, will be not be considered for replacement.
* @return bool TRUE field was successfully replaced
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* FALSE field wasn't found, nothing changed
*/
public function replaceField($fieldName, $newField, $dataFieldOnly = true)
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{
$this->flushFieldsCache();
foreach ($this as $i => $field) {
if ($field->getName() == $fieldName && (!$dataFieldOnly || $field->hasData())) {
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$this->items[$i] = $newField;
return true;
} elseif ($field instanceof CompositeField) {
if ($field->replaceField($fieldName, $newField)) {
return true;
}
}
}
return false;
}
/**
* Rename the title of a particular field name in this set.
*
* @param string $fieldName Name of field to rename title of
* @param string $newFieldTitle New title of field
* @return bool
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*/
public function renameField($fieldName, $newFieldTitle)
{
$field = $this->dataFieldByName($fieldName);
if (!$field) {
return false;
}
$field->setTitle($newFieldTitle);
return $field->Title() == $newFieldTitle;
}
/**
* @return bool
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*/
public function hasTabSet()
{
foreach ($this->items as $i => $field) {
if (is_object($field) && $field instanceof TabSet) {
return true;
}
}
return false;
}
/**
* Returns the specified tab object, if it exists
*
* @param string $tabName The tab to return, in the form "Tab.Subtab.Subsubtab".
* @return Tab|null The found or null
*/
public function findTab($tabName)
{
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$parts = explode('.', $tabName ?? '');
$last_idx = count($parts ?? []) - 1;
$currentPointer = $this;
foreach ($parts as $k => $part) {
$parentPointer = $currentPointer;
/** @var FormField $currentPointer */
$currentPointer = $currentPointer->fieldByName($part);
}
return $currentPointer;
}
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/**
* Returns the specified tab object, creating it if necessary.
*
* @todo Support recursive creation of TabSets
*
* @param string $tabName The tab to return, in the form "Tab.Subtab.Subsubtab".
* Caution: Does not recursively create TabSet instances, you need to make sure everything
* up until the last tab in the chain exists.
* @param string $title Natural language title of the tab. If {@link $tabName} is passed in dot notation,
* the title parameter will only apply to the innermost referenced tab.
* The title is only changed if the tab doesn't exist already.
* @return Tab The found or newly created Tab instance
*/
public function findOrMakeTab($tabName, $title = null)
{
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$parts = explode('.', $tabName ?? '');
$last_idx = count($parts ?? []) - 1;
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// We could have made this recursive, but I've chosen to keep all the logic code within FieldList rather than
// add it to TabSet and Tab too.
$currentPointer = $this;
foreach ($parts as $k => $part) {
$parentPointer = $currentPointer;
/** @var FormField $currentPointer */
$currentPointer = $currentPointer->fieldByName($part);
// Create any missing tabs
if (!$currentPointer) {
if ($parentPointer instanceof TabSet) {
// use $title on the innermost tab only
if ($k == $last_idx) {
$currentPointer = isset($title) ? new Tab($part, $title) : new Tab($part);
} else {
$currentPointer = new TabSet($part);
}
$parentPointer->push($currentPointer);
} else {
$withName = $parentPointer instanceof FormField
? " named '{$parentPointer->getName()}'"
: null;
$parentPointerClass = get_class($parentPointer);
throw new \InvalidArgumentException(
"FieldList::addFieldToTab() Tried to add a tab to object"
. " '{$parentPointerClass}'{$withName} - '{$part}' didn't exist."
);
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}
}
}
return $currentPointer;
}
/**
* Returns a named field.
* You can use dot syntax to get fields from child composite fields
*
* @todo Implement similarly to dataFieldByName() to support nested sets - or merge with dataFields()
*
* @param string $name
* @return FormField|null
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*/
public function fieldByName($name)
{
$fullName = $name;
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if (strpos($name ?? '', '.') !== false) {
list($name, $remainder) = explode('.', $name ?? '', 2);
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} else {
$remainder = null;
}
foreach ($this as $child) {
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if (trim($fullName ?? '') == trim($child->getName() ?? '') || $fullName == $child->id) {
return $child;
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} elseif (trim($name ?? '') == trim($child->getName() ?? '') || $name == $child->id) {
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if ($remainder) {
if ($child instanceof CompositeField) {
return $child->fieldByName($remainder);
} else {
$childClass = get_class($child);
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user_error(
"Trying to get field '{$remainder}' from non-composite field {$childClass}.{$name}",
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E_USER_WARNING
);
return null;
}
} else {
return $child;
}
}
}
return null;
}
/**
* Returns a named field in a sequential set.
* Use this if you're using nested FormFields.
*
* @param string $name The name of the field to return
* @return FormField|null
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*/
public function dataFieldByName($name)
{
if ($dataFields = $this->dataFields()) {
foreach ($dataFields as $child) {
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if (trim($name ?? '') == trim($child->getName() ?? '') || $name == $child->id) {
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return $child;
}
}
}
return null;
}
/**
* Inserts a field before a particular field in a FieldList.
* Will traverse CompositeFields depth-first to find the matching $name, and insert before the first match
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*
* @param string $name Name of the field to insert before
* @param FormField $item The form field to insert
* @param bool $appendIfMissing Append to the end of the list if $name isn't found
* @return FormField|false Field if it was successfully inserted, false if not inserted
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*/
public function insertBefore($name, $item, $appendIfMissing = true)
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{
// Backwards compatibility for order of arguments
if ($name instanceof FormField) {
Deprecation::notice('5.0', 'Incorrect order of arguments for insertBefore');
list($item, $name) = [$name, $item];
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}
$this->onBeforeInsert($item);
$item->setContainerFieldList($this);
$i = 0;
foreach ($this as $child) {
if ($name == $child->getName() || $name == $child->id) {
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array_splice($this->items, $i ?? 0, 0, [$item]);
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return $item;
} elseif ($child instanceof CompositeField) {
$ret = $child->insertBefore($name, $item, false);
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if ($ret) {
return $ret;
}
}
$i++;
}
// $name not found, append if needed
if ($appendIfMissing) {
$this->push($item);
return $item;
}
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return false;
}
/**
* Inserts a field after a particular field in a FieldList.
* Will traverse CompositeFields depth-first to find the matching $name, and insert after the first match
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*
* @param string $name Name of the field to insert after
* @param FormField $item The form field to insert
* @param bool $appendIfMissing Append to the end of the list if $name isn't found
* @return FormField|false Field if it was successfully inserted, false if not inserted
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*/
public function insertAfter($name, $item, $appendIfMissing = true)
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{
// Backwards compatibility for order of arguments
if ($name instanceof FormField) {
Deprecation::notice('5.0', 'Incorrect order of arguments for insertAfter');
list($item, $name) = [$name, $item];
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}
$this->onBeforeInsert($item);
$item->setContainerFieldList($this);
$i = 0;
foreach ($this as $child) {
if ($name == $child->getName() || $name == $child->id) {
array_splice($this->items, $i+1, 0, [$item]);
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return $item;
} elseif ($child instanceof CompositeField) {
$ret = $child->insertAfter($name, $item, false);
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if ($ret) {
return $ret;
}
}
$i++;
}
// $name not found, append if needed
if ($appendIfMissing) {
$this->push($item);
return $item;
}
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return false;
}
/**
* Push a single field onto the end of this FieldList instance.
*
* @param FormField $item The FormField to add
*/
public function push($item)
{
$this->onBeforeInsert($item);
$item->setContainerFieldList($this);
return parent::push($item);
}
/**
* Push a single field onto the beginning of this FieldList instance.
*
* @param FormField $item The FormField to add
*/
public function unshift($item)
{
$this->onBeforeInsert($item);
$item->setContainerFieldList($this);
return parent::unshift($item);
}
/**
* Handler method called before the FieldList is going to be manipulated.
*
* @param FormField $item
*/
protected function onBeforeInsert($item)
{
$this->flushFieldsCache();
if ($item->getName()) {
$this->rootFieldList()->removeByName($item->getName(), true);
}
}
/**
* Set the Form instance for this FieldList.
*
* @param Form $form The form to set this FieldList to
* @return $this
*/
public function setForm($form)
{
foreach ($this as $field) {
$field->setForm($form);
}
return $this;
}
/**
* Load the given data into this form.
*
* @param array $data An map of data to load into the FieldList
* @return $this
*/
public function setValues($data)
{
foreach ($this->dataFields() as $field) {
$fieldName = $field->getName();
if (isset($data[$fieldName])) {
$field->setValue($data[$fieldName]);
}
}
return $this;
}
/**
* Return all <input type="hidden"> fields
* in a form - including fields nested in {@link CompositeFields}.
* Useful when doing custom field layouts.
*
* @return FieldList
*/
public function HiddenFields()
{
$hiddenFields = new FieldList();
$dataFields = $this->dataFields();
if ($dataFields) {
foreach ($dataFields as $field) {
if ($field instanceof HiddenField) {
$hiddenFields->push($field);
}
}
}
return $hiddenFields;
}
/**
* Return all fields except for the hidden fields.
* Useful when making your own simplified form layouts.
*/
public function VisibleFields()
{
$visibleFields = new FieldList();
foreach ($this as $field) {
if (!($field instanceof HiddenField)) {
$visibleFields->push($field);
}
}
return $visibleFields;
}
/**
* Transform this FieldList with a given transform method,
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* e.g. $this->transform(new ReadonlyTransformation())
*
* @param FormTransformation $trans
* @return FieldList
*/
public function transform($trans)
{
$this->flushFieldsCache();
$newFields = new FieldList();
foreach ($this as $field) {
$newFields->push($field->transform($trans));
}
return $newFields;
}
/**
* Returns the root field set that this belongs to
*
* @return FieldList|FormField
*/
public function rootFieldList()
{
if ($this->containerField) {
return $this->containerField->rootFieldList();
}
return $this;
}
/**
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* @return CompositeField|null
*/
public function getContainerField()
{
return $this->containerField;
}
/**
* @param CompositeField|null $field
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* @return $this
*/
public function setContainerField($field)
{
$this->containerField = $field;
return $this;
}
/**
* Transforms this FieldList instance to readonly.
*
* @return FieldList
*/
public function makeReadonly()
{
return $this->transform(new ReadonlyTransformation());
}
/**
* Transform the named field into a readonly field.
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*
* @param string|array|FormField $field
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*/
public function makeFieldReadonly($field)
{
if (!is_array($field)) {
$field = [$field];
}
foreach ($field as $item) {
$fieldName = ($item instanceof FormField) ? $item->getName() : $item;
$srcField = $this->dataFieldByName($fieldName);
if ($srcField) {
$this->replaceField($fieldName, $srcField->performReadonlyTransformation());
} else {
user_error("Trying to make field '$fieldName' readonly, but it does not exist in the list", E_USER_WARNING);
}
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}
}
/**
* Change the order of fields in this FieldList by specifying an ordered list of field names.
* This works well in conjunction with SilverStripe's scaffolding functions: take the scaffold, and
* shuffle the fields around to the order that you want.
*
* Please note that any tabs or other dataless fields will be clobbered by this operation.
*
* @param array $fieldNames Field names can be given as an array, or just as a list of arguments.
*/
public function changeFieldOrder($fieldNames)
{
// Field names can be given as an array, or just as a list of arguments.
if (!is_array($fieldNames)) {
$fieldNames = func_get_args();
}
// Build a map of fields indexed by their name. This will make the 2nd step much easier.
$fieldMap = [];
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foreach ($this->dataFields() as $field) {
$fieldMap[$field->getName()] = $field;
}
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// Iterate through the ordered list of names, building a new array to be put into $this->items.
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// While we're doing this, empty out $fieldMap so that we can keep track of leftovers.
// Unrecognised field names are okay; just ignore them
$fields = [];
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foreach ($fieldNames as $fieldName) {
if (isset($fieldMap[$fieldName])) {
$fields[] = $fieldMap[$fieldName];
unset($fieldMap[$fieldName]);
}
}
// Add the leftover fields to the end of the list.
$fields = array_values($fields + $fieldMap);
// Update our internal $this->items parameter.
$this->items = $fields;
$this->flushFieldsCache();
}
/**
* Find the numerical position of a field within
* the children collection. Doesn't work recursively.
*
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* @param string|FormField $field
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* @return int Position in children collection (first position starts with 0).
* Returns FALSE if the field can't be found.
*/
public function fieldPosition($field)
{
if ($field instanceof FormField) {
$field = $field->getName();
}
$i = 0;
foreach ($this->dataFields() as $child) {
if ($child->getName() == $field) {
return $i;
}
$i++;
}
return false;
}
/**
* Default template rendering of a FieldList will concatenate all FieldHolder values.
*/
public function forTemplate()
{
$output = "";
foreach ($this as $field) {
$output .= $field->FieldHolder();
}
return $output;
}
}