Error by PrefillMultiFieldViewHelper - false values after backend validation errors

[GANDJUBAS]

Problem: We have some radio fields with some values (e.g. 0,1,2,3). Value 2 is preselected. In the GUI we select radio with value 1 and submit our form. Our backend validator notes some errors cause other fields are incorrect. We see error description and value 2 is optically selected by our radios again. In html code we can see that both option (1 and 2) are cheched.

Reason: Boolean value "false" is unhandled in the function buildSelectedValue. Option can not be unchecked if some prefill or other setting exists. It overwrite this.

My Solution:

protected function buildSelectedValue()
{
	$selected = $this->getFromMail();

	if ($selected === null) {
		$selected = $this->getFromMarker();
	}
	if ($selected === null) {
		$selected = $this->getFromRawMarker();
	}
	if ($selected === null) {
		$selected = $this->getFromFieldUid();
	}
	if ($selected === null) {
		$selected = $this->getFromOldPowermailFieldUid();
	}
	if ($selected === null) {
		$selected = $this->getFromFrontendUser();
	}
	if ($selected === null) {
		$selected = $this->getFromPrefillValue();
	}
	if ($selected === null) {
		$selected = $this->getFromTypoScriptContentObject();
	}
	if ($selected === null) {
		$selected = $this->getFromTypoScriptRaw();
	}
	if ($selected === null) {
		$selected = $this->getFromSession();
	}
	$this->setSelected($selected ?? false);
}

...

protected function getFromMail()
{
	$selected = null;
	if ($this->getMail() !== null && $this->getMail()->getAnswers()) {
		$selected = false;
		foreach ($this->getMail()->getAnswers() as $answer) {
			if ($answer->getField() === $this->getField()) {
				$values = $answer->getValue();
				foreach ((array)$values as $value) {
					if ($value === $this->options[$this->index]['value'] ||
						$value === $this->options[$this->index]['label']
					) {
						return true;
					}
				}
			}
		}
	}
	return $selected;
}

...

protected function getFromMarker()
{
	$selected = null;
	if (isset($this->variables['field'][$this->getMarker()])) {
		$selected = false;
		if (is_array($this->variables['field'][$this->getMarker()])) {
			foreach (array_keys($this->variables['field'][$this->getMarker()]) as $key) {
				if ($this->variables['field'][$this->getMarker()][$key] === $this->options[$this->index]['value'] ||
					$this->variables['field'][$this->getMarker()][$key] === $this->options[$this->index]['label']
				) {
					return true;
				}
			}
		} else {
			if ($this->variables['field'][$this->getMarker()] === $this->options[$this->index]['value'] ||
				$this->variables['field'][$this->getMarker()] === $this->options[$this->index]['label']
			) {
				return true;
			}
		}
	}
	return $selected;
}

//and so on

PS: PrefillFieldViewHelper has the same Problem. If we have some prefill value by text field an we try to save empty string we get out prefill value by validation error again.

[mschwemer]

Thanks for your findings and your explanation. :-)

Patch is coming.

[mschwemer]

We need a better solution for this ... therefore I reverted the commit.