bundle/Command/InstallCommand.php
protected function askForData($optionIdentifier, $optionName, $defaultValue, $validator = null)
    {
        $optionValue = $this->input->getOption($optionIdentifier);
        $optionValue = !empty($optionValue) ? $optionValue :
            $defaultValue;

        $question = $this->getQuestion($optionName, $optionValue, $validator);
        $optionValue = $this->questionHelper->ask(
            $this->input,
            $this->output,
            $question
        );

        $this->input->setOption($optionIdentifier, $optionValue);

        return $optionValue;
    }
protected function askForData($optionIdentifier, $optionName, $defaultValue, $validator = null)
    {
        $optionValue = $this->input->getOption($optionIdentifier);
        $optionValue = !empty($optionValue) ? $optionValue :
            $defaultValue;

        $question = $this->getQuestion($optionName, $optionValue, $validator);
        $optionValue = $this->questionHelper->ask(
            $this->input,
            $this->output,
            $question
        );

        $this->input->setOption($optionIdentifier, $optionValue);

        return $optionValue;
    }
Asks a question that fills provided option.

@param string $optionIdentifier
@param string $optionName
@param string $defaultValue
@param callable $validator

@return string