core-bundle/src/Resources/contao/widgets/CheckBox.php
protected function generateCheckbox($arrOption, $i)
	{
		return sprintf('<input type="checkbox" name="%s" id="opt_%s" class="tl_checkbox" value="%s"%s%s onfocus="Backend.getScrollOffset()"> <label for="opt_%s">%s%s%s</label>',
						$this->strName . ($this->multiple ? '[]' : ''),
						$this->strId.'_'.$i,
						($this->multiple ? StringUtil::specialchars($arrOption['value']) : 1),
						$this->isChecked($arrOption),
						$this->getAttributes(),
						$this->strId.'_'.$i,
						($this->mandatory && !$this->multiple ? '<span class="invisible">'.$GLOBALS['TL_LANG']['MSC']['mandatory'].' </span>' : ''),
						$arrOption['label'],
						($this->mandatory && !$this->multiple ? '<span class="mandatory">*</span>' : ''));
	}
protected function generateCheckbox($arrOption, $i)
	{
		return sprintf('<input type="checkbox" name="%s" id="opt_%s" class="tl_checkbox" value="%s"%s%s onfocus="Backend.getScrollOffset()"> <label for="opt_%s">%s%s%s</label>',
						$this->strName . ($this->multiple ? '[]' : ''),
						$this->strId.'_'.$i,
						($this->multiple ? StringUtil::specialchars($arrOption['value']) : 1),
						$this->isChecked($arrOption),
						$this->getAttributes(),
						$this->strId.'_'.$i,
						($this->mandatory && !$this->multiple ? '<span class="invisible">'.$GLOBALS['TL_LANG']['MSC']['mandatory'].' </span>' : ''),
						$arrOption['label'],
						($this->mandatory && !$this->multiple ? '<span class="mandatory">*</span>' : ''));
	}
Generate a checkbox and return it as string

@param array   $arrOption
@param integer $i

@return string