public function testTitleVisibility()
{
$oPhpPresentation = new PhpPresentation();
$oSlide = $oPhpPresentation->getActiveSlide();
$oShape = $oSlide->createChartShape();
$oLine = new Line();
$oShape->getPlotArea()->setType($oLine);
$elementTitle = '/office:document-content/office:body/office:chart/chart:chart/chart:title';
$elementStyle = '/office:document-content/office:automatic-styles/style:style[@style:name=\'styleTitle\']';
$this->assertTrue($oShape->getTitle()->isVisible());
$this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $oShape->getTitle()->setVisible(true));
$oXMLDoc = TestHelperDOCX::getDocument($oPhpPresentation, 'ODPresentation');
$this->assertTrue($oXMLDoc->elementExists($elementTitle, 'Object 1/content.xml'));
$this->assertTrue($oXMLDoc->elementExists($elementStyle, 'Object 1/content.xml'));
$this->assertInstanceOf('PhpOffice\\PhpPresentation\\Shape\\Chart\\Title', $oShape->getTitle()->setVisible(false));
$oXMLDoc = TestHelperDOCX::getDocument($oPhpPresentation, 'ODPresentation');
$this->assertFalse($oXMLDoc->elementExists($elementTitle, 'Object 1/content.xml'));
$this->assertFalse($oXMLDoc->elementExists($elementStyle, 'Object 1/content.xml'));
}