Qt qgraphicsvideoitem编译器错误

Question

我正在尝试使用QMediaPlayer播放视频。目前我正在使用QT主页中的示例：

http://qt-project.org/doc/qt-5.0/qtmultimedia/videooverview.html

player = new QMediaPlayer(this);

QGraphicsVideoItem *item = new QGraphicsVideoItem;
player->setVideoOutput(item);
graphicsView->scene()->addItem(item);
graphicsView->show();

player->setMedia(QUrl("http://example.com/myclip4.ogv"));
player->play();

当我尝试编译此代码时，我收到此错误：

C:\Users\Philipp\Desktop\CarPC_Terminal\mainwindow.cpp:220: Fehler:undefined reference to `_imp___ZN18QGraphicsVideoItemC1EP13QGraphicsItem'

有人可以告诉我要解决这个问题需要做些什么吗？

我的包括：

#include <QMainWindow>
#include <QtMultimedia>
#include <QtMultimediaWidgets/QVideoWidget>
#include <QtMultimediaWidgets/QGraphicsVideoItem>
#include <QtWidgets/QGraphicsItem>
#include <QGraphicsView>

这是调试器的输出：

Debuggen beginnt
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\platforms\qminimald.dll"
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\platforms\qoffscreend.dll"
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\platforms\qwindowsd.dll"
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\mediaservice\dsengined.dll"
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\mediaservice\qtmedia_audioengined.dll"
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\accessible\qtaccessiblequickd.dll"
Temporarily disabling breakpoints for unloaded shared library "C:\Qt\Qt5.1.0\5.1.0\mingw48_32\plugins\accessible\qtaccessiblewidgetsd.dll"
(Internal error: pc 0x4 in read in psymtab, but not in symtab.)
(Internal error: pc 0x4 in read in psymtab, but not in symtab.)