QMediaPlayer不會在Ubuntu 16.04/Qt的5.6

Question

我使用的是在Ubuntu 16.04正式的Qt 5.6的SDK玩什麼，當我嘗試播放MP3文件我只是得到：

defaultServiceProvider::requestService(): no service found for - "org.qt-project.qt.mediaplayer" 

的代碼儘可能簡單：

mMediaPlayer->setMedia(QUrl::fromLocalFile(myMp3File)); 
mMediaPlayer->play(); 

這適用於Android，它在我的Ubuntu 14.04機器上工作過。我錯過了什麼？所有必需的GStreamer（通過文檔）的東西似乎默認已經安裝，但它仍然不能正常工作：

$ dpkg -l | grep gstream 
ii gir1.2-gstreamer-1.0         1.8.2-1~ubuntu1            amd64  GObject introspection data for the GStreamer library 
ii gstreamer1.0-alsa:amd64        1.8.2-1ubuntu0.1           amd64  GStreamer plugin for ALSA 
ii gstreamer1.0-clutter-3.0        3.0.18-1             amd64  Clutter PLugin for GStreamer 1.0 
ii gstreamer1.0-fluendo-mp3:amd64      0.10.32.debian-1           amd64  Fluendo mp3 decoder GStreamer 1.0 plugin 
ii gstreamer1.0-libav:amd64        1.8.2-1~ubuntu1            amd64  libav plugin for GStreamer 
ii gstreamer1.0-plugins-bad:amd64      1.8.2-1ubuntu0.1           amd64  GStreamer plugins from the "bad" set 
ii gstreamer1.0-plugins-bad-faad:amd64     1.8.2-1ubuntu0.1           amd64  GStreamer faad plugin from the "bad" set 
ii gstreamer1.0-plugins-bad-videoparsers:amd64   1.8.2-1ubuntu0.1           amd64  GStreamer videoparsers plugin from the "bad" set 
ii gstreamer1.0-plugins-base:amd64      1.8.2-1ubuntu0.1           amd64  GStreamer plugins from the "base" set 
ii gstreamer1.0-plugins-base-apps      1.8.2-1ubuntu0.1           amd64  GStreamer helper programs from the "base" set 
ii gstreamer1.0-plugins-good:amd64      1.8.2-1ubuntu0.1           amd64  GStreamer plugins from the "good" set 
ii gstreamer1.0-plugins-ugly:amd64      1.8.2-1ubuntu0.1           amd64  GStreamer plugins from the "ugly" set 
ii gstreamer1.0-plugins-ugly-amr:amd64     1.8.2-1ubuntu0.1           amd64  GStreamer plugins from the "ugly" set 
ii gstreamer1.0-pulseaudio:amd64      1.8.2-1ubuntu0.1           amd64  GStreamer plugin for PulseAudio 
ii gstreamer1.0-tools         1.8.2-1~ubuntu1            amd64  Tools for use with GStreamer 
ii gstreamer1.0-x:amd64         1.8.2-1ubuntu0.1           amd64  GStreamer plugins for X11 and Pango 
ii libgstreamer-plugins-bad1.0-0:amd64     1.8.2-1ubuntu0.1           amd64  GStreamer development files for libraries from the "bad" set 
ii libgstreamer-plugins-base1.0-0:amd64     1.8.2-1ubuntu0.1           amd64  GStreamer libraries from the "base" set 
ii libgstreamer-plugins-good1.0-0:amd64     1.8.2-1ubuntu0.1           amd64  GStreamer development files for libraries from the "good" set 
ii libgstreamer1.0-0:amd64        1.8.2-1~ubuntu1            amd64  Core GStreamer libraries and elements 
ii libreoffice-avmedia-backend-gstreamer    1:5.1.4-0ubuntu1           amd64  GStreamer backend for LibreOffice 

...當然還有我的聲音工作，否則完美。

Answer 1

首先，使用QT_DEBUG_PLUGINS = 1運行您的應用程序以查看插件錯誤。

如果您發現有關「libgstaudio-0.10.so.0」的錯誤，這是一個GStreamer版本問題。官方的Qt二進制文件似乎需要GStreamer 0.10。

解決方案，我發現：

• 使用隨附分佈libqt，用你的包管理器：這是我找到了最好的解決方案，因爲它是用正確的GStreamer版本內置。我使用不同的chroot爲包含不同GStreamer版本的發行版打包。
• Compile Qt from source to enable Gstreamer 1.0：未測試
• 安裝Gstreamer 0.10：我不推薦使用此選項，或者如果您需要使用舊版本的分發版，請使用chroot。