QtPDF 是 Qt 封装的 pdfium 模块，以 GPLv3/LGPLv3 协议分发，也可以在 QT marketplace 购买可商业版本
下载源代码
git clone <https://code.qt.io/qt/qtwebengine.git>
cd qtwebengine
git checkout 5.12.8
git submodule update --init --recursive
注意：git checkout 选择自己 qt 的版本
安装构建依赖
sudo apt install bison build-essential gperf flex python2 libasound2-dev libcups2-dev libdrm-dev libegl1-mesa-dev libnss3-dev libpci-dev libpulse-dev libudev-dev nodejs libxtst-dev gyp ninja-build
sudo apt install libssl-dev libxcursor-dev libxcomposite-dev libxdamage-dev libxrandr-dev libfontconfig1-dev libxss-dev libsrtp2-dev libwebp-dev libjsoncpp-dev libopus-dev libminizip-dev libavutil-dev libavformat-dev libavcodec-dev libevent-dev libvpx-dev libsnappy-dev libre2-dev libprotobuf-dev protobuf-compile
如果报错 Project ERROR: Unknown module(s) in QT: qml-private， 需要安装 qtdeclarative5-dev
编译
cd ..
mkdir build
cd build
qmake ../qtwebengine
NINJAJOBS=-j7 make -j7
make install
下面是 qmake 的输出信息，如果依赖安装不全可以参考一下
Running configuration tests...
Done running configuration tests.
Configure summary:
Qt WebEngine:
Embedded build ......................... no
Full debug information ................. no
Pepper Plugins ......................... yes
Printing and PDF ....................... yes
Proprietary Codecs ..................... no
Spellchecker ........................... yes
Native Spellchecker .................... no
WebRTC ................................. yes
Use System Ninja ....................... no
Geolocation ............................ yes
WebChannel support ..................... yes
Use v8 snapshot ........................ yes
Kerberos Authentication ................ no
Support qpa-xcb ........................ yes
Use ALSA ............................... yes
Use PulseAudio ......................... yes
Optional system libraries used:
re2 .................................. yes
icu .................................. no
libwebp, libwebpmux and libwebpdemux . yes
opus ................................. yes
ffmpeg ............................... no
libvpx ............................... yes
snappy ............................... yes
glib ................................. yes
zlib ................................. yes
minizip .............................. yes
libevent ............................. yes
jsoncpp .............................. yes
protobuf ............................. yes
libxml2 and libxslt .................. yes
lcms2 ................................ yes
png .................................. yes
JPEG ................................. yes
harfbuzz ............................. yes
freetype ............................. yes
Required system libraries:
fontconfig ........................... yes
dbus ................................. yes
nss .................................. yes
khr .................................. yes
glibc ................................ yes
Required system libraries for qpa-xcb:
x11 .................................. yes
libdrm ............................... yes
xcomposite ........................... yes
xcursor .............................. yes
xi ................................... yes
xtst ................................. yes
Qt is now configured for building. Just run 'make'.
Once everything is built, you must run 'make install'.
Qt will be installed into '/usr'.
Prior to reconfiguration, make sure you remove any leftovers from
the previous build.
编译过程需要2-3个小时，内存占用高峰大概需要16G + 5G swap
使用测试
QT += core gui widgets pdf pdfwidgets
如果能正常识别，说明配置成功了，可以试试下面这个例子：
https://github.com/CryFeiFei/QtPdfTest
