libmediainfo:qt5 项目未定义的符号错误

Question

我正在尝试在我的qt5项目中使用libmediainfo，但收到以下错误

Undefined symbols for architecture x86_64:
  "MediaInfoLib::MediaInfo::Open(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&)", referenced from:
      MainWindow::on_dupeslistWidget_itemClicked(QListWidgetItem*) in mainwindow.o
  "MediaInfoLib::MediaInfo::Option(std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&, std::basic_string<wchar_t, std::char_traits<wchar_t>, std::allocator<wchar_t> > const&)", referenced from:
      MainWindow::on_dupeslistWidget_itemClicked(QListWidgetItem*) in mainwindow.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [VideoTwin.app/Contents/MacOS/VideoTwin] Error 1
19:56:12: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project VideoTwin (kit: default)
When executing step "Make"

我的 .pro 文件

QT       += core gui
QT += sql
QT += concurrent
QT += multimedia multimediawidgets
INCLUDEPATH += /usr/local/include /usr/local/Cellar/opencv3/3.1.0_1/include/ $$[QT_INSTALL_PREFIX]/src/3rdparty/sqlite
LIBS += -L/usr/local/Cellar/opencv3/3.1.0_1/lib -L/usr/local/lib -lmediainfo -lzen -lz -lpthread -lopencv_stitching -lopencv_superres -lopencv_videostab -lopencv_aruco -lopencv_bgsegm -lopencv_bioinspired -lopencv_ccalib -lopencv_cvv -lopencv_dnn -lopencv_dpm -lopencv_fuzzy -lopencv_line_descriptor -lopencv_optflow -lopencv_plot -lopencv_reg -lopencv_saliency -lopencv_stereo -lopencv_structured_light -lopencv_rgbd -lopencv_surface_matching -lopencv_tracking -lopencv_datasets -lopencv_text -lopencv_face -lopencv_xfeatures2d -lopencv_shape -lopencv_video -lopencv_ximgproc -lopencv_calib3d -lopencv_features2d -lopencv_flann -lopencv_xobjdetect -lopencv_objdetect -lopencv_ml -lopencv_xphoto -lopencv_highgui -lopencv_videoio -lopencv_imgcodecs -lopencv_photo -lopencv_imgproc -lopencv_core
QMAKE_CXXFLAGS += -D_UNICODE -DUNICODE
QMAKE_CFLAGS += -D_UNICODE -DUNICODE
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
TARGET = VideoTwin
TEMPLATE = app

SOURCES += main.cpp
        mainwindow.cpp 
    preferencsedialog.cpp 
    myqlistwidget.cpp 
    $$[QT_INSTALL_PREFIX]/src/3rdparty/sqlite/sqlite3.c 
    matchpair.cpp
HEADERS  += mainwindow.h 
    preferencsedialog.h 
    myqlistwidget.h 
    matchpair.h
FORMS    += mainwindow.ui 
    preferencsedialog.ui
RESOURCES += 
    resources.qrc

在我的头文件中

#include <MediaInfo/MediaInfo.h>

以及CPP的相关部分

MediaInfoLib::MediaInfo media_info;
media_info.Option(L"Internet",L"No");
media_info.Open(item->data(Qt::UserRole + FilepathRole).toString().toStdWString());
QString temp = QString::fromWCharArray( media_info.Inform().c_str(),media_info.Inform().length());
ui->video_info->setText(temp);
ui->video_info->show();

我不确定问题出在哪里。我在/usr/local/lib 目录中有 libmediaplayer.dylib。请帮忙

Answer 1

链接到静态库并使用"dll"头文件为我做了一个技巧：

把它放到你的源代码中

#include "MediaInfoDLL/MediaInfoDLL_Static.h"
using namespace MediaInfoDLL;

这是 .pro 文件的内容

QT += core
QT -= gui
TARGET = QtTestMediaInfo
CONFIG += console
CONFIG -= app_bundle
TEMPLATE = app
SOURCES += main.cpp
# Adjust this to where you put the source code of MediaInfo
MEDIA_INFO_DIR=~/Downloads/MediaInfo_CLI_GNU_FromSource
#INCLUDEPATH += $${MEDIA_INFO_DIR}/ZenLib/Source
INCLUDEPATH += $${MEDIA_INFO_DIR}/MediaInfoLib/Source
LIBS += -L$${MEDIA_INFO_DIR}/MediaInfoLib/Project/GNU/Library -lmediainfo
LIBS += -L$${MEDIA_INFO_DIR}/ZenLib/Project/GNU/Library -lzen -lz

祝你好运！

Answer 2

你不是在对Qt说libmediainfo.dylib在哪里，所以Qt找不到它。

您需要将其添加到您的 .pro 文件中，例如：

LIBS += $$system(pkg-config --libs libmediainfo)

您可以有更多关于如何配置 .pro 文件以链接到 libmediainfo.dylib 的示例，具体取决于 libmediainfo.dylib 在系统上的位置。