Qt 插件：从 qmake 到 qbs。联动错误

Posted 2023-02-17

【中文标题】Qt 插件：从 qmake 到 qbs。联动错误

【英文标题】：Qt plugin: From qmake to qbs. Linkage error

【发布时间】：2017-05-26 08:38:06

【问题描述】：

我有一个包含两个产品的 .pro 项目：

player.pro

TEMPLATE = subdirs
SUBDIRS = mediaplayer \
          imageplayer 
imageplayer.depends = mediaplayer

madiaplayer.pro - dll 库

TEMPLATE = lib
DEFINES += MEDIAPLAYER_LIBRARY
HEADERS = MediaPlayer_global.h \ <...>
<...>

imageplayer.pro - qt 插件

TEMPLATE = lib
CONFIG += plugin
LIBS *= -L<path to mediaplayer dll>
INCLUDEPATH *= mediaplayer \ <...>
DEPENDPATH *= $$INCLUDEPATH
<...>

它工作正常。但是现在我需要qbs版本。

---

我写的是这样的：

player.qbs

Project 
    references: [
        "mediaplayer/MediaPlayer.qbs",
        "imageplayer/ImagePlayer.qbs",
    ]

MediaPlayer.qbs

MediaPlayer 
    Group 
        qbs.install: true
        fileTagsFilter: "dynamiclibrary"
    
    cpp.includePaths: product.sourceDirectory
    cpp.defines: [ product.name.toUpperCase() + "_LIBRARY", ]
    Export 
        cpp.includePaths: product.sourceDirectory
        cpp.defines: [ product.name.toUpperCase() + "_LIBRARY", ]
    
    <...>

ImagePlayer.qbs

ImagePlayer 
    Depends  name: "MediaPlayer" 
    Export  Depends  name: "MediaPlayer"  

    Group 
        qbs.install: true
        fileTagsFilter: "dynamiclibrary"
    
    cpp.includePaths: product.sourceDirectory
    cpp.defines: [ product.name.toUpperCase() + "_LIBRARY", ]
    Export 
        cpp.includePaths: product.sourceDirectory
        cpp.defines: [ product.name.toUpperCase() + "_LIBRARY", ]
    
    <...>

MediaPlayer.h

#include "MediaPlayer_global.h"
#include "MediaPlayerInterface.h"

class MEDIAPLAYERSHARED_EXPORT MediaPlayer : public QWidget, public MediaPlayerInterface

    Q_OBJECT
    Q_INTERFACES(MediaPlayerInterface)
    <...>

ImagePlayer.h

#include "../mediaplayer/MediaPlayer.h"

class ImagePlayer : public MediaPlayer

    Q_OBJECT
    Q_INTERFACES(MediaPlayerInterface)
    Q_PLUGIN_METADATA(IID "org.geeksoft.qt.MediaPlayerInterface")
    <...>

但是...我得到了一个非常不清楚的错误结果（它是 ImagePlayer.dll 链接阶段）：

ImagePlayer.cpp.obj: 未解析的外部符号“public: static struct QMetaObject const MediaPlayer::staticMetaObject” (?staticMetaObject@MediaPlayer@@2UQMetaObject@@B)

moc_ImagePlayer.cpp.obj: 未解析的外部符号“public: static struct QMetaObject const MediaPlayer::staticMetaObject”(?staticMetaObject@MediaPlayer@@2UQMetaObject@@B)

有人知道出了什么问题吗？

【参考方案1】：

这部分看起来很可疑：

Export 
    // ...
    cpp.defines: [ product.name.toUpperCase() + "_LIBRARY", ]

您不太可能真的想导出此定义，因为它可能控制库的头文件之一中某些 EXPORT 预处理器标记的值（我不能肯定地说，因为我不知道您的项目)。只需从 Export 项中删除此行即可。