找不到 Qt 平台插件 xcb，在 Qt5 上从 Linux 上的源构建

Question

我在 Debian 10 32 位上构建 Qt5。 然后我创建了一个最小的 Qt 项目，运行$ ~/qt/qt-everywhere-src-5.12.7/qtbase/bin/qmake project.pro和make ，但是当我尝试执行应用程序时我 go 如下：

这是怎么回事？

$ ./release/project 
qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in ""
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: linuxfb, minimal, offscreen, vnc, webgl.

Aborted

更多信息：

$ QT_DEBUG_PLUGINS=1 release/project 
QFactoryLoader::QFactoryLoader() checking directory path "/home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms" ...
QFactoryLoader::QFactoryLoader() looking at "/home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqlinuxfb.so"
Found metadata in lib /home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqlinuxfb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "linuxfb"
        ]
    },
    "archreq": 0,
    "className": "QLinuxFbIntegrationPlugin",
    "debug": false,
    "version": 330752
}


Got keys from plugin meta data ("linuxfb")
QFactoryLoader::QFactoryLoader() looking at "/home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqminimal.so"
Found metadata in lib /home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqminimal.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimal"
        ]
    },
    "archreq": 0,
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 330752
}


Got keys from plugin meta data ("minimal")
QFactoryLoader::QFactoryLoader() looking at "/home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqoffscreen.so"
Found metadata in lib /home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqoffscreen.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "offscreen"
        ]
    },
    "archreq": 0,
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 330752
}


Got keys from plugin meta data ("offscreen")
QFactoryLoader::QFactoryLoader() looking at "/home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqvnc.so"
Found metadata in lib /home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqvnc.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vnc"
        ]
    },
    "archreq": 0,
    "className": "QVncIntegrationPlugin",
    "debug": false,
    "version": 330752
}


Got keys from plugin meta data ("vnc")
QFactoryLoader::QFactoryLoader() looking at "/home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqwebgl.so"
Found metadata in lib /home/user/qt/qt-everywhere-src-5.12.7/qtbase/plugins/platforms/libqwebgl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "webgl"
        ]
    },
    "archreq": 0,
    "className": "QWebGLIntegrationPlugin",
    "debug": false,
    "version": 330752
}


Got keys from plugin meta data ("webgl")
QFactoryLoader::QFactoryLoader() checking directory path "/home/user/QtProjects/project/release/platforms" ...
qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in ""
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: linuxfb, minimal, offscreen, vnc, webgl.

Aborted

Answer 1

libqxcb.so应该在应用程序的platforms子目录中找到。 如果您想更改其搜索位置，请查看qt.conf ini 文件，该文件控制插件搜索路径以及其他路径