Raspbian 上的 PyQt5：不显示 QWidgets 的背景颜色

Question

我已经在运行 Raspbian Buster 的 Raspberry Pi 3B+ 上编译并安装了 PyQt5，如此处所述。虽然花了几个小时，但成功了。之后我上传了我的简单 PyQt 示例程序，其中包含 2 个文件（

main.py

和

mainwindow.ui

）。

在我运行 Ubuntu 18.04 LTS 的电脑上，为

QProgressBar

和

QPushButton

设置的红色背景色以不同深浅的红色 (?) 显示，但在 Raspberry Pi 上根本不显示。

Raspbian Buster 上的终端输出：

libEGL warning: DRI2: failed to authenticate
qt5ct: using qt5ct plugin
qt5ct: D-Bus global menu: no

Ubuntu 18.04 LTS 上的屏幕截图：

Raspbian Buster 截图：

为什么 Raspbian Buster 上不显示红色背景颜色？

main.py

import sys
from pathlib import Path
from PyQt5.QtWidgets import QApplication, QMainWindow
from PyQt5.QtGui import QColor
from PyQt5.uic import loadUi


class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super().__init__(parent)
        ui_file = (Path(__file__).parent / "mainwindow.ui").resolve()
        loadUi(ui_file, self)
        self.progressBar.setStyleSheet(f"background-color: {QColor('red').name()}")


def main():
    app = QApplication(sys.argv)
    main_window = MainWindow()
    main_window.show()
    sys.exit(app.exec_())


if __name__ == "__main__":
    main()

主窗口.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>800</width>
    <height>200</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <property name="locale">
   <locale language="English" country="UnitedKingdom"/>
  </property>
  <widget class="QWidget" name="centralwidget">
   <layout class="QGridLayout" name="gridLayout_2">
    <item row="0" column="0">
     <layout class="QGridLayout" name="gridLayout">
      <item row="0" column="0">
       <widget class="QProgressBar" name="progressBar">
        <property name="value">
         <number>0</number>
        </property>
       </widget>
      </item>
      <item row="0" column="1">
       <widget class="QPushButton" name="pushButton">
        <property name="minimumSize">
         <size>
          <width>200</width>
          <height>0</height>
         </size>
        </property>
        <property name="styleSheet">
         <string notr="true">background-color: red;</string>
        </property>
        <property name="text">
         <string>Button</string>
        </property>
       </widget>
      </item>
     </layout>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menubar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>800</width>
     <height>28</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusbar"/>
 </widget>
 <resources/>
 <connections/>
</ui>

设置后 Raspbian Buster 上的终端输出

export QT_DEBUG_PLUGINS=1

：

QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqeglfs.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqeglfs.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "eglfs"
        ]
    },
    "className": "QEglFSIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("eglfs")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqlinuxfb.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqlinuxfb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "linuxfb"
        ]
    },
    "className": "QLinuxFbIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("linuxfb")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqminimal.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqminimal.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimal"
        ]
    },
    "className": "QMinimalIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("minimal")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqminimalegl.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqminimalegl.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "minimalegl"
        ]
    },
    "className": "QMinimalEglIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("minimalegl")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqoffscreen.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqoffscreen.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "offscreen"
        ]
    },
    "className": "QOffscreenIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("offscreen")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqvnc.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqvnc.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "vnc"
        ]
    },
    "className": "QVncIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("vnc")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqxcb.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqxcb.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
    "MetaData": {
        "Keys": [
            "xcb"
        ]
    },
    "className": "QXcbIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platforms" ...
loaded library "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforms/libqxcb.so"
loaded library "Xcursor"
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/xcbglintegrations" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/xcbglintegrations/libqxcb-egl-integration.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/xcbglintegrations/libqxcb-egl-integration.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.Xcb.QXcbGlIntegrationFactoryInterface.5.5",
    "MetaData": {
        "Keys": [
            "xcb_egl"
        ]
    },
    "className": "QXcbEglIntegrationPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("xcb_egl")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/xcbglintegrations" ...
loaded library "/usr/lib/arm-linux-gnueabihf/qt5/plugins/xcbglintegrations/libqxcb-egl-integration.so"
libEGL warning: DRI2: failed to authenticate
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqgtk2.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqgtk2.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformThemeFactoryInterface.5.1",
    "MetaData": {
        "Keys": [
            "gtk2"
        ]
    },
    "className": "QGtk2ThemePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("gtk2")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqgtk3.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqgtk3.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformThemeFactoryInterface.5.1",
    "MetaData": {
        "Keys": [
            "gtk3"
        ]
    },
    "className": "QGtk3ThemePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("gtk3")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqt5ct.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqt5ct.so, metadata=
{
    "IID": "org.qt-project.Qt.QPA.QPlatformThemeFactoryInterface.5.1",
    "MetaData": {
        "Keys": [
            "qt5ct"
        ]
    },
    "className": "Qt5CTPlatformThemePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("qt5ct")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platformthemes" ...
loaded library "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platformthemes/libqt5ct.so"
qt5ct: using qt5ct plugin
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libbb10styleplugin.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libbb10styleplugin.so, metadata=
{
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
        "Keys": [
            "bb10bright",
            "bb10dark"
        ]
    },
    "className": "QBB10StylePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("bb10bright", "bb10dark")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqcleanlooksstyle.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqcleanlooksstyle.so, metadata=
{
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
        "Keys": [
            "cleanlooks"
        ]
    },
    "className": "QCleanlooksStylePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("cleanlooks")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqgtk2style.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqgtk2style.so, metadata=
{
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
        "Keys": [
            "gtk2"
        ]
    },
    "className": "QGtk2StylePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("gtk2")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqmotifstyle.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqmotifstyle.so, metadata=
{
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
        "Keys": [
            "motif",
            "cde"
        ]
    },
    "className": "QMotifStylePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("motif", "cde")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqplastiquestyle.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqplastiquestyle.so, metadata=
{
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
        "Keys": [
            "plastique"
        ]
    },
    "className": "QPlastiqueStylePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("plastique")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqt5ct-style.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqt5ct-style.so, metadata=
{
    "IID": "org.qt-project.Qt.QStyleFactoryInterface",
    "MetaData": {
        "Keys": [
            "qt5ct-style"
        ]
    },
    "className": "Qt5CTStylePlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("qt5ct-style")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/styles" ...
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforminputcontexts" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforminputcontexts/libcomposeplatforminputcontextplugin.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforminputcontexts/libcomposeplatforminputcontextplugin.so, metadata=
{
    "IID": "org.qt-project.Qt.QPlatformInputContextFactoryInterface.5.1",
    "MetaData": {
        "Keys": [
            "compose",
            "xim"
        ]
    },
    "className": "QComposePlatformInputContextPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("compose", "xim")
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforminputcontexts/libibusplatforminputcontextplugin.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/platforminputcontexts/libibusplatforminputcontextplugin.so, metadata=
{
    "IID": "org.qt-project.Qt.QPlatformInputContextFactoryInterface.5.1",
    "MetaData": {
        "Keys": [
            "ibus"
        ]
    },
    "className": "QIbusPlatformInputContextPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("ibus")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platforminputcontexts" ...
loaded library "/usr/lib/arm-linux-gnueabihf/qt5/plugins/platforminputcontexts/libcomposeplatforminputcontextplugin.so"
loaded library "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqt5ct-style.so"
loaded library "/usr/lib/arm-linux-gnueabihf/qt5/plugins/styles/libqgtk2style.so"
Cannot load library gtk-x11-2.0: (gtk-x11-2.0: Kann die Shared-Object-Datei nicht öffnen: Datei oder Verzeichnis nicht gefunden)
qt5ct: D-Bus global menu: no
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/iconengines" ...
QFactoryLoader::QFactoryLoader() looking at "/usr/lib/arm-linux-gnueabihf/qt5/plugins/iconengines/libqsvgicon.so"
Found metadata in lib /usr/lib/arm-linux-gnueabihf/qt5/plugins/iconengines/libqsvgicon.so, metadata=
{
    "IID": "org.qt-project.Qt.QIconEngineFactoryInterface",
    "MetaData": {
        "Keys": [
            "svg",
            "svgz",
            "svg.gz"
        ]
    },
    "className": "QSvgIconPlugin",
    "debug": false,
    "version": 330499
}


Got keys from plugin meta data ("svg", "svgz", "svg.gz")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/iconengines" ...
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/accessible" ...
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/accessible" ...
QFactoryLoader::QFactoryLoader() checking directory path "/usr/lib/arm-linux-gnueabihf/qt5/plugins/accessiblebridge" ...
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/accessiblebridge" ...

Answer 1

我今天一直在解决类似的问题（这就是我找到你的帖子的方式）。要摆脱 libEGL 警告，请运行 raspi-config 并从“高级选项”->“GL 驱动程序”中选择“完整 KMS”选项（然后重新启动）。但这可能无法解决您的样式问题 - 我发现 Pi（我的目标系统）和我的 Linux Mint 开发系统之间存在样式差异。

Answer 2

我也有类似的问题，按照以下方式运行即可解决。

sudo python3.7 name.py

我猜想 IDE 或当前登录的用户需要一些权限。 尽管颜色仍然比 Windows 和 Ubuntu 中更不透明。

Answer 3

尝试使用这些命令：

应用程序 = QtWidgets.QApplication

app.setStyle(QStyleFactory.create('Cleanlooks'))

一定会成功的。