亚克力效果覆盖到其它 linux 桌面的探究

[yanhuacuo]

FluTools.cpp 中有个函数，定义了找查当前壁纸的方法：

QString FluTools::getWallpaperFilePath() {
#if defined(Q_OS_WIN)
    wchar_t path[MAX_PATH] = {};
    if (::SystemParametersInfoW(SPI_GETDESKWALLPAPER, MAX_PATH, path, FALSE) == FALSE) {
        return {};
    }
    return QString::fromWCharArray(path);
#elif defined(Q_OS_LINUX)
    auto type = QSysInfo::productType();
    if (type == "uos") {
        QProcess process;
        QStringList args;
        args << "--session";
        args << "--type=method_call";
        args << "--print-reply";
        args << "--dest=com.deepin.wm";
        args << "/com/deepin/wm";
        args << "com.deepin.wm.GetCurrentWorkspaceBackgroundForMonitor";
        args << QString("string:'%1'").arg(currentTimestamp());
        process.start("dbus-send", args);
        process.waitForFinished();
        QByteArray result = process.readAllStandardOutput().trimmed();
        int startIndex = result.indexOf("file:///");
        if (startIndex != -1) {
            auto path = result.mid(startIndex + 7, result.length() - startIndex - 8);
            return path;
        }
    }
#elif defined(Q_OS_MACOS)
    QProcess process;
    QStringList args;
    args << "-e";
    args << R"(tell application "Finder" to get POSIX path of (desktop picture as alias))";
    process.start("osascript", args);
    process.waitForFinished();
    QByteArray result = process.readAllStandardOutput().trimmed();
    if(result.isEmpty()){
        return "/System/Library/CoreServices/DefaultDesktop.heic";
    }
    return result;
#else
    return {};
#endif
}

群主使用 auto type = QSysInfo::productType(); 来实现大概的系统判断，但这个确实有很大的局限性。目前 FluApp 的这一特性因此无法覆盖到其它比较流行的桌面环境，比如 Gnome 或 KDE

在 Qt 下，可以调用 bash 执行一个本地变量读取操作，获取到当前用户正在使用的桌面环境名称，比如拟用 QString FluTools::getCurrentDesktopName() ，会得到 Gnome 或 KDE 等等。

QString FluTools::getCurrentDesktopName(){
    QProcess process;  
    QString program = "bash";
    QStringList arguments;  
    arguments << "-c" << "echo $XDG_CURRENT_DESKTOP";
    process.start(program, arguments);
    process.waitForFinished();

    QByteArray output = process.readAllStandardOutput();  
    QString desktopEnvironment = QString::fromLocal8Bit(output);
    desktopEnvironment = desktopEnvironment.trimmed()
    qDebug() << "Desktop Environment:" << desktopEnvironment << '\n';

    return desktopEnvironment;
}

[yanhuacuo]

其实 Linux 下的桌面环境，主流也就两三种。再根据它们的特性，特别写一下获取方式，应该是可以的。

[yanhuacuo]

以我当前使用的 KDE 桌面环境为例，它「时时记录」当前壁纸路径完整信息的文件是：

/home/i5/.config/plasma-org.kde.plasma.desktop-appletsrc

这里，plasma-org.kde.plasma.desktop-appletsrc 是一个固定的系统文件，在它的字段下：

即使用户设置了「每一秒换一次壁纸」，KDE桌面也是先将实际的图片地址写到这里，再下发到桌面其它组件来渲染：

比如，我们看到这一时刻，生效的壁纸是：file:///home/i5/图片/图片/Ducks on a Misty Pond.jpg

那么，写一个 KDE 下读取该字段的函数，就是非常简单的了：

[Containments][1][Wallpaper][org.kde.slideshow][General]
Image=file:///home/i5/图片/图片/Ducks on a Misty Pond.jpg
SlideInterval=10
SlidePaths=/home/i5/图片/图片/
SlideshowFoldersFirst=true
SlideshowMode=1

[yanhuacuo]

同样地，Gnome 桌面环境中，可以直接使用 bash 如法泡制：

https://unix.stackexchange.com/questions/606635/how-to-find-current-wallpaper-image-file-path

https://askubuntu.com/questions/1220766/how-to-get-the-file-location-of-the-current-wallpaper-file

gsettings get org.cinnamon.desktop.background picture-uri

[yanhuacuo]

KDE 与 Gnome 兼容进来，就解决了 99% 的linux桌面用户，其它小众桌面环境，几乎可以忽略不计。

[yanhuacuo]

趁楚哥正在制作新版，给一点建议，希望能有助益。

[yanhuacuo]

适配 Gnome 与 KDE 的办法，已测可行：

QString FluTools::getWallpaperFilePath() {
#if defined(Q_OS_WIN)
    wchar_t path[MAX_PATH] = {};
    if (::SystemParametersInfoW(SPI_GETDESKWALLPAPER, MAX_PATH, path, FALSE) == FALSE) {
        return {};
    }
    return QString::fromWCharArray(path);
#elif defined(Q_OS_LINUX)
    QString currentDesktopName = getCurrentDesktopName();

    if(currentDesktopName.contains("KDE")){
        QString str = getKDEWallpaperFilePath();
        qDebug() << "KDE_WallpaperFilePath :" << str  << '\n';
        return str;
    }

    if(currentDesktopName.contains("GNOME")){
        QString str = getGnomeWallpaperFilePath();
        qDebug() << "Gnome_WallpaperFilePath :" << str  << '\n';
        return str;
    }

    auto type = QSysInfo::productType();
    if (type == "uos") {
        QProcess process;
        QStringList args;
        args << "--session";
        args << "--type=method_call";
        args << "--print-reply";
        args << "--dest=com.deepin.wm";
        args << "/com/deepin/wm";
        args << "com.deepin.wm.GetCurrentWorkspaceBackgroundForMonitor";
        args << QString("string:'%1'").arg(currentTimestamp());
        process.start("dbus-send", args);
        process.waitForFinished();
        QByteArray result = process.readAllStandardOutput().trimmed();
        int startIndex = result.indexOf("file:///");
        if (startIndex != -1) {
            auto path = result.mid(startIndex + 7, result.length() - startIndex - 8);
            return path;
        }
    }
#elif defined(Q_OS_MACOS)
    QProcess process;
    QStringList args;
    args << "-e";
    args << R"(tell application "Finder" to get POSIX path of (desktop picture as alias))";
    process.start("osascript", args);
    process.waitForFinished();
    QByteArray result = process.readAllStandardOutput().trimmed();
    if(result.isEmpty()){
        return "/System/Library/CoreServices/DefaultDesktop.heic";
    }
    return result;
#else
    return {};
#endif
    return {};
}


QString FluTools::getCurrentUserName(){
    QProcess process;
    process.start("whoami");
    process.waitForFinished();

    QString output = process.readAllStandardOutput();
    output.remove(QChar('\n')); // 移除换行符（如果有的话）

    return output;
}

QString FluTools::getCurrentDesktopName(){

    QProcess process;
    QString program = "bash";
    QStringList arguments;
    arguments << "-c" << "echo $XDG_CURRENT_DESKTOP";
    process.start(program, arguments);
    process.waitForFinished();

    QByteArray output = process.readAllStandardOutput();
    QString desktopEnvironment = QString::fromLocal8Bit(output);
    desktopEnvironment = desktopEnvironment.trimmed();
    qDebug() << "Desktop Environment:" << desktopEnvironment << '\n';

    return desktopEnvironment;

}

QString FluTools::getKDEWallpaperFilePath(){

    QString currentUserName = getCurrentUserName();
    QString currentLogPath = QString("/home/%1/.config/plasma-org.kde.plasma.desktop-appletsrc").arg(currentUserName);
    QFile aFile(currentLogPath);
    if(!aFile.exists()){
        qDebug() << "This KDE file is not exits !" << currentLogPath << '\n';
        return NULL;
    }
    if(!aFile.open(QIODevice::ReadOnly|QIODevice::Text)){
        qDebug() << "This KDE file open failed !" << currentLogPath << '\n';
        return NULL;
    }
    QTextStream aStream(&aFile);
    aStream.setAutoDetectUnicode(true);

    bool arrivedTarget = false;
    QString str;

    while(!aStream.atEnd()){
        str = aStream.readLine();
        if(str.contains("[Wallpaper]")){
             arrivedTarget = true;
        }
        if(str.contains("Image=file://")){
            if(arrivedTarget){
                QString strTemp = str;
                strTemp.replace("Image=file://","");
                qDebug() << "current KDEWallpaper is: " << strTemp << '\n';
                return strTemp;
            }
        }
    }
    return NULL;
}

QString FluTools::getGnomeWallpaperFilePath(){
    QProcess process;
    QString program = "bash";
    QStringList arguments;
    arguments << "-c" << "gsettings get org.gnome.desktop.background picture-uri";
    process.start(program, arguments);
    process.waitForFinished();
    QByteArray output = process.readAllStandardOutput();
    QString filePath = QString::fromLocal8Bit(output);
    filePath = filePath.trimmed();
    filePath.replace("file://","");
    qDebug() << "current GnomeWallpaper is: " << filePath << '\n';
    return filePath;
}