lxqt-qtplugin-packaging/debian/patches/dynamically-load-file-dialog.patch

Description: Dynamically load libfm-qt
 Dynamically load libfm-qt on demand to create the file dialog helper to
 prevent the hard dependency on libfm-qt. This speed up the loading of the QPA
 plugin and also avoid loading libfm-qt in Qt programs having QT_NO_GLIB=1.
Author: Hong Jen Yee (PCMan) <pcman.tw@gmail.com>
Origin: upstream
Applied-Upstream: commit:334394a
Last-Update: 2018-07-30
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,10 +18,6 @@ find_package(Qt5XdgIconLoader REQUIRED)
 
 # Patch Version 0
 
-# for file dialog support
-find_package(Qt5X11Extras REQUIRED)
-find_package(fm-qt REQUIRED)
-
 include(LXQtPreventInSourceBuilds)
 include(LXQtCompilerSettings NO_POLICY_SCOPE)
 
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -6,7 +6,6 @@ include_directories(
 set(qtlxqt_HDRS
     lxqtplatformtheme.h
     lxqtsystemtrayicon.h
-    lxqtfiledialoghelper.h
     statusnotifieritem/statusnotifieritem.h
     statusnotifieritem/dbustypes.h
 )
@@ -15,7 +14,6 @@ set(qtlxqt_SRCS
     main.cpp
     lxqtplatformtheme.cpp
     lxqtsystemtrayicon.cpp
-    lxqtfiledialoghelper.cpp
     statusnotifieritem/statusnotifieritem.cpp
     statusnotifieritem/dbustypes.cpp
 )
@@ -38,7 +36,6 @@ target_link_libraries(qtlxqt
     Qt5::DBus
     dbusmenu-qt5
     Qt5XdgIconLoader
-    fm-qt
 )
 
 
--- a/src/lxqtfiledialoghelper.cpp
+++ /dev/null
@@ -1,276 +0,0 @@
-#include "lxqtfiledialoghelper.h"
-
-#include <libfm-qt/libfmqt.h>
-#include <libfm-qt/filedialog.h>
-
-#include <QWindow>
-#include <QDebug>
-#include <QTimer>
-#include <QSettings>
-
-#include <memory>
-
-static std::unique_ptr<Fm::LibFmQt> libfmQtContext_;
-
-inline static const QString viewModeToString(Fm::FolderView::ViewMode value);
-inline static Fm::FolderView::ViewMode viewModeFromString(const QString& str);
-
-LXQtFileDialogHelper::LXQtFileDialogHelper() {
-    if(!libfmQtContext_) {
-        // initialize libfm-qt only once
-        libfmQtContext_ = std::unique_ptr<Fm::LibFmQt>{new Fm::LibFmQt()};
-    }
-
-    // can only be used after libfm-qt initialization
-    dlg_ = std::unique_ptr<Fm::FileDialog>(new Fm::FileDialog());
-    connect(dlg_.get(), &Fm::FileDialog::accepted, [this]() {
-        saveSettings();
-        accept();
-    });
-    connect(dlg_.get(), &Fm::FileDialog::rejected, [this]() {
-        saveSettings();
-        reject();
-    });
-
-    connect(dlg_.get(), &Fm::FileDialog::fileSelected, this, &LXQtFileDialogHelper::fileSelected);
-    connect(dlg_.get(), &Fm::FileDialog::filesSelected, this, &LXQtFileDialogHelper::filesSelected);
-    connect(dlg_.get(), &Fm::FileDialog::currentChanged, this, &LXQtFileDialogHelper::currentChanged);
-    connect(dlg_.get(), &Fm::FileDialog::directoryEntered, this, &LXQtFileDialogHelper::directoryEntered);
-    connect(dlg_.get(), &Fm::FileDialog::filterSelected, this, &LXQtFileDialogHelper::filterSelected);
-}
-
-LXQtFileDialogHelper::~LXQtFileDialogHelper() {
-}
-
-void LXQtFileDialogHelper::exec() {
-    dlg_->exec();
-}
-
-bool LXQtFileDialogHelper::show(Qt::WindowFlags windowFlags, Qt::WindowModality windowModality, QWindow* parent) {
-    dlg_->setAttribute(Qt::WA_NativeWindow, true); // without this, sometimes windowHandle() will return nullptr
-
-    dlg_->setWindowFlags(windowFlags);
-    dlg_->setWindowModality(windowModality);
-
-    // Reference: KDE implementation
-    // https://github.com/KDE/plasma-integration/blob/master/src/platformtheme/kdeplatformfiledialoghelper.cpp
-    dlg_->windowHandle()->setTransientParent(parent);
-
-    applyOptions();
-
-    loadSettings();
-    // central positioning with respect to the parent window
-    if(parent && parent->isVisible()) {
-        dlg_->move(parent->x() + (parent->width() - dlg_->width()) / 2,
-                   parent->y() + (parent->height() - dlg_->height()) / 2);
-    }
-
-    // NOTE: the timer here is required as a workaround borrowed from KDE. Without this, the dialog UI will be blocked.
-    // QFileDialog calls our platform plugin to show our own native file dialog instead of showing its widget.
-    // However, it still creates a hidden dialog internally, and then make it modal.
-    // So user input from all other windows that are not the children of the QFileDialog widget will be blocked.
-    // This includes our own dialog. After the return of this show() method, QFileDialog creates its own window and
-    // then make it modal, which blocks our UI. The timer schedule a delayed popup of our file dialog, so we can
-    // show again after QFileDialog and override the modal state. Then our UI can be unblocked.
-    QTimer::singleShot(0, dlg_.get(), &QDialog::show);
-    dlg_->setFocus();
-    return true;
-}
-
-void LXQtFileDialogHelper::hide() {
-    dlg_->hide();
-}
-
-bool LXQtFileDialogHelper::defaultNameFilterDisables() const {
-    return false;
-}
-
-void LXQtFileDialogHelper::setDirectory(const QUrl& directory) {
-    dlg_->setDirectory(directory);
-}
-
-QUrl LXQtFileDialogHelper::directory() const {
-    return dlg_->directory();
-}
-
-void LXQtFileDialogHelper::selectFile(const QUrl& filename) {
-    dlg_->selectFile(filename);
-}
-
-QList<QUrl> LXQtFileDialogHelper::selectedFiles() const {
-    return dlg_->selectedFiles();
-}
-
-void LXQtFileDialogHelper::setFilter() {
-    // FIXME: what's this?
-    // The gtk+ 3 file dialog helper in Qt5 update options in this method.
-    applyOptions();
-}
-
-void LXQtFileDialogHelper::selectNameFilter(const QString& filter) {
-    dlg_->selectNameFilter(filter);
-}
-
-#if QT_VERSION >= QT_VERSION_CHECK(5, 9, 0)
-QString LXQtFileDialogHelper::selectedMimeTypeFilter() const {
-    return dlg_->selectedMimeTypeFilter();
-}
-
-void LXQtFileDialogHelper::selectMimeTypeFilter(const QString& filter) {
-    dlg_->selectMimeTypeFilter(filter);
-}
-#endif
-
-QString LXQtFileDialogHelper::selectedNameFilter() const {
-    return dlg_->selectedNameFilter();
-}
-
-bool LXQtFileDialogHelper::isSupportedUrl(const QUrl& url) const {
-    return dlg_->isSupportedUrl(url);
-}
-
-void LXQtFileDialogHelper::applyOptions() {
-    auto& opt = options();
-
-    // set title
-    if(opt->windowTitle().isEmpty()) {
-        dlg_->setWindowTitle(opt->acceptMode() == QFileDialogOptions::AcceptOpen ? tr("Open File")
-                                                                                 : tr("Save File"));
-    }
-    else {
-        dlg_->setWindowTitle(opt->windowTitle());
-    }
-
-    dlg_->setFilter(opt->filter());
-    dlg_->setFileMode(QFileDialog::FileMode(opt->fileMode()));
-    dlg_->setAcceptMode(QFileDialog::AcceptMode(opt->acceptMode())); // also sets a default label for accept button
-    // bool useDefaultNameFilters() const;
-    dlg_->setNameFilters(opt->nameFilters());
-    if(!opt->mimeTypeFilters().empty()) {
-        dlg_->setMimeTypeFilters(opt->mimeTypeFilters());
-    }
-
-    dlg_->setDefaultSuffix(opt->defaultSuffix());
-    // QStringList history() const;
-
-    // explicitly set labels
-    for(int i = 0; i < QFileDialogOptions::DialogLabelCount; ++i) {
-        auto label = static_cast<QFileDialogOptions::DialogLabel>(i);
-        if(opt->isLabelExplicitlySet(label)) {
-            dlg_->setLabelText(static_cast<QFileDialog::DialogLabel>(label), opt->labelText(label));
-        }
-    }
-
-    auto url = opt->initialDirectory();
-    if(url.isValid()) {
-        dlg_->setDirectory(url);
-    }
-
-
-#if QT_VERSION >= QT_VERSION_CHECK(5, 9, 0)
-    auto filter = opt->initiallySelectedMimeTypeFilter();
-    if(!filter.isEmpty()) {
-        selectMimeTypeFilter(filter);
-    }
-    else {
-        filter = opt->initiallySelectedNameFilter();
-        if(!filter.isEmpty()) {
-            selectNameFilter(opt->initiallySelectedNameFilter());
-        }
-    }
-#else
-    auto filter = opt->initiallySelectedNameFilter();
-    if(!filter.isEmpty()) {
-        selectNameFilter(filter);
-    }
-#endif
-
-    auto selectedFiles = opt->initiallySelectedFiles();
-    for(const auto& selectedFile: selectedFiles) {
-        selectFile(selectedFile);
-    }
-    // QStringList supportedSchemes() const;
-}
-
-static const QString viewModeToString(Fm::FolderView::ViewMode value) {
-    QString ret;
-    switch(value) {
-    case Fm::FolderView::DetailedListMode:
-    default:
-        ret = QLatin1String("Detailed");
-        break;
-    case Fm::FolderView::CompactMode:
-        ret = QLatin1String("Compact");
-        break;
-    case Fm::FolderView::IconMode:
-        ret = QLatin1String("Icon");
-        break;
-    case Fm::FolderView::ThumbnailMode:
-        ret = QLatin1String("Thumbnail");
-        break;
-    }
-    return ret;
-}
-
-Fm::FolderView::ViewMode viewModeFromString(const QString& str) {
-    Fm::FolderView::ViewMode ret;
-    if(str == QLatin1String("Detailed")) {
-        ret = Fm::FolderView::DetailedListMode;
-    }
-    else if(str == QLatin1String("Compact")) {
-        ret = Fm::FolderView::CompactMode;
-    }
-    else if(str == QLatin1String("Icon")) {
-        ret = Fm::FolderView::IconMode;
-    }
-    else if(str == QLatin1String("Thumbnail")) {
-        ret = Fm::FolderView::ThumbnailMode;
-    }
-    else {
-        ret = Fm::FolderView::DetailedListMode;
-    }
-    return ret;
-}
-
-void LXQtFileDialogHelper::loadSettings() {
-    QSettings settings(QSettings::UserScope, "lxqt", "filedialog");
-    settings.beginGroup ("Sizes");
-    dlg_->resize(settings.value("WindowSize", QSize(700, 500)).toSize());
-    dlg_->setSplitterPos(settings.value("SplitterPos", 200).toInt());
-    settings.endGroup();
-
-   settings.beginGroup ("View");
-   dlg_->setViewMode(viewModeFromString(settings.value("Mode", "Detailed").toString()));
-   settings.endGroup();
-}
-
-void LXQtFileDialogHelper::saveSettings() {
-    QSettings settings(QSettings::UserScope, "lxqt", "filedialog");
-    settings.beginGroup ("Sizes");
-    QSize windowSize = dlg_->size();
-    if(settings.value("WindowSize") != windowSize) { // no redundant write
-        settings.setValue("WindowSize", windowSize);
-    }
-    int splitterPos = dlg_->splitterPos();
-    if(settings.value("SplitterPos") != splitterPos) {
-        settings.setValue("SplitterPos", splitterPos);
-    }
-    settings.endGroup();
-
-    settings.beginGroup ("View");
-    QString mode = viewModeToString(dlg_->viewMode());
-    if(settings.value("Mode") != mode) {
-        settings.setValue("Mode", mode);
-    }
-    settings.endGroup();
-}
-
-/*
-FileDialogPlugin::FileDialogPlugin() {
-
-}
-
-QPlatformFileDialogHelper *FileDialogPlugin::createHelper() {
-    return new LXQtFileDialogHelper();
-}
-*/
--- a/src/lxqtfiledialoghelper.h
+++ /dev/null
@@ -1,50 +0,0 @@
-#ifndef LXQTFILEDIALOGHELPER_H
-#define LXQTFILEDIALOGHELPER_H
-
-#include <qpa/qplatformdialoghelper.h> // this private header is subject to changes
-#include <memory>
-
-namespace Fm {
-class FileDialog;
-}
-
-class Q_GUI_EXPORT LXQtFileDialogHelper : public QPlatformFileDialogHelper {
-    Q_OBJECT
-
-public:
-    LXQtFileDialogHelper();
-
-    virtual ~LXQtFileDialogHelper();
-
-    // QPlatformDialogHelper
-    void exec() override;
-    bool show(Qt::WindowFlags windowFlags, Qt::WindowModality windowModality, QWindow *parent) override;
-    void hide() override;
-
-    // QPlatformFileDialogHelper
-    bool defaultNameFilterDisables() const override;
-    void setDirectory(const QUrl &directory) override;
-    QUrl directory() const override;
-    void selectFile(const QUrl &filename) override;
-    QList<QUrl> selectedFiles() const override;
-    void setFilter() override;
-    void selectNameFilter(const QString &filter) override;
-#if QT_VERSION >= QT_VERSION_CHECK(5, 9, 0)
-    QString selectedMimeTypeFilter() const override;
-    void selectMimeTypeFilter(const QString &filter) override;
-#endif
-    QString selectedNameFilter() const override;
-
-    bool isSupportedUrl(const QUrl &url) const override;
-
-private:
-    void applyOptions();
-    void loadSettings();
-    void saveSettings();
-
-private:
-    std::unique_ptr<Fm::FileDialog> dlg_;
-};
-
-
-#endif // LXQTFILEDIALOGHELPER_H
--- a/src/lxqtplatformtheme.cpp
+++ b/src/lxqtplatformtheme.cpp
@@ -45,8 +45,14 @@
 #include <QFileSystemWatcher>
 #include <QStyle>
 #include <private/xdgiconloader/xdgiconloader_p.h>
+#include <QLibrary>
+
+
+// Function to create a new Fm::FileDialogHelper object.
+// This is dynamically loaded at runtime on demand from libfm-qt.
+typedef QPlatformDialogHelper* (*CreateFileDialogHelperFunc)();
+static CreateFileDialogHelperFunc createFileDialogHelper = nullptr;
 
-#include "lxqtfiledialoghelper.h"
 
 LXQtPlatformTheme::LXQtPlatformTheme():
     iconFollowColorScheme_(true)
@@ -222,8 +228,32 @@ bool LXQtPlatformTheme::usePlatformNativ
 QPlatformDialogHelper *LXQtPlatformTheme::createPlatformDialogHelper(DialogType type) const {
     if(type == FileDialog
        && qobject_cast<QApplication *>(QCoreApplication::instance())) { // QML may not have qApp
-        // use our own file dialog
-        return new LXQtFileDialogHelper();
+        // use our own file dialog provided by libfm
+
+        // When a process has this environment set, that means glib event loop integration is disabled.
+        // In this case, libfm-qt just won't work. So let's disable the file dialog helper and return nullptr.
+        if(qgetenv("QT_NO_GLIB") == "1") {
+            return nullptr;
+        }
+
+        // The createFileDialogHelper() method is dynamically loaded from libfm-qt on demand
+        if(createFileDialogHelper == nullptr) {
+            // try to dynamically load libfm-qt.so
+            QLibrary libfmQtLibrary{"libfm-qt"};
+            libfmQtLibrary.load();
+            if(!libfmQtLibrary.isLoaded()) {
+                return nullptr;
+            }
+
+            // try to resolve the symbol to get the function pointer
+            createFileDialogHelper = reinterpret_cast<CreateFileDialogHelperFunc>(libfmQtLibrary.resolve("createFileDialogHelper"));
+            if(!createFileDialogHelper) {
+                return nullptr;
+            }
+        }
+
+        // create a new file dialog helper provided by libfm
+        return createFileDialogHelper();
     }
     return nullptr;
 }