Qt: Move library loading to a separate thread

src/platform/qt/ArchiveInspector.cpp

@@ -16,6 +16,9 @@ ArchiveInspector::ArchiveInspector(const QString& filename, QWidget* parent)
 	, m_model(ConfigController::configDir() + "/library.sqlite3")
 {
 	m_ui.setupUi(this);
+	connect(&m_model, &LibraryModel::doneLoading, [this]() {
+		m_ui.loading->hide();
+	});
 	m_model.loadDirectory(filename);
 	m_model.constrainBase(filename);
 	m_ui.archiveListing->setModel(&m_model);

src/platform/qt/ArchiveInspector.ui

@@ -14,14 +14,21 @@
    <string>Open in archive...</string>
   </property>
   <layout class="QGridLayout" name="gridLayout">
-   <item row="1" column="0">
+   <item row="2" column="1">
     <widget class="QDialogButtonBox" name="buttonBox">
      <property name="standardButtons">
       <set>QDialogButtonBox::Cancel|QDialogButtonBox::Open</set>
      </property>
     </widget>
    </item>
-   <item row="0" column="0">
+   <item row="2" column="0">
+    <widget class="QLabel" name="loading">
+     <property name="text">
+      <string>Loading...</string>
+     </property>
+    </widget>
+   </item>
+   <item row="0" column="0" colspan="2">
     <widget class="QListView" name="archiveListing"/>
    </item>
   </layout>

src/platform/qt/LibraryModel.cpp

@@ -21,17 +21,27 @@ LibraryModel::LibraryModel(const QString& path, QObject* parent)
 	}
 	memset(&m_constraints, 0, sizeof(m_constraints));
 	m_constraints.platform = PLATFORM_NONE;
+
+	if (!m_library) {
+		return;
+	}
+	m_loader = new LibraryLoader(m_library);
+	connect(m_loader, SIGNAL(directoryLoaded(const QString&)), this, SLOT(directoryLoaded(const QString&)));
+	m_loader->moveToThread(&m_loaderThread);
+	m_loaderThread.setObjectName("Library Loader Thread");
+	m_loaderThread.start();
 }
 
 LibraryModel::~LibraryModel() {
 	clearConstraints();
 	mLibraryDestroy(m_library);
+	m_loaderThread.quit();
+	m_loaderThread.wait();
 }
 
 void LibraryModel::loadDirectory(const QString& path) {
-	beginResetModel();
-	mLibraryLoadDirectory(m_library, path.toUtf8().constData());
-	endResetModel();
+	m_queue.append(path);
+	QMetaObject::invokeMethod(m_loader, "loadDirectory", Q_ARG(const QString&, path));
 }
 
 bool LibraryModel::entryAt(int row, mLibraryEntry* out) const {
@@ -136,3 +146,23 @@ void LibraryModel::clearConstraints() {
 	}
 	memset(&m_constraints, 0, sizeof(m_constraints));
 }
+
+void LibraryModel::directoryLoaded(const QString& path) {
+	m_queue.removeOne(path);
+	beginResetModel();
+	endResetModel();
+	if (m_queue.empty()) {
+		emit doneLoading();
+	}
+}
+
+LibraryLoader::LibraryLoader(mLibrary* library, QObject* parent)
+	: QObject(parent)
+	, m_library(library)
+{
+}
+
+void LibraryLoader::loadDirectory(const QString& path) {
+	mLibraryLoadDirectory(m_library, path.toUtf8().constData());
+	emit directoryLoaded(path);
+}

src/platform/qt/LibraryModel.h

@@ -7,6 +7,8 @@
 #define QGBA_LIBRARY_MODEL
 
 #include <QAbstractItemModel>
+#include <QStringList>
+#include <QThread>
 
 #include <mgba/core/library.h>
 
@@ -15,6 +17,7 @@ struct VFile;
 
 namespace QGBA {
 
+class LibraryLoader;
 class LibraryModel : public QAbstractItemModel {
 Q_OBJECT
 
@@ -22,8 +25,6 @@ public:
 	LibraryModel(const QString& path, QObject* parent = nullptr);
 	virtual ~LibraryModel();
 
-	void loadDirectory(const QString& path);
-
 	bool entryAt(int row, mLibraryEntry* out) const;
 	VFile* openVFile(const QModelIndex& index) const;
 
@@ -36,13 +37,40 @@ public:
 	virtual int columnCount(const QModelIndex& parent = QModelIndex()) const override;
 	virtual int rowCount(const QModelIndex& parent = QModelIndex()) const override;
 
+signals:
+	void doneLoading();
+
 public slots:
+	void loadDirectory(const QString& path);
+
 	void constrainBase(const QString& path);
 	void clearConstraints();
 
+private slots:
+	void directoryLoaded(const QString& path);
+
 private:
 	mLibrary* m_library;
 	mLibraryEntry m_constraints;
+	LibraryLoader* m_loader;
+	QThread m_loaderThread;
+	QStringList m_queue;
+};
+
+class LibraryLoader : public QObject {
+Q_OBJECT
+
+public:
+	LibraryLoader(mLibrary* library, QObject* parent = nullptr);
+
+public slots:
+	void loadDirectory(const QString& path);
+
+signals:
+	void directoryLoaded(const QString& path);
+
+private:
+	mLibrary* m_library;
 };
 
 }