GUI: Make window appear faster by running the 'populate tree' functio…

…n concurrently

CMakeLists.txt

@@ -266,9 +266,11 @@ find_package(Qt5Core REQUIRED)
 find_package(Qt5MultimediaWidgets REQUIRED)
 find_package(Qt5Widgets REQUIRED)
 find_package(Qt5Gui REQUIRED)
+find_package(Qt5Concurrent REQUIRED)
 include_directories(${Qt5Widgets_INCLUDE_DIRS})
 include_directories(${Qt5MultimediaWidgets_INCLUDE_DIRS})
-list(APPEND PHAETHON_LIBRARIES Qt5::Core Qt5::Widgets Qt5::MultimediaWidgets Qt5::Gui)
+include_directories(${Qt5Concurrent_INCLUDE_DIRS})
+list(APPEND PHAETHON_LIBRARIES Qt5::Core Qt5::Widgets Qt5::MultimediaWidgets Qt5::Gui Qt5::Concurrent)
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC")
 
 find_package(Iconv REQUIRED)

m4/ax_check_qt5.m4

@@ -11,7 +11,13 @@ dnl @version 2017-02-02
 dnl @license Creative Commons CC0 1.0 Universal Public Domain Dedication
 
 AC_DEFUN([AX_CHECK_QT5], [
-	PKG_CHECK_MODULES([QT5], [Qt5Core >= $1 Qt5Gui >= $1 Qt5Widgets >= $1 Qt5Multimedia >= $1], [$2], [$3])
+	PKG_CHECK_MODULES([QT5], [ \
+								Qt5Core >= $1 \
+								Qt5Gui >= $1 \
+								Qt5Widgets >= $1 \
+								Qt5Multimedia >= $1 \
+								Qt5Concurrent >= $1 \
+							  ], [$2], [$3])
 
 	# Qt5 needs -fPIC...
 	QT5_CFLAGS="$QT5_CFLAGS -fPIC"

src/gui/mainwindow.cpp

@@ -251,23 +251,7 @@ void MainWindow::slotLog(const QString &text) {
     _log->append(text);
 }
 
-void MainWindow::setTreeViewModel(const QString &path) {
-    if (_rootPath == path)
-        return;
-    _rootPath = path;
-
-    _status->push("Populating resource tree...");
-    BOOST_SCOPE_EXIT((&_status)) {
-        _status->pop();
-    } BOOST_SCOPE_EXIT_END
-
-    _treeView->setModel(nullptr);
-
-    if (_treeModel)
-        delete _treeModel;
-
-    _treeModel = new ResourceTree(this, path, _treeView);
-
+void MainWindow::finishTree() {
     if (_proxyModel)
         delete _proxyModel;
 
@@ -283,10 +267,28 @@ void MainWindow::setTreeViewModel(const QString &path) {
 
     _treeView->resizeColumnToContents(0);
 
-
     QObject::connect(_treeView->selectionModel(), &QItemSelectionModel::selectionChanged,
                      this, &MainWindow::resourceSelect);
 
+    _status->setText("Idle...");
+}
+
+void MainWindow::setTreeViewModel(const QString &path) {
+    if (_rootPath == path)
+        return;
+    _rootPath = path;
+
+    _status->push("Populating resource tree...");
+    BOOST_SCOPE_EXIT((&_status)) {
+        _status->pop();
+    } BOOST_SCOPE_EXIT_END
+
+    _treeView->setModel(nullptr);
+
+    if (_treeModel)
+        delete _treeModel;
+
+    _treeModel = new ResourceTree(this, path, _treeView);
 
     _log->append(tr("Set root: %1").arg(path));
 

src/gui/mainwindow.h

@@ -66,6 +66,7 @@ class MainWindow : public QMainWindow {
     ~MainWindow();
 
     std::shared_ptr<StatusBar> status();
+    void finishTree();
 
 private /*slots*/:
     void setTreeViewModel(const QString &path);

src/gui/resourcetree.cpp

@@ -23,6 +23,9 @@
  */
 
 #include <QDir>
+#include <QFuture>
+#include <QFutureWatcher>
+#include <QtConcurrentRun>
 #include <boost/scope_exit.hpp>
 
 #include "verdigris/wobjectimpl.h"
@@ -52,7 +55,7 @@ ResourceTree::ResourceTree(MainWindow *mainWindow, const QString &path, QObject
 
     _root = new ResourceTreeItem("Filename", nullptr);
 
-    _mainWindow->status()->push("Populating resource tree...");
+    _mainWindow->status()->setText("Populating resource tree...");
 
     ResourceTreeItem *top = _root;
 
@@ -63,9 +66,12 @@ ResourceTree::ResourceTree(MainWindow *mainWindow, const QString &path, QObject
         _root->appendChild(top);
     }
 
-    populate(path, top);
+    QFutureWatcher<void> *watcher = new QFutureWatcher<void>;
 
-    _mainWindow->status()->pop();
+    connect(watcher, &QFutureWatcher<void>::finished, _mainWindow, &MainWindow::finishTree);
+
+    QFuture<void> future = QtConcurrent::run(this, &ResourceTree::populate, path, top);
+    watcher->setFuture(future);
 }
 
 ResourceTree::~ResourceTree() {