DeviceManager: Show progress dialog while scanning for devices

We don't want users to wonder why nothing happens when they
start PV and no window shows up. Providing this dialog lets
them know that PV is starting and doing something.

diff --git a/pv/devicemanager.cpp b/pv/devicemanager.cpp
index a51148b1d3ad2851a55888749312cb12b837e523..58f507c92fae06c2cd2b84dfce474a5dfc5638de 100644 (file)
--- a/pv/devicemanager.cpp
+++ b/pv/devicemanager.cpp
@@ -22,12 +22,17 @@
 
 #include <cassert>
 #include <functional>
+#include <memory>
 #include <sstream>
 #include <stdexcept>
 #include <string>
 
 #include <libsigrokcxx/libsigrokcxx.hpp>
 
+#include <QApplication>
+#include <QObject>
+#include <QProgressDialog>
+
 #include <boost/filesystem.hpp>
 
 #include <pv/devices/hardwaredevice.hpp>
@@ -39,6 +44,7 @@ using std::placeholders::_1;
 using std::placeholders::_2;
 using std::shared_ptr;
 using std::string;
+using std::unique_ptr;
 
 using Glib::VariantBase;
 
@@ -51,8 +57,24 @@ namespace pv {
 DeviceManager::DeviceManager(shared_ptr<Context> context) :
        context_(context)
 {
-       for (auto entry : context->drivers())
+       unique_ptr<QProgressDialog> progress(new QProgressDialog("",
+               QObject::tr("Cancel"), 0, context->drivers().size()));
+       progress->setWindowModality(Qt::WindowModal);
+       progress->setMinimumDuration(1);  // To show the dialog immediately
+
+       int entry_num = 1;
+
+       for (auto entry : context->drivers()) {
+               progress->setLabelText(QObject::tr("Scanning for %1...")
+                       .arg(QString::fromStdString(entry.first)));
+
                driver_scan(entry.second, map<const ConfigKey *, VariantBase>());
+
+               progress->setValue(entry_num++);
+               QApplication::processEvents();
+               if (progress->wasCanceled())
+                       break;
+       }
 }
 
 const shared_ptr<sigrok::Context>& DeviceManager::context() const