Stop pitch detection when app is going background, restore when backs, Tsound...

Stop pitch detection when app is going background, restore when backs, Tsound - redirect isStopped of the sniffer.

changes

 1.???
+     - added notifications about too hi/low input volume
      - improved look of sound views, better fit to high DPI screens
     ANDROID
      - reduced paint operations, application works even 2-4 times faster
      - volume settings and pitch preview can be invoked with volume keys
+     - stop pitch detection when app is going background, restore when backs
     BUGS FIXES
      - other small fixes
 

src/libs/sound/tsound.cpp

@@ -275,6 +275,11 @@ bool Tsound::isSnifferPaused() {
 }
 
 
+bool Tsound::isSniferStopped() {
+  return sniffer ? sniffer->isStoped() : true;
+}
+
+
 void Tsound::restoreAfterAnswer() {
   m_pitchView->setBgColor(Qt::transparent);
   m_pitchView->setDisabled(true);

src/libs/sound/tsound.h

@@ -84,6 +84,7 @@ public:
   void pauseSinffing();
   void unPauseSniffing();
   bool isSnifferPaused();
+  bool isSniferStopped();
 
 			/** Prepares sound to exam.
 			 * Given notes in params are level range notes and are put to sniffer ambitus. */

src/mainwindow.cpp

@@ -82,10 +82,13 @@ void noteToKey(Tnote& n, TkeySignature k) {
       QNetworkAccessManager nam;
     }
 
-  TtouchMessage *m_touchMessage;
+  static TtouchMessage *m_touchMessage;
+  static bool m_isAppActive = true; /**< Whether Nootka is active (displayed) or suspended (and/or screen is off)  */
+  static bool m_wasPitchEnabled = false; /**< Stores state of pitch detection when Nootka becomes inactive screen is locked (off)  */
 #endif
 
 
+
 MainWindow::MainWindow(QWidget *parent) :
   QMainWindow(parent),
   m_examResults(0),
@@ -196,6 +199,24 @@ MainWindow::MainWindow(QWidget *parent) :
   connect(m_pitchView, &TpitchView::lowPCMvolume, this, &MainWindow::pcmStatusMessage);
   connect(m_pitchView, &TpitchView::hiPCMvolume, this, &MainWindow::pcmStatusMessage);
 
+#if defined (Q_OS_ANDROID)
+  connect(qApp, &QGuiApplication::applicationStateChanged, [=](Qt::ApplicationState state){
+      if (state == Qt::ApplicationActive) { // Nootka backs to live
+          if (!m_isAppActive) { // restore pitch detection state
+            if (m_wasPitchEnabled)
+              m_sound->go();
+            m_isAppActive = true;
+          }
+      } else { // Nootka goes to background
+          if (m_isAppActive) { // when it was active, store pitch detection state
+            m_wasPitchEnabled = !(m_sound->isSniferStopped() || m_sound->isSnifferPaused());
+            m_isAppActive = false;
+            m_sound->wait();
+          }
+      }
+  });
+#endif
+
   qApp->installEventFilter(this);
 }