Fixing the clock signal to use GLib::Dispatcher to emit the signal so the main thread updates the clockLabel widget

src/minefield.cpp

@@ -12,6 +12,10 @@ MineField::MineField(int cols, int rows, int mines): m_rows(rows),
   }
 }
 
+MineField::~MineField() {
+  //  stopTimer();
+}
+
 void MineField::timerTick() {
 
   auto start = std::chrono::system_clock::now();
@@ -35,7 +39,9 @@ void MineField::startTimer() {
 
 void MineField::stopTimer() {
   m_timerRunning = false;
-  m_timerThread.join();
+  if(m_timerThread.joinable()) {
+    m_timerThread.join();
+  }
 }
 
 void MineField::initBombs(int x, int y) {
@@ -63,7 +69,6 @@ void MineField::initBombs(int x, int y) {
 bool MineField::openCell(int x, int y) {
   if(isBomb(x, y)) {
     m_exploded = true;
-    timerThread.join();
     gameOverSignal.emit();
     stopTimer();
     return false;