Allows restarting of crashed persistent apps

main.py

@@ -95,14 +95,11 @@ if config.UseGui:
                     self.cv.wait()
                     data = self.datasource.getData()
                 screen.fill((0, 255, 0))
-                try:
                 for x in range(config.ScreenX):
                     for y in range(config.ScreenY):
                         i = x+y*config.ScreenX
                         color = (data[i*3+0], data[i*3+1], data[i*3+2])
                         pygame.draw.rect(screen, color, pygame.Rect(sf*x, sf*y, sf, sf))
-                except:
-                    raise
                 pygame.display.flip()
             logging.info("Closing GUI")
         def join(self):
@@ -257,7 +254,8 @@ class AppRunner(threading.Thread):
         if self.app != None and not self.app.is_persistent:
             self.app.stop()
         self.currentApp = self.requestedApp
-        if self.currentApp in self.persistent_apps.keys():
+        if (self.currentApp in self.persistent_apps.keys() 
+            and self.persistent_apps[self.currentApp].alive()):
             self.app = self.persistent_apps[self.currentApp]
         else:
             self.app = self.startApp(self.requestedApp, self.param)