code: @Override
      void onPause() {
          super.onPause();
          mRotationSensor.onPause();
  
          if(NativeVulkanCore.getVulkanPropValue() > 0) {
              activeFlag = false;
  
              if (vulkanDrawThread != null){
                  try {
                      vulkanDrawThread.join();
                  } catch (InterruptedException e) {
                      Log.e("vulkan: activity onPause:", "draw thread not terminated");
                  }
              }
          }
          Log.d(TAG, "onPause");
      }
docs: Called when the system is about to start resuming a previous activity.
  This is typically used to commit unsaved changes to persistent data, stop
  animations and other things that may be consuming CPU, etc.
  Implementations of this method must be very quick because the next
  activity will not be resumed until this method returns.