修复报错

backend/SystemUpdater/backend/__init__.py

@@ -17,7 +17,6 @@ from SystemUpdater.Core.utils import (
 )
 from aptdaemon.enums import get_status_string_from_enum
 from ..Core.Database import MODE_DEFAULT_STATUS,MODE_UPGRADE_PARTIAL,MODE_UPGRADE_ALL,MODE_UPGRADE_SYSTEM,MODE_UPGRADE_SINGLE
-from .InstallBackendAptdaemon import InstallBackendAptdaemon
 
 class NowUpgradePara:
     """
@@ -345,6 +344,14 @@ class InstallBackend():
             pass
             unLockedEnableShutdown()
 
+# try aptdaemon
+if os.path.exists("/usr/sbin/aptd") \
+   and "UPDATE_MANAGER_FORCE_BACKEND_SYNAPTIC" not in os.environ:
+    # check if the gtkwidgets are installed as well
+    try:
+        from .InstallBackendAptdaemon import InstallBackendAptdaemon
+    except ImportError:
+        logging.exception("importing aptdaemon")
 
 def get_backend(*args, **kwargs):
     """Select and return a package manager backend."""