Fix issue with list of metrics in CustomDataset.evaluate (open-mmlab#…

…2128)

* Fix issue with list of metrics in CustomDataset.evaluate

Changes to be committed:
modified:   mmdet/datasets/custom.py

* Updated to evaluate only one of mAP or recall

Changes to be committed:
modified:   mmdet/datasets/custom.py

mmdet/datasets/custom.py

@@ -178,6 +178,9 @@ def evaluate(self,
             scale_ranges (list[tuple] | None): Scale ranges for evaluating mAP.
                 Default: None.
         """
+        if not isinstance(metric, str):
+            assert len(metric) == 1
+            metric = metric[0]
         allowed_metrics = ['mAP', 'recall']
         if metric not in allowed_metrics:
             raise KeyError('metric {} is not supported'.format(metric))
@@ -198,11 +201,7 @@ def evaluate(self,
             if isinstance(iou_thr, float):
                 iou_thr = [iou_thr]
             recalls = eval_recalls(
-                gt_bboxes,
-                results,
-                proposal_nums,
-                iou_thr,
-                print_summary=False)
+                gt_bboxes, results, proposal_nums, iou_thr, logger=logger)
             for i, num in enumerate(proposal_nums):
                 for j, iou in enumerate(iou_thr):
                     eval_results['recall@{}@{}'.format(num, iou)] = recalls[i,