Merge pull request #50 from jbellister-slac/filter_segfault

FIX: Prevent segfaults when filtering the alarm table

slam/alarm_table_model.py

@@ -89,19 +89,17 @@ def append(self, alarm_item: AlarmItem) -> None:
         if alarm_item.name in self.alarm_items:
             logger.warning(f'Attempting to append a row to the alarm table which is already there: {alarm_item.name}')
             return
-        self.beginInsertRows(QModelIndex(), len(self.alarm_items), len(self.alarm_items))
+        self.layoutAboutToBeChanged.emit()
         self.alarm_items[alarm_item.name] = alarm_item
-        self.endInsertRows()
         self.layoutChanged.emit()
 
     def remove_row(self, alarm_name: str):
         """ Removes the row associated with the input name from this table """
         if alarm_name not in self.alarm_items:
             return
         index_to_remove = list(self.alarm_items.keys()).index(alarm_name)
-        self.beginRemoveRows(QModelIndex(), index_to_remove, index_to_remove)
+        self.layoutAboutToBeChanged.emit()
         del self.alarm_items[alarm_name]
-        self.endRemoveRows()
         self.layoutChanged.emit()
 
     def sort(self, col: int, order=Qt.AscendingOrder):

slam/alarm_table_view.py

@@ -3,11 +3,11 @@
 import socket
 from functools import partial
 from kafka.producer import KafkaProducer
-from qtpy.QtCore import QEvent, QSortFilterProxyModel, Qt, Signal
+from qtpy.QtCore import QEvent, QModelIndex, QSortFilterProxyModel, Qt, Signal
 from qtpy.QtGui import QCursor
 from qtpy.QtWidgets import (QAbstractItemView, QAction, QApplication, QHBoxLayout, QHeaderView, QLabel,
                             QLineEdit, QMenu, QPushButton, QTableView, QVBoxLayout, QWidget)
-from typing import Callable
+from typing import Callable, List
 from .alarm_table_model import AlarmItemsTableModel
 from .alarm_tree_model import AlarmItemsTreeModel
 from .permissions import UserAction, can_take_action
@@ -122,8 +122,7 @@ def __init__(self, tree_model: AlarmItemsTreeModel, kafka_producer: KafkaProduce
         self.layout.addWidget(self.filter_active_label)
         self.layout.addWidget(self.alarmView)
 
-        self.alarmModel.rowsInserted.connect(self.update_counter_label)
-        self.alarmModel.rowsRemoved.connect(self.update_counter_label)
+        self.alarmModel.layoutChanged.connect(self.update_counter_label)
 
     def filter_table(self) -> None:
         """ Filter the table based on the text typed into the filter bar """
@@ -150,17 +149,24 @@ def alarm_context_menu_event(self, ev: QEvent) -> None:
         """ Display the right-click context menu for items in the active alarms table """
         self.alarm_context_menu.popup(QCursor.pos())
 
+    def get_selected_indices(self) -> List[QModelIndex]:
+        """ Return the indices which have been selected by the user, applying a mapping if a filter has been applied """
+        indices = self.alarmView.selectionModel().selectedRows()
+        if self.filter_active_label.isVisible():
+            indices = [self.alarm_proxy_model.mapToSource(proxy_index) for proxy_index in indices]
+        return indices
+
     def plot_pv(self) -> None:
         """ Send off the signal for plotting a PV """
-        indices = self.alarmView.selectedIndexes()
+        indices = self.get_selected_indices()
         if len(indices) > 0:
             index = indices[0]
             alarm_item = list(self.alarmModel.alarm_items.items())[index.row()][1]
             self.plot_signal.emit(alarm_item.name)
 
     def copy_alarm_name_to_clipboard(self) -> None:
         """ Copy the selected PV to the user's clipboard """
-        indices = self.alarmView.selectionModel().selectedRows()
+        indices = self.get_selected_indices()
         if len(indices) > 0:
             copy_text = ''
             for index in indices:
@@ -174,7 +180,7 @@ def send_acknowledge_action(self, acknowledged: bool) -> None:
         if not can_take_action(UserAction.ACKNOWLEDGE, log_warning=True):
             return
 
-        indices = self.alarmView.selectionModel().selectedRows()
+        indices = self.get_selected_indices()
         if len(indices) > 0:
             for index in indices:
                 alarm_item = list(self.alarmModel.alarm_items.items())[index.row()][1]
@@ -191,4 +197,4 @@ def send_acknowledge_action(self, acknowledged: bool) -> None:
                         self.kafka_producer.send(self.topic + 'Command',
                                                  key=f'command:{alarm_path}',
                                                  value={'user': username, 'host': hostname, 'command': command_to_send})
-
+        self.alarmView.selectionModel().reset()