prevent exception if user presses delete key when no more messages to delete

bitmessagemain.py

@@ -5021,31 +5021,33 @@ class MyForm(QtGui.QMainWindow):
     #Send item on the Inbox tab to trash
     def on_action_InboxTrash(self):
         currentRow = self.ui.tableWidgetInbox.currentRow()
-        inventoryHashToTrash = str(self.ui.tableWidgetInbox.item(currentRow,3).data(Qt.UserRole).toPyObject())
-        t = (inventoryHashToTrash,)
-        sqlLock.acquire()
-        #sqlSubmitQueue.put('''delete from inbox where msgid=?''')
-        sqlSubmitQueue.put('''UPDATE inbox SET folder='trash' WHERE msgid=?''')
-        sqlSubmitQueue.put(t)
-        sqlReturnQueue.get()
-        sqlLock.release()
-        self.ui.textEditInboxMessage.setText("")
-        self.ui.tableWidgetInbox.removeRow(currentRow)
-        self.statusBar().showMessage('Moved item to trash. There is no user interface to view your trash, but it is still on disk if you are desperate to get it back.')
+        if currentRow >= 0:
+            inventoryHashToTrash = str(self.ui.tableWidgetInbox.item(currentRow,3).data(Qt.UserRole).toPyObject())
+            t = (inventoryHashToTrash,)
+            sqlLock.acquire()
+            #sqlSubmitQueue.put('''delete from inbox where msgid=?''')
+            sqlSubmitQueue.put('''UPDATE inbox SET folder='trash' WHERE msgid=?''')
+            sqlSubmitQueue.put(t)
+            sqlReturnQueue.get()
+            sqlLock.release()
+            self.ui.textEditInboxMessage.setText("")
+            self.ui.tableWidgetInbox.removeRow(currentRow)
+            self.statusBar().showMessage('Moved item to trash. There is no user interface to view your trash, but it is still on disk if you are desperate to get it back.')
 
     #Send item on the Sent tab to trash
     def on_action_SentTrash(self):
         currentRow = self.ui.tableWidgetSent.currentRow()
-        ackdataToTrash = str(self.ui.tableWidgetSent.item(currentRow,3).data(Qt.UserRole).toPyObject())
-        t = (ackdataToTrash,)
-        sqlLock.acquire()
-        sqlSubmitQueue.put('''UPDATE sent SET folder='trash' WHERE ackdata=?''')
-        sqlSubmitQueue.put(t)
-        sqlReturnQueue.get()
-        sqlLock.release()
-        self.ui.textEditSentMessage.setText("")
-        self.ui.tableWidgetSent.removeRow(currentRow)
-        self.statusBar().showMessage('Moved item to trash. There is no user interface to view your trash, but it is still on disk if you are desperate to get it back.')
+        if currentRow >= 0:
+            ackdataToTrash = str(self.ui.tableWidgetSent.item(currentRow,3).data(Qt.UserRole).toPyObject())
+            t = (ackdataToTrash,)
+            sqlLock.acquire()
+            sqlSubmitQueue.put('''UPDATE sent SET folder='trash' WHERE ackdata=?''')
+            sqlSubmitQueue.put(t)
+            sqlReturnQueue.get()
+            sqlLock.release()
+            self.ui.textEditSentMessage.setText("")
+            self.ui.tableWidgetSent.removeRow(currentRow)
+            self.statusBar().showMessage('Moved item to trash. There is no user interface to view your trash, but it is still on disk if you are desperate to get it back.')
     def on_action_SentClipboard(self):
         currentRow = self.ui.tableWidgetSent.currentRow()
         addressAtCurrentRow = str(self.ui.tableWidgetSent.item(currentRow,0).data(Qt.UserRole).toPyObject())