qt addresses list: use IntEnum for dropdown filters

electrum/gui/qt/address_list.py

@@ -38,6 +38,34 @@ from electrum.wallet import InternalAddressCorruption
 from .util import MyTreeView, MONOSPACE_FONT, ColorScheme, webopen
 
 
+class AddressUsageStateFilter(IntEnum):
+    ALL = 0
+    UNUSED = 1
+    FUNDED = 2
+    USED_AND_EMPTY = 3
+
+    def ui_text(self) -> str:
+        return {
+            self.ALL: _('All'),
+            self.UNUSED: _('Unused'),
+            self.FUNDED: _('Funded'),
+            self.USED_AND_EMPTY: _('Used'),
+        }[self]
+
+
+class AddressTypeFilter(IntEnum):
+    ALL = 0
+    RECEIVING = 1
+    CHANGE = 2
+
+    def ui_text(self) -> str:
+        return {
+            self.ALL: _('All'),
+            self.RECEIVING: _('Receiving'),
+            self.CHANGE: _('Change'),
+        }[self]
+
+
 class AddressList(MyTreeView):
 
     class Columns(IntEnum):
@@ -54,16 +82,16 @@ class AddressList(MyTreeView):
         super().__init__(parent, self.create_menu, stretch_column=self.Columns.LABEL)
         self.setSelectionMode(QAbstractItemView.ExtendedSelection)
         self.setSortingEnabled(True)
-        self.show_change = 0
+        self.show_change = AddressTypeFilter.ALL  # type: AddressTypeFilter
-        self.show_used = 0
+        self.show_used = AddressUsageStateFilter.ALL  # type: AddressUsageStateFilter
         self.change_button = QComboBox(self)
         self.change_button.currentIndexChanged.connect(self.toggle_change)
-        for t in [_('All'), _('Receiving'), _('Change')]:
+        for addr_type in AddressTypeFilter.__members__.values():  # type: AddressTypeFilter
-            self.change_button.addItem(t)
+            self.change_button.addItem(addr_type.ui_text())
         self.used_button = QComboBox(self)
         self.used_button.currentIndexChanged.connect(self.toggle_used)
-        for t in [_('All'), _('Unused'), _('Funded'), _('Used')]:
+        for addr_usage_state in AddressUsageStateFilter.__members__.values():  # type: AddressUsageStateFilter
-            self.used_button.addItem(t)
+            self.used_button.addItem(addr_usage_state.ui_text())
         self.setModel(QStandardItemModel(self))
         self.update()
 
@@ -71,8 +99,8 @@ class AddressList(MyTreeView):
         return QLabel(_("Filter:")), self.change_button, self.used_button
 
     def on_hide_toolbar(self):
-        self.show_change = 0
+        self.show_change = AddressTypeFilter.ALL  # type: AddressTypeFilter
-        self.show_used = 0
+        self.show_used = AddressUsageStateFilter.ALL  # type: AddressUsageStateFilter
         self.update()
 
     def save_toolbar_state(self, state, config):
@@ -94,25 +122,25 @@ class AddressList(MyTreeView):
         }
         self.update_headers(headers)
 
-    def toggle_change(self, state):
+    def toggle_change(self, state: int):
         if state == self.show_change:
             return
-        self.show_change = state
+        self.show_change = AddressTypeFilter(state)
         self.update()
 
-    def toggle_used(self, state):
+    def toggle_used(self, state: int):
         if state == self.show_used:
             return
-        self.show_used = state
+        self.show_used = AddressUsageStateFilter(state)
         self.update()
 
     @profiler
     def update(self):
         self.wallet = self.parent.wallet
         current_address = self.current_item_user_role(col=self.Columns.LABEL)
-        if self.show_change == 1:
+        if self.show_change == AddressTypeFilter.RECEIVING:
             addr_list = self.wallet.get_receiving_addresses()
-        elif self.show_change == 2:
+        elif self.show_change == AddressTypeFilter.CHANGE:
             addr_list = self.wallet.get_change_addresses()
         else:
             addr_list = self.wallet.get_addresses()
@@ -126,11 +154,11 @@ class AddressList(MyTreeView):
             c, u, x = self.wallet.get_addr_balance(address)
             balance = c + u + x
             is_used_and_empty = self.wallet.is_used(address) and balance == 0
-            if self.show_used == 1 and (balance or is_used_and_empty):
+            if self.show_used == AddressUsageStateFilter.UNUSED and (balance or is_used_and_empty):
                 continue
-            if self.show_used == 2 and balance == 0:
+            if self.show_used == AddressUsageStateFilter.FUNDED and balance == 0:
                 continue
-            if self.show_used == 3 and not is_used_and_empty:
+            if self.show_used == AddressUsageStateFilter.USED_AND_EMPTY and not is_used_and_empty:
                 continue
             balance_text = self.parent.format_amount(balance, whitespaces=True)
             # create item