add checkpoint dialog to the kivy gui

gui/kivy/uix/dialogs/settings.py

@@ -113,6 +113,12 @@ Builder.load_string('''
                     title: _('Coin selection') + ': ' + self.status
                     description: "Coin selection method"
                     action: partial(root.coinselect_dialog, self)
+                CardSeparator
+                SettingsItem:
+                    status: root.checkpoint_status()
+                    title: _('Checkpoint') + ': ' + self.status
+                    description: _("Configure blockchain checkpoint")
+                    action: partial(root.checkpoint_dialog, self)
 ''')
 
 
@@ -134,6 +140,7 @@ class SettingsDialog(Factory.Popup):
         self._language_dialog = None
         self._unit_dialog = None
         self._coinselect_dialog = None
+        self._checkpoint_dialog = None
 
     def update(self):
         self.wallet = self.app.wallet
@@ -177,6 +184,21 @@ class SettingsDialog(Factory.Popup):
             self._coinselect_dialog = ChoiceDialog(_('Coin selection'), choosers, chooser_name, cb)
         self._coinselect_dialog.open()
 
+    def checkpoint_status(self):
+        height, value = self.app.network.blockchain.get_checkpoint()
+        return "Block %d"% height if height else _("Genesis block")
+
+    def checkpoint_dialog(self, item, dt):
+        from checkpoint_dialog import CheckpointDialog
+        if self._checkpoint_dialog is None:
+            def callback(height, value):
+                if value:
+                    self.app.network.blockchain.set_checkpoint(height, value)
+                    item.status = self.checkpoint_status()
+
+            self._checkpoint_dialog = CheckpointDialog(self.app.network, callback)
+        self._checkpoint_dialog.open()
+
     def network_dialog(self, item, dt):
         if self._network_dialog is None:
             server, port, protocol, proxy, auto_connect = self.app.network.get_parameters()