Merge pull request #6062 from SomberNight/20200331_wizard_multisig_warning

wizard: add a warning to multisig wallet creation to backup xpubs

electrum/gui/kivy/uix/dialogs/installwizard.py

@@ -149,6 +149,18 @@ Builder.load_string('''
             range: 1, n.value
             step: 1
             value: 2
+    Widget
+        size_hint: 1, 1
+    Label:
+        id: backup_warning_label
+        color: root.text_color
+        size_hint: 1, None
+        text_size: self.width, None
+        height: self.texture_size[1]
+        opacity: int(m.value != n.value)
+        text: _("Warning: to be able to restore a multisig wallet, " \
+                "you should include the master public key for each cosigner " \
+                "in all of your backups.")
 
 
 <WizardChoiceDialog>

electrum/gui/qt/installwizard.py

@@ -664,18 +664,25 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
         def on_m(m):
             m_label.setText(_('Require {0} signatures').format(m))
             cw.set_m(m)
+            backup_warning_label.setVisible(cw.m != cw.n)
         def on_n(n):
             n_label.setText(_('From {0} cosigners').format(n))
             cw.set_n(n)
             m_edit.setMaximum(n)
+            backup_warning_label.setVisible(cw.m != cw.n)
         n_edit.valueChanged.connect(on_n)
         m_edit.valueChanged.connect(on_m)
-        on_n(2)
-        on_m(2)
         vbox = QVBoxLayout()
         vbox.addWidget(cw)
         vbox.addWidget(WWLabel(_("Choose the number of signatures needed to unlock funds in your wallet:")))
         vbox.addLayout(grid)
+        vbox.addSpacing(2 * char_width_in_lineedit())
+        backup_warning_label = WWLabel(_("Warning: to be able to restore a multisig wallet, "
+                                         "you should include the master public key for each cosigner "
+                                         "in all of your backups."))
+        vbox.addWidget(backup_warning_label)
+        on_n(2)
+        on_m(2)
         self.exec_layout(vbox, _("Multi-Signature Wallet"))
         m = int(m_edit.value())
         n = int(n_edit.value())