Fix top level window issue on Mac

Better, more generic fix superseding prior two patches.

gui/qt/__init__.py

@@ -64,7 +64,7 @@ class OpenFileEventFilter(QObject):
 
 
 
-class ElectrumGui(MessageBoxMixin):
+class ElectrumGui:
 
     def __init__(self, config, network, daemon, plugins):
         set_language(config.get('language'))

gui/qt/main_window.py

@@ -183,13 +183,6 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         return "%s/%s" % (PrintError.diagnostic_name(self),
                           self.wallet.basename() if self.wallet else "None")
 
-    def top_level_window(self, window=None):
-        window = window or self
-        for n, child in enumerate(window.children()):
-            if isinstance(child, WindowModalDialog):
-                return self.top_level_window(child)
-        return window
-
     def is_hidden(self):
         return self.isMinimized() or self.isHidden()
 
@@ -2085,11 +2078,10 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             verified = bitcoin.verify_message(address.text(), sig, message)
         except:
             verified = False
-        dialog = self.top_level_window()
         if verified:
-            dialog.show_message(_("Signature verified"))
+            self.show_message(_("Signature verified"))
         else:
-            dialog.show_error(_("Wrong signature"))
+            self.show_error(_("Wrong signature"))
 
 
     def sign_verify_message(self, address=''):
@@ -2137,7 +2129,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             message_e.setText(decrypted)
         except BaseException as e:
             traceback.print_exc(file=sys.stdout)
-            self.top_level_window().show_warning(str(e))
+            self.show_warning(str(e))
 
 
     def do_encrypt(self, message_e, pubkey_e, encrypted_e):
@@ -2148,7 +2140,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             encrypted_e.setText(encrypted)
         except BaseException as e:
             traceback.print_exc(file=sys.stdout)
-            self.top_level_window().show_warning(str(e))
+            self.show_warning(str(e))
 
 
     def encrypt_message(self, address = ''):

gui/qt/util.py

@@ -156,34 +156,38 @@ class CancelButton(QPushButton):
         self.clicked.connect(dialog.reject)
 
 class MessageBoxMixin(object):
+    def top_level_window(self, window=None):
+        window = window or self
+        for n, child in enumerate(window.children()):
+            if isinstance(child, WindowModalDialog):
+                return self.top_level_window(child)
+        return window
+
     def question(self, msg, parent=None, title=None, icon=None):
         Yes, No = QMessageBox.Yes, QMessageBox.No
         return self.msg_box(icon or QMessageBox.Question,
-                            parent or self, title or '',
+                            parent, title or '',
                             msg, buttons=Yes|No, defaultButton=No) == Yes
 
     def show_warning(self, msg, parent=None, title=None):
-        return self.msg_box(QMessageBox.Warning, parent or self,
+        return self.msg_box(QMessageBox.Warning, parent,
                             title or _('Warning'), msg)
 
     def show_error(self, msg, parent=None):
-        return self.msg_box(QMessageBox.Warning, parent or self,
+        return self.msg_box(QMessageBox.Warning, parent,
                             _('Error'), msg)
 
     def show_critical(self, msg, parent=None, title=None):
-        return self.msg_box(QMessageBox.Critical, parent or self,
+        return self.msg_box(QMessageBox.Critical, parent,
                             title or _('Critical Error'), msg)
 
     def show_message(self, msg, parent=None, title=None):
-        return self.msg_box(QMessageBox.Information, parent or self,
+        return self.msg_box(QMessageBox.Information, parent,
                             title or _('Information'), msg)
 
-    @staticmethod
-    def msg_box(icon, parent, title, text, buttons=QMessageBox.Ok,
+    def msg_box(self, icon, parent, title, text, buttons=QMessageBox.Ok,
                 defaultButton=QMessageBox.NoButton):
-        # handle e.g. ElectrumGui
-        if not isinstance(parent, QWidget):
-            parent = None
+        parent = parent or self.top_level_window()
         d = QMessageBox(icon, title, text, buttons, parent)
         d.setWindowModality(Qt.WindowModal)
         d.setDefaultButton(defaultButton)