Fix kwin hanging when adding new notetype

https://forums.ankiweb.net/t/bug-anki-2-1-52-crashes-after-adding-new-note-type/20284

qt/aqt/models.py

@@ -144,22 +144,23 @@ class Models(QDialog):
         return self.mm.get(NotetypeId(self.models[row].id))
 
     def onAdd(self) -> None:
-        m = AddModel(self.mw, self).get()
-        if m:
+        def on_success(notetype: NotetypeDict) -> None:
             # if legacy add-ons already added the notetype, skip adding
-            if m["id"]:
+            if notetype["id"]:
                 return
 
             # prompt for name
-            text, ok = getText(tr.actions_name(), default=m["name"])
+            text, ok = getText(tr.actions_name(), default=notetype["name"], parent=self)
             if not ok or not text.strip():
                 return
-            m["name"] = text
+            notetype["name"] = text
 
-            add_notetype_legacy(parent=self, notetype=m).success(
+            add_notetype_legacy(parent=self, notetype=notetype).success(
                 self.refresh_list
             ).run_in_background()
 
+        AddModel(self.mw, on_success, self)
+
     def onDelete(self) -> None:
         if len(self.models) < 2:
             showInfo(tr.notetypes_please_add_another_note_type_first(), parent=self)
@@ -231,7 +232,12 @@ class Models(QDialog):
 class AddModel(QDialog):
     model: Optional[NotetypeDict]
 
-    def __init__(self, mw: AnkiQt, parent: Optional[QWidget] = None) -> None:
+    def __init__(
+        self,
+        mw: AnkiQt,
+        on_success: Callable[[NotetypeDict], None],
+        parent: Optional[QWidget] = None,
+    ) -> None:
         self.parent_ = parent or mw
         self.mw = mw
         self.col = mw.col
@@ -239,6 +245,7 @@ class AddModel(QDialog):
         self.model = None
         self.dialog = aqt.forms.addmodel.Ui_Dialog()
         self.dialog.setupUi(self)
+        self.setWindowModality(Qt.WindowModality.ApplicationModal)
         disable_help_button(self)
         # standard models
         self.notetypes: list[
@@ -259,10 +266,8 @@ class AddModel(QDialog):
         qconnect(s.activated, self.accept)
         # help
         qconnect(self.dialog.buttonBox.helpRequested, self.onHelp)
-
-    def get(self) -> Optional[NotetypeDict]:
-        self.exec()
-        return self.model
+        self.on_success = on_success
+        self.show()
 
     def reject(self) -> None:
         QDialog.reject(self)
@@ -275,6 +280,7 @@ class AddModel(QDialog):
         else:
             self.model = model(self.col)
         QDialog.accept(self)
+        self.on_success(self.model)
 
     def onHelp(self) -> None:
         openHelp(HelpPage.ADDING_A_NOTE_TYPE)