gui: add BaseElectrumGui base class for guis

electrum/gui/__init__.py

@@ -9,3 +9,22 @@ from typing import TYPE_CHECKING
 if TYPE_CHECKING:
     from . import qt
     from . import kivy
+    from electrum.simple_config import SimpleConfig
+    from electrum.daemon import Daemon
+    from electrum.plugin import Plugins
+
+
+class BaseElectrumGui:
+    def __init__(self, *, config: 'SimpleConfig', daemon: 'Daemon', plugins: 'Plugins'):
+        self.config = config
+        self.daemon = daemon
+        self.plugins = plugins
+
+    def main(self) -> None:
+        raise NotImplementedError()
+
+    def stop(self) -> None:
+        """Stops the GUI.
+        This method must be thread-safe.
+        """
+        pass