Merge pull request #1131 from quxiaozha/master

Use display_id = 0 as default when no display id provided

Author: codeskyblue

uiautomator2/__init__.py

@@ -80,7 +80,7 @@ def screenshot(self, filename: Optional[str] = None, format="pillow", display_id
                 jpg_raw = base64.b64decode(base64_data)
                 pil_img = Image.open(io.BytesIO(jpg_raw))
             else:
-                pil_img = self._dev.screenshot(display_id=display_id)
+                pil_img = self._dev.screenshot(display_id=0)
         else:
             pil_img = self._dev.screenshot(display_id=display_id)
 
@@ -960,4 +960,4 @@ def connect_usb(serial: Optional[str] = None) -> Device:
     """
     if not serial:
         serial = adbutils.adb.device()
-    return Device(serial)
+    return Device(serial)