From 878f3e3490e1d008cbe8ad4ebf5083dd03e537c3 Mon Sep 17 00:00:00 2001
From: Feodor Fitsner <feodor@appveyor.com>
Date: Sun, 12 Jun 2022 20:37:32 -0700
Subject: [PATCH 1/6] UserControl draft

---
 sdk/python/flet/__init__.py     |  1 +
 sdk/python/flet/control.py      | 12 ++++++++---
 sdk/python/flet/page.py         |  6 ++++++
 sdk/python/flet/user_control.py | 37 +++++++++++++++++++++++++++++++++
 4 files changed, 53 insertions(+), 3 deletions(-)
 create mode 100644 sdk/python/flet/user_control.py

diff --git a/sdk/python/flet/__init__.py b/sdk/python/flet/__init__.py
index 2b6f43ac0..6a121099e 100644
--- a/sdk/python/flet/__init__.py
+++ b/sdk/python/flet/__init__.py
@@ -40,4 +40,5 @@
 from flet.text_button import TextButton
 from flet.textfield import TextField
 from flet.theme import Theme
+from flet.user_control import UserControl
 from flet.vertical_divider import VerticalDivider
diff --git a/sdk/python/flet/control.py b/sdk/python/flet/control.py
index 151c0db6b..253b08d4e 100644
--- a/sdk/python/flet/control.py
+++ b/sdk/python/flet/control.py
@@ -11,8 +11,10 @@
 from flet.embed_json_encoder import EmbedJsonEncoder
 from flet.margin import Margin
 from flet.padding import Padding
+from flet.page import Page
 from flet.protocol import Command
 from flet.ref import Ref
+from flet.user_control import UserControl
 
 try:
     from typing import Literal
@@ -179,11 +181,11 @@ def _id(self, value):
 
     # page
     @property
-    def page(self):
+    def page(self) -> Page:
         return self.__page
 
     @page.setter
-    def page(self, page):
+    def page(self, page: Page):
         self.__page = page
 
     # uid
@@ -306,7 +308,8 @@ def build_update_commands(self, index, added_controls, commands):
                 # unchanged control
                 for h in previous_ints[a1:a2]:
                     ctrl = hashes[h]
-                    ctrl.build_update_commands(index, added_controls, commands)
+                    if not isinstance(ctrl, UserControl):
+                        ctrl.build_update_commands(index, added_controls, commands)
                     n += 1
             elif tag == "replace":
                 ids = []
@@ -358,6 +361,9 @@ def _remove_control_recursively(self, index, control):
             self._remove_control_recursively(index, child)
 
         if control.__uid in index:
+            if isinstance(control, UserControl):
+                control.will_unmount()
+
             del index[control.__uid]
 
     # private methods
diff --git a/sdk/python/flet/page.py b/sdk/python/flet/page.py
index 14bb90f78..b8a15abec 100644
--- a/sdk/python/flet/page.py
+++ b/sdk/python/flet/page.py
@@ -24,6 +24,7 @@
 from flet.pubsub import PubSub
 from flet.snack_bar import SnackBar
 from flet.theme import Theme
+from flet.user_control import UserControl
 
 try:
     from typing import Literal
@@ -117,6 +118,11 @@ def __update(self, *controls):
 
                     # add to index
                     self._index[id] = added_controls[n]
+
+                    # call UserControl.did_mount
+                    if isinstance(added_controls[n], UserControl):
+                        added_controls[n].did_mount()
+
                     n += 1
 
     def add(self, *controls):
diff --git a/sdk/python/flet/user_control.py b/sdk/python/flet/user_control.py
new file mode 100644
index 000000000..9056185ae
--- /dev/null
+++ b/sdk/python/flet/user_control.py
@@ -0,0 +1,37 @@
+import logging
+from typing import Union
+
+from flet.control import OptionalNumber
+from flet.ref import Ref
+from flet.stack import Stack
+
+
+class UserControl(Stack):
+    # def __init__(
+    #     self,
+    #     ref: Ref = None,
+    #     width: OptionalNumber = None,
+    #     height: OptionalNumber = None,
+    #     expand: Union[bool, int] = None,
+    #     opacity: OptionalNumber = None,
+    #     visible: bool = None,
+    #     disabled: bool = None,
+    #     data: any = None,
+    # ):
+    #     Stack.__init__(
+    #         self,
+    #         ref=ref,
+    #         width=width,
+    #         height=height,
+    #         expand=expand,
+    #         opacity=opacity,
+    #         visible=visible,
+    #         disabled=disabled,
+    #         data=data,
+    #     )
+
+    def did_mount(self):
+        logging.debug(f"UserControl.did_mount(): {self.uid}")
+
+    def will_unmount(self):
+        logging.debug(f"UserControl.will_unmount(): {self.uid}")

From ce7704108f45ad7e92950eb8b149a6aeb057b421 Mon Sep 17 00:00:00 2001
From: Feodor Fitsner <feodor@appveyor.com>
Date: Mon, 13 Jun 2022 17:07:45 -0700
Subject: [PATCH 2/6] Do not reference UserControl

---
 sdk/python/flet/control.py      | 14 ++++++--------
 sdk/python/flet/page.py         |  3 +--
 sdk/python/flet/user_control.py |  3 +++
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/sdk/python/flet/control.py b/sdk/python/flet/control.py
index 253b08d4e..07ef0f5c6 100644
--- a/sdk/python/flet/control.py
+++ b/sdk/python/flet/control.py
@@ -11,10 +11,8 @@
 from flet.embed_json_encoder import EmbedJsonEncoder
 from flet.margin import Margin
 from flet.padding import Padding
-from flet.page import Page
 from flet.protocol import Command
 from flet.ref import Ref
-from flet.user_control import UserControl
 
 try:
     from typing import Literal
@@ -88,8 +86,8 @@ def __init__(
         if ref:
             ref.current = self
 
-    def _assign(self, variable):
-        variable = self
+    def _is_user_control(self):
+        return False
 
     def _get_children(self):
         return []
@@ -181,11 +179,11 @@ def _id(self, value):
 
     # page
     @property
-    def page(self) -> Page:
+    def page(self):
         return self.__page
 
     @page.setter
-    def page(self, page: Page):
+    def page(self, page):
         self.__page = page
 
     # uid
@@ -308,7 +306,7 @@ def build_update_commands(self, index, added_controls, commands):
                 # unchanged control
                 for h in previous_ints[a1:a2]:
                     ctrl = hashes[h]
-                    if not isinstance(ctrl, UserControl):
+                    if not ctrl._is_user_control():
                         ctrl.build_update_commands(index, added_controls, commands)
                     n += 1
             elif tag == "replace":
@@ -361,7 +359,7 @@ def _remove_control_recursively(self, index, control):
             self._remove_control_recursively(index, child)
 
         if control.__uid in index:
-            if isinstance(control, UserControl):
+            if control._is_user_control():
                 control.will_unmount()
 
             del index[control.__uid]
diff --git a/sdk/python/flet/page.py b/sdk/python/flet/page.py
index b8a15abec..5e0d4bde9 100644
--- a/sdk/python/flet/page.py
+++ b/sdk/python/flet/page.py
@@ -24,7 +24,6 @@
 from flet.pubsub import PubSub
 from flet.snack_bar import SnackBar
 from flet.theme import Theme
-from flet.user_control import UserControl
 
 try:
     from typing import Literal
@@ -120,7 +119,7 @@ def __update(self, *controls):
                     self._index[id] = added_controls[n]
 
                     # call UserControl.did_mount
-                    if isinstance(added_controls[n], UserControl):
+                    if added_controls[n]._is_user_control():
                         added_controls[n].did_mount()
 
                     n += 1
diff --git a/sdk/python/flet/user_control.py b/sdk/python/flet/user_control.py
index 9056185ae..b7da42a0d 100644
--- a/sdk/python/flet/user_control.py
+++ b/sdk/python/flet/user_control.py
@@ -30,6 +30,9 @@ class UserControl(Stack):
     #         data=data,
     #     )
 
+    def _is_user_control(self):
+        return True
+
     def did_mount(self):
         logging.debug(f"UserControl.did_mount(): {self.uid}")
 

From 312e44ef94813bc4d0580feb2e5e9dc9d05b1d6d Mon Sep 17 00:00:00 2001
From: Feodor Fitsner <feodor@appveyor.com>
Date: Wed, 15 Jun 2022 08:05:50 -0700
Subject: [PATCH 3/6] UserControl complete

---
 sdk/python/flet/control.py      | 14 +++++----
 sdk/python/flet/page.py         |  5 ++--
 sdk/python/flet/user_control.py | 52 ++++++++++++---------------------
 3 files changed, 30 insertions(+), 41 deletions(-)

diff --git a/sdk/python/flet/control.py b/sdk/python/flet/control.py
index 07ef0f5c6..fc5a88464 100644
--- a/sdk/python/flet/control.py
+++ b/sdk/python/flet/control.py
@@ -86,9 +86,15 @@ def __init__(
         if ref:
             ref.current = self
 
-    def _is_user_control(self):
+    def _is_isolated(self):
         return False
 
+    def did_mount(self):
+        pass
+
+    def will_unmount(self):
+        pass
+
     def _get_children(self):
         return []
 
@@ -306,7 +312,7 @@ def build_update_commands(self, index, added_controls, commands):
                 # unchanged control
                 for h in previous_ints[a1:a2]:
                     ctrl = hashes[h]
-                    if not ctrl._is_user_control():
+                    if not ctrl._is_isolated():
                         ctrl.build_update_commands(index, added_controls, commands)
                     n += 1
             elif tag == "replace":
@@ -359,9 +365,7 @@ def _remove_control_recursively(self, index, control):
             self._remove_control_recursively(index, child)
 
         if control.__uid in index:
-            if control._is_user_control():
-                control.will_unmount()
-
+            control.will_unmount()
             del index[control.__uid]
 
     # private methods
diff --git a/sdk/python/flet/page.py b/sdk/python/flet/page.py
index 5e0d4bde9..cf40db31e 100644
--- a/sdk/python/flet/page.py
+++ b/sdk/python/flet/page.py
@@ -118,9 +118,8 @@ def __update(self, *controls):
                     # add to index
                     self._index[id] = added_controls[n]
 
-                    # call UserControl.did_mount
-                    if added_controls[n]._is_user_control():
-                        added_controls[n].did_mount()
+                    # call Control.did_mount
+                    added_controls[n].did_mount()
 
                     n += 1
 
diff --git a/sdk/python/flet/user_control.py b/sdk/python/flet/user_control.py
index b7da42a0d..44180fed6 100644
--- a/sdk/python/flet/user_control.py
+++ b/sdk/python/flet/user_control.py
@@ -1,40 +1,26 @@
-import logging
-from typing import Union
+from typing import List
 
-from flet.control import OptionalNumber
-from flet.ref import Ref
+from flet.control import Control
 from flet.stack import Stack
 
 
 class UserControl(Stack):
-    # def __init__(
-    #     self,
-    #     ref: Ref = None,
-    #     width: OptionalNumber = None,
-    #     height: OptionalNumber = None,
-    #     expand: Union[bool, int] = None,
-    #     opacity: OptionalNumber = None,
-    #     visible: bool = None,
-    #     disabled: bool = None,
-    #     data: any = None,
-    # ):
-    #     Stack.__init__(
-    #         self,
-    #         ref=ref,
-    #         width=width,
-    #         height=height,
-    #         expand=expand,
-    #         opacity=opacity,
-    #         visible=visible,
-    #         disabled=disabled,
-    #         data=data,
-    #     )
+    def __init__(self):
+        super().__init__()
+        content = self.build()
+        if isinstance(content, Control):
+            self.controls = [content]
+        elif isinstance(content, List) and all(
+            isinstance(control, Control) for control in content
+        ):
+            self.controls = content
+        else:
+            raise Exception(
+                f"{self.__class__.__name__}.build() method must be implemented and returning either Control or List[Control]."
+            )
 
-    def _is_user_control(self):
-        return True
-
-    def did_mount(self):
-        logging.debug(f"UserControl.did_mount(): {self.uid}")
+    def build(self):
+        pass
 
-    def will_unmount(self):
-        logging.debug(f"UserControl.will_unmount(): {self.uid}")
+    def _is_isolated(self):
+        return True

From 707950c305f1791850dd59f8b936ef6bd774a9a3 Mon Sep 17 00:00:00 2001
From: Feodor Fitsner <feodor@appveyor.com>
Date: Wed, 15 Jun 2022 08:05:58 -0700
Subject: [PATCH 4/6] Go 1.18.3

---
 .appveyor.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.appveyor.yml b/.appveyor.yml
index 851ad3318..7afd46d1b 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -9,7 +9,7 @@ skip_commits:
     - "*.md"
 
 environment:
-  GO_VERSION: 1.18.1
+  GO_VERSION: 1.18.3
   GO_TAGS: --tags release
   python_version: 3.10
   GITHUB_TOKEN:

From c5bf1b58e40f77f74eeb4a0055c4cc93fcb56280 Mon Sep 17 00:00:00 2001
From: Feodor Fitsner <feodor@appveyor.com>
Date: Wed, 15 Jun 2022 08:41:36 -0700
Subject: [PATCH 5/6] An ability to choose Flutter web renderer

---
 client/web/index.html   |  2 ++
 sdk/python/flet/flet.py | 21 ++++++++++++++++++---
 server/config/config.go |  5 +++++
 server/server/server.go | 17 +++++++++++++----
 4 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/client/web/index.html b/client/web/index.html
index 629f9d5a2..372794bae 100644
--- a/client/web/index.html
+++ b/client/web/index.html
@@ -19,6 +19,8 @@
   <title>Flet</title>
   <link rel="manifest" href="manifest.json">
 
+  <!-- flutterWebRenderer -->
+
   <script>
     // The value below is injected by flutter build, do not touch.
     var serviceWorkerVersion = null;
diff --git a/sdk/python/flet/flet.py b/sdk/python/flet/flet.py
index 8605e8846..5a159d7c3 100644
--- a/sdk/python/flet/flet.py
+++ b/sdk/python/flet/flet.py
@@ -35,9 +35,16 @@
     FLET_APP,
 ]
 
+WebRenderer = Literal[None, "auto", "html", "canvaskit"]
+
 
 def page(
-    name="", port=0, permissions=None, view: AppViewer = WEB_BROWSER, assets_dir=None
+    name="",
+    port=0,
+    permissions=None,
+    view: AppViewer = WEB_BROWSER,
+    assets_dir=None,
+    web_renderer=None,
 ):
     conn = _connect_internal(
         page_name=name,
@@ -45,6 +52,7 @@ def page(
         is_app=False,
         permissions=permissions,
         assets_dir=assets_dir,
+        web_renderer=web_renderer,
     )
     print("Page URL:", conn.page_url)
     page = Page(conn, constants.ZERO_SESSION)
@@ -63,6 +71,7 @@ def app(
     permissions=None,
     view: AppViewer = FLET_APP,
     assets_dir=None,
+    web_renderer=None,
 ):
 
     if target == None:
@@ -75,6 +84,7 @@ def app(
         permissions=permissions,
         session_handler=target,
         assets_dir=assets_dir,
+        web_renderer=web_renderer,
     )
     print("App URL:", conn.page_url)
 
@@ -129,6 +139,7 @@ def _connect_internal(
     permissions=None,
     session_handler=None,
     assets_dir=None,
+    web_renderer=None,
 ):
     if share and server == None:
         server = constants.HOSTED_SERVICE_URL
@@ -141,7 +152,7 @@ def _connect_internal(
         # page with a custom port starts detached process
         attached = False if not is_app and port != 0 else True
 
-        port = _start_flet_server(port, attached, assets_dir)
+        port = _start_flet_server(port, attached, assets_dir, web_renderer)
         server = f"http://localhost:{port}"
 
     connected = threading.Event()
@@ -209,7 +220,7 @@ def _on_ws_failed_connect():
     return conn
 
 
-def _start_flet_server(port, attached, assets_dir):
+def _start_flet_server(port, attached, assets_dir, web_renderer):
 
     if port == 0:
         port = _get_free_tcp_port()
@@ -243,6 +254,10 @@ def _start_flet_server(port, attached, assets_dir):
         logging.info(f"Assets path configured: {assets_dir}")
         fletd_env["FLET_STATIC_ROOT_DIR"] = assets_dir
 
+    if web_renderer not in [None, "", "auto"]:
+        logging.info(f"Web renderer configured: {web_renderer}")
+        fletd_env["FLET_WEB_RENDERER"] = web_renderer
+
     args = [fletd_path, "--port", str(port)]
 
     creationflags = 0
diff --git a/server/config/config.go b/server/config/config.go
index bfcfb30ef..b2098a409 100644
--- a/server/config/config.go
+++ b/server/config/config.go
@@ -71,6 +71,7 @@ const (
 
 	// development
 	staticRootDir = "STATIC_ROOT_DIR"
+	webRenderer   = "WEB_RENDERER"
 )
 
 func init() {
@@ -278,3 +279,7 @@ func MasterSecretKey() string {
 func StaticRootDir() string {
 	return viper.GetString(staticRootDir)
 }
+
+func WebRenderer() string {
+	return viper.GetString(webRenderer)
+}
diff --git a/server/server/server.go b/server/server/server.go
index 4db6809b4..4d7f01baa 100644
--- a/server/server/server.go
+++ b/server/server/server.go
@@ -105,10 +105,19 @@ func Start(ctx context.Context, wg *sync.WaitGroup, serverPort int) {
 			index, _ := assetsFS.Open(siteDefaultDocument)
 			indexData, _ := ioutil.ReadAll(index)
 
-			c.Data(http.StatusOK, "text/html",
-				bytes.Replace(indexData,
-					[]byte("<base href=\"/\">"),
-					[]byte("<base href=\""+urlPath+"\">"), 1))
+			// base path
+			indexData = bytes.Replace(indexData,
+				[]byte("<base href=\"/\">"),
+				[]byte("<base href=\""+urlPath+"\">"), 1)
+
+			// web renderer
+			if config.WebRenderer() != "" {
+				indexData = bytes.Replace(indexData,
+					[]byte("<!-- flutterWebRenderer -->"),
+					[]byte("<script>window.flutterWebRenderer=\""+config.WebRenderer()+"\";</script>"), 1)
+			}
+
+			c.Data(http.StatusOK, "text/html", indexData)
 		} else {
 			// API not found
 			c.JSON(http.StatusNotFound, gin.H{

From 0436f8b49c969245f1e129ecf29d5d654913f711 Mon Sep 17 00:00:00 2001
From: Feodor Fitsner <feodor@appveyor.com>
Date: Wed, 15 Jun 2022 09:32:41 -0700
Subject: [PATCH 6/6] page.set_clipboard(), page.show_snack_bar()

---
 sdk/python/flet/clipboard.py |  3 +++
 sdk/python/flet/page.py      | 20 ++++++++++----------
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/sdk/python/flet/clipboard.py b/sdk/python/flet/clipboard.py
index a19021763..cdd63e755 100644
--- a/sdk/python/flet/clipboard.py
+++ b/sdk/python/flet/clipboard.py
@@ -36,6 +36,9 @@ def __init__(
     def _get_control_name(self):
         return "clipboard"
 
+    def _is_isolated(self):
+        return True
+
     # value
     @property
     def value(self):
diff --git a/sdk/python/flet/page.py b/sdk/python/flet/page.py
index cf40db31e..771c044a6 100644
--- a/sdk/python/flet/page.py
+++ b/sdk/python/flet/page.py
@@ -223,6 +223,16 @@ def _send_command(self, name: str, values: List[str]):
             Command(0, name, values, None, None),
         )
 
+    @beartype
+    def set_clipboard(self, value: str):
+        self.__offstage.clipboard.value = value
+        self.__offstage.clipboard.update()
+
+    @beartype
+    def show_snack_bar(self, snack_bar: SnackBar):
+        self.__offstage.snack_bar = snack_bar
+        self.__offstage.update()
+
     # url
     @property
     def url(self):
@@ -345,16 +355,6 @@ def fonts(self, value: Optional[Dict[str, str]]):
         self.__fonts = value
         self._set_attr_json("fonts", value)
 
-    # clipboard
-    @property
-    def clipboard(self):
-        return self.__offstage.clipboard.value
-
-    @clipboard.setter
-    @beartype
-    def clipboard(self, value: Optional[str]):
-        self.__offstage.clipboard.value = value
-
     # splash
     @property
     def splash(self):