Merge from google/flutter-desktop-embedding

.gitignore

@@ -1 +1,2 @@
+out/
 .DS_Store

.gn

@@ -0,0 +1 @@
+buildconfig = "//build/BUILDCONFIG.gn"

BUILD.gn

@@ -0,0 +1,22 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+group("gn_all") {
+  deps = [
+    "//library:flutter_embedder",
+    "//plugins/color_panel:color_panel",
+    "//plugins/file_chooser:file_chooser",
+    "//plugins/menubar:menubar",
+  ]
+}

Debugging.md

@@ -0,0 +1,80 @@
+# Debugging Desktop Flutter Applications
+
+While the current workflow for debugging on desktop is not ideal, it is
+possible to do most things, including source-level debugging and hot reload.
+
+Because this relies on workarounds for desktop not being a supported device,
+Flutter changes may break the workflows described below. We hope to extend
+the `flutter` tool to improve support, but in the meantime please file
+bugs in this project if you encounter issues with these instructions.
+
+## Getting the Observatory Port
+
+For all of these approaches, you will need the Observatory port of the
+desktop application. Usually, `flutter run` would handle this, but there's
+currently no way to `flutter run` a desktop application, so you will need to
+provide it manually.
+
+There are two options:
+
+1. **Find the port in the console.** After launching your application, check
+   the console output (your terminal in Linux,
+   [Console](https://developer.apple.com/library/archive/documentation/DeveloperTools/Conceptual/debugging_with_xcode/chapters/debugging_tools.html)
+   in Xcode, etc.) for a line like:
+   ```
+   Observatory listening on http://127.0.0.1:49494/
+   ```
+   The port in this case is `49494`. This will change on every run of the
+   application, so you'll need to repeat this every time you relaunch.
+
+1. **Hard-code the port**. In your embedder code, add `--observatory-port=49494`
+   (substituting a port of your choice) to the list of arguments passed to the
+   engine. If you are using `example/`, or code based on it, look for the
+   line that adds `--dart-non-checked-mode` for an example of adding arguments.
+   (Be sure not to add the `observatory-port` argument inside the `#if`,
+   however.)
+
+## Debugging
+
+### Command Line
+
+The `flutter attach` command can connect to a desktop Flutter application
+and provide the same interactive command line that `flutter run` would provide.
+In the directory of the Flutter portion of your application (e.g.,
+`/example/flutter_app`) run:
+
+```
+$ flutter attach --device-id=flutter-tester --debug-port=49494
+```
+
+Use the port you obtained above in place of `49494`. The `device-id` is
+necessary to bypass checks for an attached iOS or Android device.
+
+### VS Code
+
+Open the Flutter portion of your application (e.g., `/example/flutter_app`).
+Add a [launch
+configuration](https://code.visualstudio.com/docs/editor/debugging#_launch-configurations)
+like the following, substituting your Observatory port:
+
+```
+  {
+    "name": "Flutter Desktop Attach",
+    "request": "attach",
+    "deviceId": "flutter-tester",
+    "observatoryUri": "http://127.0.0.1:49494/",
+    "type": "dart"
+  }
+```
+
+You will likely want to hard-code your observatory port, otherwise you will
+need to change `launch.json` every time you relaunch the app.
+
+In addition to the Flutter debug commands, source-level debugging with pause,
+continue, variable inspection, etc. should all work.
+
+
+### IntelliJ
+
+**TBD**. If you test IntelliJ and are able to attach successfully, please
+contribute instructions!

README.md

@@ -46,13 +46,20 @@ In addition, there is:
   by the build systems, but in the future developer utilities providing
   some functionality similar to the `flutter` tool may be added.
 
-## Flutter Application Requirements
+## Flutter Application
+
+### Requirements
 
 Since desktop is not a supported platform for Flutter, be sure to read the
 [Flutter application requirements document](Flutter-Requirements.md) for
 important information about how to set up your Flutter application for use
 with this library.
 
+### Debugging
+
+Debugging of the Flutter side of a desktop application is possible, but requires
+[a modified workflow](Debugging.md).
+
 ## Feedback and Discussion
 
 For bug reports and specific feature requests, you can file GitHub issues. For

build/BUILD.gn

@@ -0,0 +1,32 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+config("defaults") {
+  cflags = [
+    "-std=c++14",
+    "-Wall",
+    "-Werror",
+    "-pthread",
+  ]
+  include_dirs = [
+    "//"
+  ]
+}
+
+config("shared_library_defaults") {
+  cflags = [
+    "-shared",
+    "-fPIC",
+  ]
+}

build/BUILDCONFIG.gn

@@ -0,0 +1,42 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set_default_toolchain("//third_party/chromium/build/toolchain:gcc")
+
+set_defaults("executable") {
+  configs = [ "//build:defaults" ]
+}
+set_defaults("static_library") {
+  configs = [ "//build:defaults" ]
+}
+set_defaults("shared_library") {
+  configs = [ "//build:defaults", "//build:shared_library_defaults" ]
+}
+set_defaults("published_shared_library") {
+  configs = [ "//build:defaults", "//build:shared_library_defaults" ]
+}
+
+if (host_os == "linux") {
+  is_linux = true
+  is_mac = false
+  is_win = false
+} else if (host_os == "mac") {
+  is_linux = false
+  is_mac = true
+  is_win = false
+} else if (host_os == "win") {
+  is_linux = false
+  is_mac = false
+  is_win = true
+}

build/flutter.gni

@@ -0,0 +1,21 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+declare_args() {
+  # The path to the Flutter tree to use for any Flutter operations or assets.
+  # If empty, assumes a directory called 'flutter' that is a sibling of this
+  # repository (like tools/flutter_location; this duplication avoids shelling
+  # out).
+  flutter_tree_path = rebase_path("../../flutter")
+}

build/linux/config/BUILD.gn

@@ -0,0 +1,31 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import("//third_party/chromium/build/config/linux/pkg_config.gni")
+
+pkg_config("gtk3") {
+  packages = [ "gtk+-3.0" ]
+}
+
+pkg_config("epoxy") {
+  packages = [ "epoxy" ]
+}
+
+pkg_config("x11") {
+  packages = [ "x11" ]
+}
+
+pkg_config("jsoncpp") {
+  packages = [ "jsoncpp" ]
+}

build/packaging.gni

@@ -0,0 +1,60 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Puts the public headers of the invoker in public_header_subdir
+# under the top-level include/ directory in the build output.
+#
+# This is intended to make consuming public headers of all the libraries built
+# by GN easy for outside build systems on Linux, by requiring only a single
+# include directory.
+if (is_linux) {
+  template("copy_includes") {
+    copy(target_name) {
+      assert(defined(invoker.sources),
+            "|sources| must be provided for copy_includes.")
+      forward_variables_from(invoker, [ "deps", "sources", "subdir" ])
+      output_dir = "$root_out_dir/include"
+      if (defined(subdir)) {
+        output_dir = "$output_dir/$subdir"
+      }
+      outputs = [ "$output_dir/{{source_file_part}}"]
+    }
+  }
+}
+
+# An abstraction for a shared library with associated headers that is intended
+# to be consumed from the build output.
+#
+# On Linux, this performs a copy_includes in addition to building the library.
+template("published_shared_library") {
+  template_target_name = target_name
+
+  if (is_linux) {
+    copy_includes("_publish_${template_target_name}_headers") {
+      sources = invoker.public
+      subdir = invoker.public_header_subdir
+    }
+
+    shared_library(template_target_name) {
+      forward_variables_from(invoker, "*")
+      assert(defined(public),
+            "|public| must be provided for published_shared_library.")
+
+      if (!defined(deps)) {
+        deps = []
+      }
+      deps += [ ":_publish_${template_target_name}_headers" ]
+    }
+  }
+}

example/README.md

@@ -13,7 +13,7 @@ functionality rather than a usable application.
 
 ## Building and Running the Example
 
-Since the exmaple is meant to show how the library would actually be used, it
+Since the example is meant to show how the library would actually be used, it
 deliberately uses platform-specific build systems that are separate from the
 rest of the project's build system.
 
@@ -54,7 +54,7 @@ Open the `Example Embedder` Visual Studio solution file under `windows\` and
 build the GLFW Example project.
 
 The resulting binary will be in `bin\x64\$(Configuration)\GLFW Example\`. It
-currently uses relative paths so much be run from the `windows\` directory:
+currently uses relative paths so must be run from the `windows\` directory:
 
 ```
 > ".\bin\x64\$(Configuration)\GLFW Example\GLFW Example.exe"

example/flutter_app/lib/main.dart

@@ -150,7 +150,8 @@ class _MyHomePage extends StatelessWidget {
     if (!colorPanel.showing) {
       colorPanel.show((color) {
         _AppState.of(context).setPrimaryColor(color);
-      });
+      // Setting the primary color to a non-opaque color raises an exception.
+      }, showAlpha: false); 
     }
   }
 
@@ -212,9 +213,9 @@ class FileChooserTestWidget extends StatelessWidget {
           onPressed: () {
             file_chooser.showSavePanel((result, paths) {
               Scaffold.of(context).showSnackBar(SnackBar(
-                    content: Text(_resultTextForFileChooserOperation(
-                        _FileChooserType.save, result, paths)),
-                  ));
+                content: Text(_resultTextForFileChooserOperation(
+                    _FileChooserType.save, result, paths)),
+              ));
             }, suggestedFileName: 'save_test.txt');
           },
         ),
@@ -223,9 +224,9 @@ class FileChooserTestWidget extends StatelessWidget {
           onPressed: () {
             file_chooser.showOpenPanel((result, paths) {
               Scaffold.of(context).showSnackBar(SnackBar(
-                    content: Text(_resultTextForFileChooserOperation(
-                        _FileChooserType.open, result, paths)),
-                  ));
+                content: Text(_resultTextForFileChooserOperation(
+                    _FileChooserType.open, result, paths)),
+              ));
             }, allowsMultipleSelection: true);
           },
         ),