Add create command for plugin support

templates/plugin/.gitignore

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+flutter/

templates/plugin/CMakeLists.txt.tmpl

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+cmake_minimum_required(VERSION 3.15)
+set(PROJECT_NAME "{{projectName}}")
+project(${PROJECT_NAME} LANGUAGES CXX)
+
+# This value is used when generating builds using this plugin, so it must
+# not be changed
+set(PLUGIN_NAME "{{projectName}}_plugin")
+
+add_library(${PLUGIN_NAME} SHARED
+  "{{pluginClassSnakeCase}}.cc"
+)
+apply_standard_settings(${PLUGIN_NAME})
+set_target_properties(${PLUGIN_NAME} PROPERTIES
+  CXX_VISIBILITY_PRESET hidden)
+target_compile_definitions(${PLUGIN_NAME} PRIVATE FLUTTER_PLUGIN_IMPL)
+target_include_directories(${PLUGIN_NAME} INTERFACE
+  "${CMAKE_CURRENT_SOURCE_DIR}/include")
+target_link_libraries(${PLUGIN_NAME} PRIVATE flutter flutter_wrapper_plugin)
+
+# List of absolute paths to libraries that should be bundled with the plugin
+set({{projectName}}_bundled_libraries
+  ""
+  PARENT_SCOPE
+)

templates/plugin/include/projectName.tmpl/pluginClassSnakeCase.h.tmpl

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+#ifndef FLUTTER_PLUGIN_{{pluginClassCapitalSnakeCase}}_H_
+#define FLUTTER_PLUGIN_{{pluginClassCapitalSnakeCase}}_H_
+
+#include <flutter_plugin_registrar.h>
+
+#ifdef FLUTTER_PLUGIN_IMPL
+#define FLUTTER_PLUGIN_EXPORT __declspec(dllexport)
+#else
+#define FLUTTER_PLUGIN_EXPORT __declspec(dllimport)
+#endif
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+FLUTTER_PLUGIN_EXPORT void {{pluginClass}}RegisterWithRegistrar(
+    FlutterDesktopPluginRegistrarRef registrar);
+
+#if defined(__cplusplus)
+}  // extern "C"
+#endif
+
+#endif  // FLUTTER_PLUGIN_{{pluginClassCapitalSnakeCase}}_H_

templates/plugin/pluginClassSnakeCase.cc.tmpl

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+#include "include/{{projectName}}/{{pluginClassSnakeCase}}.h"
+
+#include <flutter/method_channel.h>
+#include <flutter/plugin_registrar.h>
+#include <flutter/standard_method_codec.h>
+
+#include <map>
+#include <memory>
+#include <sstream>
+
+namespace {
+
+class {{pluginClass}} : public flutter::Plugin {
+ public:
+  static void RegisterWithRegistrar(flutter::PluginRegistrar *registrar);
+
+  {{pluginClass}}();
+
+  virtual ~{{pluginClass}}();
+
+ private:
+  // Called when a method is called on this plugin's channel from Dart.
+  void HandleMethodCall(
+      const flutter::MethodCall<flutter::EncodableValue> &method_call,
+      std::unique_ptr<flutter::MethodResult<flutter::EncodableValue>> result);
+};
+
+// static
+void {{pluginClass}}::RegisterWithRegistrar(
+    flutter::PluginRegistrar *registrar) {
+  auto channel =
+      std::make_unique<flutter::MethodChannel<flutter::EncodableValue>>(
+          registrar->messenger(), "{{projectName}}",
+          &flutter::StandardMethodCodec::GetInstance());
+
+  auto plugin = std::make_unique<{{pluginClass}}>();
+
+  channel->SetMethodCallHandler(
+      [plugin_pointer = plugin.get()](const auto &call, auto result) {
+        plugin_pointer->HandleMethodCall(call, std::move(result));
+      });
+
+  registrar->AddPlugin(std::move(plugin));
+}
+
+{{pluginClass}}::{{pluginClass}}() {}
+
+{{pluginClass}}::~{{pluginClass}}() {}
+
+void {{pluginClass}}::HandleMethodCall(
+    const flutter::MethodCall<flutter::EncodableValue> &method_call,
+    std::unique_ptr<flutter::MethodResult<flutter::EncodableValue>> result) {
+  if (method_call.method_name().compare("getPlatformVersion") == 0) {
+    std::ostringstream version_stream;
+    version_stream << "eLinux";
+    result->Success(flutter::EncodableValue(version_stream.str()));
+  } else {
+    result->NotImplemented();
+  }
+}
+
+}  // namespace
+
+void {{pluginClass}}RegisterWithRegistrar(
+    FlutterDesktopPluginRegistrarRef registrar) {
+  {{pluginClass}}::RegisterWithRegistrar(
+      flutter::PluginRegistrarManager::GetInstance()
+          ->GetRegistrar<flutter::PluginRegistrar>(registrar));
+}