Add iOS and macOS podspecs for cnativeapi plugin

Introduces cnativeapi.podspec files for iOS and macOS platforms to support Flutter plugin integration with native code. Also comments out multiple_window_example from the workspace in pubspec.yaml.

Author: lijy91

packages/cnativeapi/ios/cnativeapi.podspec

@@ -0,0 +1,43 @@
+#
+# To learn more about a Podspec see http://guides.cocoapods.org/syntax/podspec.html.
+# Run `pod lib lint cnativeapi.podspec` to validate before publishing.
+#
+Pod::Spec.new do |s|
+  s.name             = 'cnativeapi'
+  s.version          = '0.0.1'
+  s.summary          = 'A new Flutter plugin project.'
+  s.description      = <<-DESC
+A new Flutter plugin project.
+                       DESC
+  s.homepage         = 'http://example.com'
+  s.license          = { :file => '../LICENSE' }
+  s.author           = { 'Your Company' => 'email@example.com' }
+  s.source           = { :path => '.' }
+  s.source_files = 'cnativeapi/Sources/cnativeapi/**/*', '../cxx_impl/**/*.{cpp,h,mm}'
+  s.dependency 'Flutter'
+  s.platform = :ios, '13.0'
+
+  # Flutter.framework does not contain a i386 slice.
+   s.pod_target_xcconfig = {
+    'DEFINES_MODULE' => 'YES',
+    # Configure to compile .cpp files as Objective-C++
+    'CLANG_ENABLE_OBJC_ARC' => 'YES',
+    'CLANG_CXX_LANGUAGE_STANDARD' => 'c++17',
+    'CLANG_CXX_LIBRARY' => 'libc++',
+    'OTHER_CPLUSPLUSFLAGS' => '-std=c++17',
+    # Enable Objective-C++ compilation for .cpp files
+    'OTHER_CFLAGS' => '-DOBJC_OLD_DISPATCH_PROTOTYPES=0',
+    'GCC_PREPROCESSOR_DEFINITIONS' => '$(inherited)',
+    'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'i386',
+  }
+  s.swift_version = '5.0'
+
+  # Explicitly set file types to compile as Objective-C++
+  s.compiler_flags = '-x objective-c++'
+
+  # If your plugin requires a privacy manifest, for example if it uses any
+  # required reason APIs, update the PrivacyInfo.xcprivacy file to describe your
+  # plugin's privacy impact, and then uncomment this line. For more information,
+  # see https://developer.apple.com/documentation/bundleresources/privacy_manifest_files
+  # s.resource_bundles = {'cnativeapi_privacy' => ['cnativeapi/Sources/cnativeapi/PrivacyInfo.xcprivacy']}
+end

packages/cnativeapi/macos/cnativeapi.podspec

@@ -0,0 +1,44 @@
+#
+# To learn more about a Podspec see http://guides.cocoapods.org/syntax/podspec.html.
+# Run `pod lib lint cnativeapi.podspec` to validate before publishing.
+#
+Pod::Spec.new do |s|
+  s.name             = 'cnativeapi'
+  s.version          = '0.0.1'
+  s.summary          = 'A new Flutter plugin project.'
+  s.description      = <<-DESC
+A new Flutter plugin project.
+                       DESC
+  s.homepage         = 'http://example.com'
+  s.license          = { :file => '../LICENSE' }
+  s.author           = { 'Your Company' => 'email@example.com' }
+
+  s.source           = { :path => '.' }
+  s.source_files = 'cnativeapi/Sources/cnativeapi/**/*', '../cxx_impl/**/*.{cpp,h,mm}'
+
+  # If your plugin requires a privacy manifest, for example if it collects user
+  # data, update the PrivacyInfo.xcprivacy file to describe your plugin's
+  # privacy impact, and then uncomment this line. For more information,
+  # see https://developer.apple.com/documentation/bundleresources/privacy_manifest_files
+  # s.resource_bundles = {'cnativeapi_privacy' => ['cnativeapi/Sources/cnativeapi/PrivacyInfo.xcprivacy']}
+
+  s.dependency 'FlutterMacOS'
+
+  s.platform = :osx, '10.15'
+  s.pod_target_xcconfig = {
+    'DEFINES_MODULE' => 'YES',
+    # Configure to compile .cpp files as Objective-C++
+    'CLANG_ENABLE_OBJC_ARC' => 'YES',
+    'CLANG_CXX_LANGUAGE_STANDARD' => 'c++17',
+    'CLANG_CXX_LIBRARY' => 'libc++',
+    'OTHER_CPLUSPLUSFLAGS' => '-std=c++17',
+    # Enable Objective-C++ compilation for .cpp files
+    'OTHER_CFLAGS' => '-DOBJC_OLD_DISPATCH_PROTOTYPES=0',
+    'GCC_PREPROCESSOR_DEFINITIONS' => '$(inherited)',
+    'MACOSX_DEPLOYMENT_TARGET' => '10.15'
+  }
+  s.swift_version = '5.0'
+
+  # Explicitly set file types to compile as Objective-C++
+  s.compiler_flags = '-x objective-c++'
+end

pubspec.yaml

@@ -6,7 +6,7 @@ environment:
 workspace:
   - examples/display_example
   - examples/menu_example
-  - examples/multiple_window_example
+  # - examples/multiple_window_example
   - examples/storage_example
   - examples/tray_icon_example
   - examples/window_example