Flutter中获取监听屏幕方向、锁定屏幕方向

print("当前屏幕方向：${MediaQuery.of(context).orientation}");

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return OrientationBuilder(
      builder: (BuildContext context, Orientation orientation) {
        print("当前屏幕的方向是：$orientation");
        return MaterialApp(
          title: 'Flutter Demo',
          home: MyHomePage(title: 'Flutter Demo Home Page'),
        );
      },
    );
  }
}

E/flutter (12370): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: ServicesBinding.defaultBinaryMessenger was accessed before the binding was initialized.
E/flutter (12370): If you're running an application and need to access the binary messenger before `runApp()` has been called (for example, during plugin initialization), then you need to explicitly call the `WidgetsFlutterBinding.ensureInitialized()` first.
E/flutter (12370): If you're running a test, you can call the `TestWidgetsFlutterBinding.ensureInitialized()` as the first line in your test's `main()` method to initialize the binding.

void main() {
  WidgetsFlutterBinding.ensureInitialized();
  SystemChrome.setPreferredOrientations(
          [DeviceOrientation.portraitDown, DeviceOrientation.portraitUp])
      .then((value) => runApp(MyApp()));
}

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.surecall.fusion_pro"
    xmlns:tools="http://schemas.android.com/tools">
  
   <application
        android:label="Flutter App"
        android:icon="@mipmap/ic_launcher">
        <activity
            android:name=".MainActivity"
            android:launchMode="singleTop"
            android:theme="@style/LaunchTheme"
            android:screenOrientation="portrait"
            ...>
        </activity>
        ...
    </application>
</manifest>

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  ....
  <!--iphone的屏幕方向设置-->
  <key>UISupportedInterfaceOrientations</key>
  <array>
    <string>UIInterfaceOrientationPortrait</string>
    <!--
    <string>UIInterfaceOrientationPortraitUpsideDown</string>
    <string>UIInterfaceOrientationLandscapeLeft</string>
    <string>UIInterfaceOrientationLandscapeRight</string>
    -->
  </array>
  <!--ipad的屏幕方向设置-->
  <key>UISupportedInterfaceOrientations~ipad</key>
  <array>
    <string>UIInterfaceOrientationPortrait</string>
    <string>UIInterfaceOrientationPortraitUpsideDown</string>
    <string>UIInterfaceOrientationLandscapeLeft</string>
    <string>UIInterfaceOrientationLandscapeRight</string>
  </array>
  <key>UIViewControllerBasedStatusBarAppearance</key>
  <false/>
</dict>
</plist>

SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp]);

SystemChrome.setPreferredOrientations([DeviceOrientation.portraitDown]);

SystemChrome.setPreferredOrientations([DeviceOrientation.landscapeRight]);

SystemChrome.setPreferredOrientations([DeviceOrientation.landscapeLeft]);