如何从Dart代码中检测主机平台？

Question

对于UI应该略有不同的iOS和Android,必须有检测到您正在运行哪一个的方式,但在文档我找不到它.它是什么？

Answer 1

import 'dart:io' show Platform;

if (Platform.isAndroid) {
  // Android-specific code
} else if (Platform.isIOS) {
  // iOS-specific code
}

其他选择包括:

Platform.isFuchsia
Platform.isLinux
Platform.isMacOS
Platform.isWindows
kIsWeb // A global constant indicating if the application was compiled to run on the web

文档:https://docs.flutter.io/flutter/dart-io/Platform-class.html

Answer 2

感谢Collin,最终的答案是:

bool isIOS = Theme.of(context).platform == TargetPlatform.iOS;

Answer 3

很简单，只需要导入io库

import'dart:io' show Platform;
void main(){
if(Platform.isIOS){
  return someThing();
}else if(Platform.isAndroid){
  return otherThing();
}else if(Platform.isMacOS){
  return anotherThing();
}

或以非常简单的方式

Platform.isIOS ? someThing() : anOther(),

Answer 4

if (Platform.isAndroid) {
  // Android-specific code/UI Component
} else if (Platform.isIOS) {
  // iOS-specific code/UI Component
}

不要忘记导入 IO 库。

import 'dart:io';

如果您import 'dart:html';在同一个文件中使用太多，那么您必须指定平台定义，因为两个库都有“平台”的定义

在这种情况下，请使用平台特定代码，如下所示：

import 'dart:io' as IO;
import 'dart:html';

if (IO.Platform.isAndroid) {
  // Android-specific code/UI Component
} else if (IO.Platform.isIOS) {
  // iOS-specific code/UI Component
}

如果您正在正确研究平台集成，我建议在 Flutter 站点上使用完整示例：https : //flutter.dev/docs/development/platform-integration/platform-channels

Answer 5

虽然defaultTargetPlatform会起作用,但我建议使用Theme.of(context).targetPlatform.这样可以测试iOS行为(因为defaultTargetPlatform它总是TargetPlatform.android在测试中).它还允许窗口小部件的祖先通过将其包装在Theme窗口小部件中来覆盖其目标平台.

Answer 6

对于网络和应用程序两者的更简单的方法。试试这个

import 'dart:io' show Platform;
import 'package:flutter/foundation.dart' show kIsWeb;


var platformName = '';
if (kIsWeb) {
  platformName = "Web";
} else {
  if (Platform.isAndroid) {
    platformName = "Android";
  } else if (Platform.isIOS) {
    platformName = "IOS";
  } else if (Platform.isFuchsia) {
    platformName = "Fuchsia";
  } else if (Platform.isLinux) {
    platformName = "Linux";
  } else if (Platform.isMacOS) {
    platformName = "MacOS";
  } else if (Platform.isWindows) {
    platformName = "Windows";
  }
}
print("platformName :- "+platformName.toString());

Answer 7

您可以将此扩展文件（platform_ext.dart）添加到项目中并调用任何对象

\n

import 'dart:io';\nimport 'package:flutter/foundation.dart' show kIsWeb;\n\nextension Target on Object {\n  bool isAndroid() {\n    return Platform.isAndroid;\n  } \n  bool isIOS() {\n    return Platform.isIOS;\n  } \n  bool isLinux() {\n  return Platform.isLinux;\n  } \n  bool isWindows() {\n  return Platform.isWindows; \n  }\n  bool isMacOS() {\n  return Platform.isMacOS; \n  }\n  bool isWeb() {\n  return kIsWeb; \n  }\n  // \xc2\xb7\xc2\xb7\xc2\xb7\n}\n

\n

只需导入文件并调用它

\n

   import 'platform_ext.dart';\n        ....\n        @override\n          Widget build(BuildContext context) {\n            return isAndroid()? Text("Android"):Text("Not Android");\n          }\n

\n

Answer 8

import 'dart:io' show Platform;  //at the top

String os = Platform.operatingSystem; //in your code
print(os);

Answer 9

你可以做

defaultTargetPlatform == TargetPlatform.iOS
          ? kIOSTheme
          : kDefaultTheme,

从 import 'package:flutter/foundation.dart';

Answer 10

多数“ Flutter”答案如下：

import 'package:flutter/foundation.dart' show TargetPlatform;

//...

if(Theme.of(context).platform == TargetPlatform.android)
    //do sth for Android
else if(Theme.of(context).platform == TargetPlatform.iOS)
    //do sth else for iOS
else if(Theme.of(context).platform == TargetPlatform.fuchsia)
    //even do sth else for Fuchsia OS

Answer 11

import 'dart:io' as io;

if(io.Platform.isAndroid){
 doSomething();
}else {
 doSomethingElse();
}

Answer 12

因此，这里有一个小实用程序，我用它来检测适当的反应平台和操作系统。

import'dart:io' show Platform;
import 'package:flutter/foundation.dart' show kIsWeb;

class Util {

  os getPlatform() {
    if (kIsWeb) {
      return os.Web;
    } else if (Platform.isIOS) {
      return os.IOS;
    } else if (Platform.isAndroid) {
      return os.Android;
    } else if (Platform.isFuchsia) {
      return os.Fuchsia;
    } else if (Platform.isLinux) {
      return os.Linux;
    } else if (Platform.isMacOS) {
      return os.MacOS;
    } else if (Platform.isWindows) {
      return os.Windows;
    }
    return os.Unknown;
  }

  bool isWeb() {
    return (getPlatform()==os.Web);
  }

  bool isMobile() {
    os platform = getPlatform();
    return (platform == os.Android || platform == os.IOS || platform== os.Fuchsia);
  }

  bool isComputer() {
    os platform = getPlatform();
    return (platform == os.Linux || platform == os.MacOS || platform== os.Windows);
  }

}

enum os { Unknown, Web, Android, Fuchsia, IOS, Linux, MacOS, Windows }

Answer 13

您可以使用通用平台包：

https://pub.dev/packages/universal_platform

import 'package:universal_platform/universal_platform.dart';

bool isIos = UniversalPlatform.isIOS;
bool isAndroid = UniversalPlatform.isAndroid;
bool isWeb = UniversalPlatform.isWeb;
print('iOS: $isIos');
print('Android: $isAndroid');
print('Web: $isWeb');

Answer 14

import 'dart:io' show Platform;

if (Platform.isAndroid) {
  // Android-specific code
} else if (Platform.isIOS) {
  // iOS-specific code
}else if (Platform.isFuchsia) {
  // Fuchsia-specific code
}else if (Platform.isLinux) {
  // Linux-specific code
}else if (Platform.isMacOS) {
  // MacOS-specific code
}else if (Platform.isWindows) {
  // Windows-specific code
}else if (Platform.isWindows) {
  // Windows-specific code
}

用于网络

import 'package:flutter/foundation.dart' show kIsWeb;

if (kIsWeb) {
  // running on the web!
} else {
  // NOT running on the web! You can check for additional platforms here.
}