如何从Dart代码中检测主机平台?

对于在iOS和Android上略有不同的UI，即在不同的平台上，必须有一种方法来检测应用程序在哪个平台上运行，但我在文档中找不到它。是什么?

当前回答

您可以将此扩展添加到项目中

import 'package:flutter/material.dart';

extension PlatformExtension on BuildContext {
  bool get isMobile =>
      Theme.of(this).platform == TargetPlatform.iOS ||
      Theme.of(this).platform == TargetPlatform.android;

  bool get isDesktop =>
      Theme.of(this).platform == TargetPlatform.macOS ||
      Theme.of(this).platform == TargetPlatform.windows ||
      Theme.of(this).platform == TargetPlatform.linux;
}

extension TargetPlatformExtension on TargetPlatform {
  bool get isMobile =>
      this == TargetPlatform.iOS || this == TargetPlatform.android;

  bool get isDesktop =>
      this == TargetPlatform.linux ||
      this == TargetPlatform.macOS ||
      this == TargetPlatform.windows;
}

现在您可以使用。

内置context => context.isDesktop 目标平台=> defaulttarded平台

建议从上下文访问平台。

要检测您的应用程序是否在浏览器上运行，您可以轻松地使用基础库中的kIsWeb常量。

import 'package:flutter/foundation.dart';

  log('$kIsWeb'); // will print true if the app is running on a browser

注意，如果你在桌面上运行web应用程序，isDesktop getter将返回true，对于移动平台也是如此。为了避免这种情况。

import 'package:flutter/foundation.dart';

  if (!kIsWeb && defaultTargetPlatform.isDesktop) {
    // do stuff for desktop apps only
  }

  if (!kIsWeb && defaultTargetPlatform.isMobile) {
    // do stuff for mobile apps only
  }

您可以修改扩展以获得您喜欢的实现。

2022-11-14 15:20:51

其他回答

import 'dart:io' show Platform;

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

所有选项包括:

Platform.isAndroid
Platform.isFuchsia
Platform.isIOS
Platform.isLinux
Platform.isMacOS
Platform.isWindows

你也可以使用kIsWeb来检测你是否在web上运行，kIsWeb是一个全局常量，指示应用程序是否被编译为在web上运行:

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.
}

平台文档:https://api.flutter.dev/flutter/dart-io/Platform-class.html kIsWeb文档:https://api.flutter.dev/flutter/foundation/kIsWeb-constant.html

2018-06-07 15:02:05

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';

如果你使用导入'dart:html';那么你必须指定平台定义，因为两个库都有“平台”的定义

在这种情况下，使用如下所示的平台特定代码:

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
}

如果你正在寻找合适的平台集成，我建议在Flutter网站上使用完整的示例: https://flutter.dev/docs/development/platform-integration/platform-channels

2021-02-09 04:45:41

这个自定义创建的类将帮助您检测平台:

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

enum Os {
  web,
  android,
  ios,
  macOS,
  linux,
  windows,
  fuchsia,
}

class Platform {
  const Platform();

  /// Platform is Web.
  static bool get isWeb => os == Os.web;

  /// Platform is Android.
  static bool get isAndroid => os == Os.android;

  /// Platform is IOS.
  static bool get isIOS => os == Os.ios;

  /// Platform is Fuchsia.
  static bool get isFuchsia => os == Os.fuchsia;

  /// Platform is Linux.
  static bool get isLinux => os == Os.linux;

  /// Platform is MacOS.
  static bool get isMacOS => os == Os.macOS;

  /// Platform is Windows.
  static bool get isWindows => os == Os.windows;

  /// Platform is Android or IOS.
  static bool get isMobile => isAndroid || isIOS;

  /// Platform is Android or IOS or Fuchsia.
  static bool get isFullMobile => isMobile || isFuchsia;

  /// Platform is Linux or Windows or MacOS.
  static bool get isDesktop => isLinux || isWindows || isMacOS;

  /// Getting the os name.
  static Os get os {
    if (kIsWeb) {
      return Os.web;
    }
    switch (defaultTargetPlatform) {
      case TargetPlatform.android:
        return Os.android;
      case TargetPlatform.iOS:
        return Os.ios;
      case TargetPlatform.macOS:
        return Os.macOS;
      case TargetPlatform.windows:
        return Os.windows;
      case TargetPlatform.fuchsia:
        return Os.fuchsia;
      case TargetPlatform.linux:
        return Os.linux;
    }
  }
}

2023-01-29 10:59:51

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

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

extension Target on Object {
  bool isAndroid() {
    return Platform.isAndroid;
  } 
  bool isIOS() {
    return Platform.isIOS;
  } 
  bool isLinux() {
  return Platform.isLinux;
  } 
  bool isWindows() {
  return Platform.isWindows; 
  }
  bool isMacOS() {
  return Platform.isMacOS; 
  }
  bool isWeb() {
  return kIsWeb; 
  }
  // ···
}

只需导入文件并调用它

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

2021-08-27 13:05:29