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。

其他回答

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

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

最“扑”的答案如下:

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

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');
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
}

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.
}
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