flutter - 我们可以在 Flutter 中检查设备是智能手机还是平板电脑？

Question

我实际上是想弄清楚应用程序是否在我的颤振应用程序中的智能手机或平板电脑上运行，但是包device_info只能说明设备，而不能说明该设备是智能手机还是平板电脑。有没有办法通过检查设备的大小来做到这一点？

非常感谢马希

Answer 1

// The equivalent of the "smallestWidth" qualifier on Android.
var shortestSide = MediaQuery.of(context).size.shortestSide;

// Determine if we should use mobile layout or not, 600 here is
// a common breakpoint for a typical 7-inch tablet.
final bool useMobileLayout = shortestSide < 600;

复制自https://flutter.rocks/2018/01/28/implementing-adaptive-master-detail-layouts/

谢谢@Sergi

Answer 2

如果您无权访问 BuildContext，则可以使用它。我把它从sdk/flutter/packages/flutter/lib/src/widgets/app.dart:1252.

  String getDeviceType() {
    final data = MediaQueryData.fromWindow(WidgetsBinding.instance.window);
    return data.size.shortestSide < 600 ? 'phone' :'tablet';
  }

Answer 3

其中一种方法是计算屏幕分辨率的对角线。

import 'package:flutter/widgets.dart';
import 'dart:math';

class TabletDetector {

  // iPhone 6S 
  // |_ [portrait]
  //    |_ size: 375.0x667.0, pixelRatio: 2.0, pixels: 750.0x1334.0
  //       |_ diagonal: 765.1888655750291
  // |_ [horizontal]
  //    |_ size: 667.0x375.0, pixelRatio: 2.0, pixels: 1334.0x750.0
  //       |_ diagonal: 765.1888655750291

  // iPhone X 
  // |_ [portrait]
  //    |_ size: 375.0x812.0, pixelRatio: 3.0, pixels: 1125.0x2436.0
  //       |_ diagonal: 894.4098613052072
  // |_ [horizontal]
  //    |_ size: 812.0x375.0, pixelRatio: 3.0, pixels: 2436.0x1125.0
  //       |_ diagonal: 894.4098613052072

  // iPhone XS Max 
  // |_ [portrait]
  //    |_ size: 414.0x896.0, pixelRatio: 3.0, pixels: 1242.0x2688.0
  //       |_ diagonal: 987.0217829409845
  // |_ [horizontal]
  //    |_ size: 896.0x414.0, pixelRatio: 3.0, pixels: 2688.0x1242.0
  //       |_ diagonal: 987.0217829409845

  // iPad Pro (9.7-inch) 
  // |_ [portrait]
  //    |_ size: 768.0x1024.0, pixelRatio: 2.0, pixels: 1536.0x2048.0
  //       |_ diagonal: 1280.0
  // |_ [horizontal]
  //    |_ size: 1024.0x768.0, pixelRatio: 2.0, pixels: 2048.0x1536.0
  //       |_ diagonal: 1280.0

  // iPad Pro (10.5-inch) 
  // |_ [portrait]
  //    |_ size: 834.0x1112.0, pixelRatio: 2.0, pixels: 1668.0x2224.0
  //       |_ diagonal: 1390.0
  // |_ [horizontal]
  //    |_ size: 1112.0x834.0, pixelRatio: 2.0, pixels: 2224.0x1668.0
  //       |_ diagonal: 1390.0

  // iPad Pro (12.9-inch) 
  // |_ [portrait]
  //    |_ size: 1024.0x1366.0, pixelRatio: 2.0, pixels: 2048.0x2732.0
  //       |_ diagonal: 1707.2000468603555
  // |_ [horizontal]
  //    |_ size: 1366.0x1024.0, pixelRatio: 2.0, pixels: 2732.0x2048.0
  //       |_ diagonal: 1707.2000468603555

  static bool isTablet(MediaQueryData query) {
    var size = query.size;
    var diagonal = sqrt(
      (size.width * size.width) + 
      (size.height * size.height)
    );

    /*
    print(
      'size: ${size.width}x${size.height}\n'
      'pixelRatio: ${query.devicePixelRatio}\n'
      'pixels: ${size.width * query.devicePixelRatio}x${size.height * query.devicePixelRatio}\n'
      'diagonal: $diagonal'
    );
    */

    var isTablet = diagonal > 1100.0;
    return isTablet;
  }
}

Answer 4

尽管 iOS 在手机和平​​板电脑之间有明确的区别，但在 Android 中不会发生这种情况。您需要根据屏幕宽度进行选择。

查看这篇文章以查看有关如何区分的示例：https ://flutter.rocks/2018/01/28/implementing-adaptive-master-detail-layouts/

Answer 5

这与其他 aswers 相同，但返回的enum是 a 而不是 abool或 a String。由于它更封闭，因此更易于使用。

import 'package:flutter/widgets.dart';

enum DeviceType { Phone, Tablet }

DeviceType getDeviceType() {
  final data = MediaQueryData.fromWindow(WidgetsBinding.instance.window);
  return data.size.shortestSide < 550 ? DeviceType.Phone : DeviceType.Tablet;
}

感谢@Chandler 和@bakua 的启发:·)

Answer 6

对于@Chandler 所说的Android，您应该检查屏幕的最小尺寸，但对于iOS，您可以使用device_info包以100％的准确度识别它是否是iPad：

添加pubspec.yaml：

device_info: ^0.4.2+4

  static Future<bool> isTablet(BuildContext context) async {

    if (Platform.isIOS) {
      DeviceInfoPlugin deviceInfo = DeviceInfoPlugin();
      IosDeviceInfo iosInfo = await deviceInfo.iosInfo;

      return iosInfo.model.toLowerCase() == "ipad";
    } else {
      // The equivalent of the "smallestWidth" qualifier on Android.
      var shortestSide = MediaQuery.of(context).size.shortestSide;

      // Determine if we should use mobile layout or not, 600 here is
      // a common breakpoint for a typical 7-inch tablet.
      return shortestSide > 600;
    }
  }

Answer 7

通常安卓平板和 iPad 的宽高比（宽：高）在 0.75 ~ 1.4 的范围内，以下是最快的检查方法。我们可以根据Aspect ratio来调整UI。

bool isTablet;
double ratio = MediaQuery.of(context).size.width / MediaQuery.of(context).size.height;
if( (ratio >= 0.74) && (ratio < 1.5) )
{
  isTablet = true;
} else{
  isTablet = false;
}