我们可以在 Flutter 中检查设备是智能手机还是平板电脑？

Question

我实际上是想在我的颤振应用程序中确定该应用程序是在智能手机还是平板电脑上运行，但 device_info 包只能说明设备，而不能说明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 鲯鳅

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/

感谢@Sergi

Answer 2

如果您无权访问 BuildContext，则可以使用它。我从sdk/flutter/packages/flutter/lib/src/widgets/app.dart:1252取出来的。

  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 明确区分了手机和平板电脑，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

这里与其他 aswers 相同，但返回 enum 而不是 bool 或 String。越封闭越容易使用。

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Android，正如@Chandler 所说，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

Android Tablet 和 iPad 的宽高比（宽：高）通常在 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;
}