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关于Android模拟器无法连接网络

Tue, 03 Jun 2025 13:55:08 +0000

一个很奇怪的问题，在模拟器测试安卓应用是总是显示

1Post "https://xxx": EOF

但偶尔又变得正常，通过一番查找，原来是设置 Android Studio 使用代理之后，通过其创建的模拟器也会默认使用代理。解决方式也很简单，只要打开模拟器设置然后取消代理即可

Flutter实现本地化多语言

Wed, 02 Oct 2024 13:12:27 +0000

内置组件本地化

添加依赖

Flutter默认组件的本地化只需要添加

1flutter_localizations:
2  sdk: flutter

使用命令行添加就是

1flutter pub add flutter_localizations --sdk=flutter

修改入口组件 main.dart

1import 'package:flutter_localizations/flutter_localizations.dart';

 1return const MaterialApp(
 2  title: 'Localizations Sample App',
 3  localizationsDelegates: [
 4    GlobalMaterialLocalizations.delegate,
 5    GlobalWidgetsLocalizations.delegate,
 6    GlobalCupertinoLocalizations.delegate,
 7  ],
 8  supportedLocales: [
 9    Locale('en'), // English
10    Locale('zh'), // Chinese
11  ],
12  home: MyHomePage(),
13);

这样Flutter内置组件所显示的语言就能和系统语言保持一致，如果想要手动修改，只需要添加参数

1return const MaterialApp(
2  ...
3  locale: Locale("zh"),
4);

如果想要修改指定的组件，需要使用到 Localizations.override

 1Widget build(BuildContext context) {
 2  return Scaffold(
 3    appBar: AppBar(
 4      title: Text(widget.title),
 5    ),
 6    body: Center(
 7      child: Column(
 8        mainAxisAlignment: MainAxisAlignment.center,
 9        children: <Widget>[
10          Localizations.override(
11            context: context,
12            locale: const Locale('zh'),
13            child: Builder(
14              builder: (context) {
15                return CalendarDatePicker(
16                  initialDate: DateTime.now(),
17                  firstDate: DateTime(1900),
18                  lastDate: DateTime(2100),
19                  onDateChanged: (value) {},
20                );
21              },
22            ),
23          ),
24        ],
25      ),
26    ),
27  );
28}

自定义本地化

根据官方文档，可以利用 flutter_localozations 和 intl 来实现。但是如果根据官方文档，那可不是一般的麻烦，而是相当麻烦，操作步骤包括但不限于

修改 pubsepc.yaml
添加 l10n.yaml
添加 .arb 文件

当然，这一切也不能说是很麻烦，毕竟只要第一次改好，后续只用修改 .arb 文件就能自动运行，但根据这个流程生成的多语言本地化，我觉得有几个问题：

自动生成的 .dart 文件是保存在 {项目目录}/.dart_tool/flutter_gen/gen_l10n 目录下的，这会导致项目默认的代码没有多语言相关，只有一些不知所谓的 .arb 文件，毕竟与多语言相关的代码都是自动生成的
也是最重要的一点，我为什么要在默认语言下重复定义一个不能带空格，只允许定义符合 dart方法名称 的关键字以供调用，比如一个简单的字符串
```
1Text("Hello World")
```
我必须在默认语言定义一个
```
1// app_es.arb
2"helloWorld": "Hello World"
```
然后在其它语言定义
```
1// app_zh.arb
2"helloWorld": "你好 世界"
```
最后再修改默认的调用
```
1Text(AppLocations.of(context).helloWorld)
```
我为什么不能直接使用原有的字符串呢，这样就不用再为默认的语言添加额外的翻译，比如
```
1Text(AppLocations.of(context).tr("Hello World"))
```

所以，我仔细研究了一下，大抵不用如此麻烦

自定义本地化(非代码自动生成)

首先添加 l10n.dart

 1import 'dart:async';
 2
 3import 'package:flutter/foundation.dart';
 4import 'package:flutter/widgets.dart';
 5import 'package:flutter_localizations/flutter_localizations.dart';
 6import 'package:intl/intl.dart' as intl;
 7
 8import 'l10n_en.dart';
 9import 'l10n_zh.dart';
10
11abstract class L10n {
12  L10n(String locale)
13  : localeName = intl.Intl.canonicalizedLocale(locale.toString());
14
15  final String localeName;
16
17  static L10n? of(BuildContext context) {
18    return Localizations.of<L10n>(context, L10n);
19  }
20
21  static const LocalizationsDelegate<L10n> delegate = _L10nDelegate();
22
23  static const List<LocalizationsDelegate<dynamic>> localizationsDelegates =
24  <LocalizationsDelegate<dynamic>>[
25    delegate,
26    GlobalMaterialLocalizations.delegate,
27    GlobalCupertinoLocalizations.delegate,
28    GlobalWidgetsLocalizations.delegate,
29  ];
30
31  static const List<Locale> supportedLocales = <Locale>[
32    Locale('en'),
33    Locale('zh')
34  ];
35
36  String tr(String key);
37}
38
39class _L10nDelegate extends LocalizationsDelegate<L10n> {
40  const _L10nDelegate();
41
42  @override
43  Future<L10n> load(Locale locale) {
44    return SynchronousFuture<L10n>(lookupL10n(locale));
45  }
46
47  @override
48  bool isSupported(Locale locale) =>
49  <String>['en', 'zh'].contains(locale.languageCode);
50
51  @override
52  bool shouldReload(_L10nDelegate old) => false;
53}
54
55L10n lookupL10n(Locale locale) {
56  // Lookup logic when only language code is specified.
57  switch (locale.languageCode) {
58    case 'en':
59    return L10nEn();
60    case 'zh':
61    return L10nZh();
62  }
63
64  throw FlutterError(
65    'L10n.delegate failed to load unsupported locale "$locale". This is likely '
66    'an issue with the localizations generation tool. Please file an issue '
67    'on GitHub with a reproducible sample app and the gen-l10n configuration '
68    'that was used.');
69}

上述代码其实是由根据官方文档自动生成的 .dart 文件转化而来

添加默认语言的翻译

 1// l10n_en.dart
 2import 'l10n.dart';
 3
 4class L10nEn extends L10n {
 5  L10nEn([String locale = 'en']) : super(locale);
 6
 7  @override
 8  String tr(String key) {
 9    return translations[key] ?? key;
10  }
11}
12
13const translations = {};

对的，你没有看错， translations 甚至可以是空的，这样就不用重复定义默认语言的翻译

添加其它语言的翻译

 1// l10n_zh.dart
 2import 'l10n.dart';
 3
 4class L10nZh extends L10n {
 5  L10nZh([String locale = 'zh']) : super(locale);
 6
 7  @override
 8  String tr(String key) {
 9    return translations[key] ?? key;
10  }
11}
12
13const translations = {
14  "Settings": "设置",
15  "Basic Settings": "基础设置",
16  "Theme": "主题",
17  "Language": "语言",
18  "About": "关于",
19  "Help": "帮助",
20};

修改 main.dart 入口组件

1import 'app/l10n/l10n.dart';
2
3return const MaterialApp(
4  title: 'Localizations Sample App',
5  localizationsDelegates: L10n.localizationsDelegates,
6  supportedLocales: L10n.supportedLocales,
7  home: MyHomePage(),
8);

这样就能使用自定义的翻译了

本地化多语言的使用

最常用的是在 Text 组件里

1Text(L10n.of(context)!.tr("Hello World"))

但是所有的字符都要添加 L10n.of(context)! 未免有些麻烦，所以我增加了自定义扩展

BuildContext

1extension L10nContext on BuildContext {
2  String tr(String key) {
3    final t = L10n.of(this);
4    if (t == null) {
5      return key;
6    }
7    return t.tr(key);
8  }
9}

使用方式

1Text(context.tr("Hello World"))

String

1extension L10nString on String {
2  String tr(BuildContext context) {
3    final t = L10n.of(context);
4    if (t == null) {
5      return this;
6    }
7    return t.tr(this);
8  }
9}

使用方式

1Text("Hello World".tr(context))

Text

 1extension L10nText on Text {
 2  Text tr(BuildContext context) {
 3    final t = L10n.of(context);
 4    if (t == null || data == null) {
 5      return this;
 6    }
 7    return Text(t.tr(data ?? ''),
 8      key: key,
 9      style: style,
10      strutStyle: strutStyle,
11      textAlign: textAlign,
12      textDirection: textDirection,
13      locale: locale,
14      softWrap: softWrap,
15      overflow: overflow,
16      textScaler: textScaler,
17      maxLines: maxLines,
18      semanticsLabel: semanticsLabel,
19      textWidthBasis: textWidthBasis);
20  }
21}

使用方式

1Text("Hello World").tr(context)

如此，就能最大限度的较少对原有代码的侵略性修改

优化多语言选择

我这里选用的是 riverpod 进行状态管理，首先定义一个本地语言的状态

1final localeProvider = StateProvider<String>((ref) {
2  return "zh";
3});

接着修改 main.dart

 1class MyApp extends ConsumerWidget {
 2  const MyApp({super.key});
 3
 4  @override
 5  Widget build(BuildContext context, WidgetRef ref) {
 6    final localeCode = ref.watch(localeProvider);
 7
 8    return MaterialApp(
 9      locale: L10n.delegate.isSupported(localeCode) ? Locale(localeCode) : null,
10      ...
11    );
12  }
13}

这样就能很方便地修改应用的显示语言

1ref.read(localeProvider.notifier).state = "zh";

参考文档

使用Go重写MetingJS的API

Tue, 26 Dec 2023 13:23:00 +0000

MetingJS 是一款通过获取网易云音乐或者QQ音乐等服务的歌单、歌手、歌曲、歌词等信息，然后使用开源HTML5播放器 APlayer 进行播放的插件。而 MetingJS 是一段很小的JS代码，它提供了一个默认的API接口：https://api.i-meto.com/meting/api , 但很不幸，该接口偶尔会出问题，作者也很久没有回复issue了。

现在也有一个开源的 injahow/meting-api，该服务同样使用PHP编写，我不太懂PHP，我只是想要设置一个缓存，来缓存所有的歌曲信息，而不仅仅是歌单列表，另外是可以支持内存缓存和本地磁盘缓存，而不是直接从本地文件中读取。

基于此，与其自己改不是太懂的PHP，说不定会出现一些意想不到的漏洞(源自某安全公司多次CTF换来的教训)，不如使用熟悉的Go重写实现，毕竟核心代码也不是太多

功能

支持网易云音乐，QQ音乐
支持新服务接口扩展
支持所有请求结果的缓存
更方便的配置(环境变量+配置文件)，而不用修改源文件
基于 Go 编写，一次编译，到处运行

使用

手动部署

下载仓库

1git clone https://github.com/honmaple/meting-api

编译可执行文件
```
1go mod download
2go build -o meting-api .
```
或者使用 Docker 进行编译, 编译后的文件在 /usr/bin/meting-api
```
1docker build -t meting-api .
```
运行
```
1./meting-api -D
```

Docker部署

1docker run --name meting-api --restart=always -d -p 8000:8000 -v /tmp/meting-cache:/opt/meting-api/cache honmaple/meting-api

配置说明

配置可以使用环境变量或者配置文件设置

环境变量: 使用 METING_XXXX, 比如 METING_CACHE_TTL
配置文件: 默认使用当前目录下的 config.yaml, 如果使用 Docker 部署，需要文件挂载到 /opt/meting-api/config.yaml

具体配置:

 1# 缓存过期时间
 2cache.ttl:                  3600
 3# 缓存路径，设置为空是禁用缓存
 4cache.path:                 "./cache"
 5# 是否激活缓存
 6cache.enabled:              true
 7
 8# 服务监听地址，:8000 表示监听 0.0.0.0:8000
 9server.addr:                ":8000"
10# 对外服务地址，比如 https://api.xxxx.com/meting
11server.host:                ""
12
13## cors设置
14server.cors.allow_headers:
15  - "*"
16server.cors.allow_origins:
17  - "*"
18server.cors.allow_methods:
19  - "*"
20
21# 日志相关, out可选stdout,stderr,file，或者使用|分隔多个，比如stderr|file
22logger.out:                 "stdout"
23# 日志级别
24logger.level:               "info"
25# 日志文件名格式
26logger.file_format:         "%Y%m%d"
27# 日志文件保留数量
28logger.file_rotation_count: 3

命令行参数

查看支持的服务
```
1./meting-api --list
```

指定监听地址

1./meting-api -a :8001
2./meting-api --addr :8001

显示请求记录
```
1./meting-api -D
2./meting-api --debug
```

指定配置文件

1./meting-api -c /etc/meting.yaml
2./meting-api --config /etc/meting.yaml

显示当前配置
```
1./meting-api config
```

删除指定缓存

1./meting-api delete-cache 'server:netease:type:${type}:id:${id}'

网页端设置

其中 http://localhost:8000/ 是对外服务的接口

 1<meting-js
 2  server="netease"
 3  type="artist"
 4  id="6452">
 5</meting-js>
 6<script type="text/javascript">
 7  var meting_api='http://localhost:8000/?server=:server&type=:type&id=:id&auth=:auth&r=:r';
 8</script>
 9<script src="https://cdn.jsdelivr.net/npm/aplayer/dist/APlayer.min.js"></script>
10<script src="https://cdn.jsdelivr.net/npm/meting@2/dist/Meting.min.js"></script>

演示

基于Quasar实现一个树状选择器TreeSelect

Tue, 09 May 2023 23:23:52 +0000

Quasar 默认没有树状选择器的支持，而在 Vue 中通常会使用一个现成的vue-treeselect, 这是一个非常不错的 Select 组件, 此次不使用该组件，而是利用 Quasar 中的 q-select 和 q-tree 结合，实现一个类似的树状选择器

源数据结构

 1{
 2    "id": 1,
 3    "name": "admin",
 4    "desc": "管理员",
 5    "children": [{
 6        "id": 6,
 7        "name": "superadmin",
 8        "desc": "超级管理员",
 9        "children": [{
10            "id": 10,
11            "name": "vvvvv",
12            "desc": "dddd",
13        }]
14    }]
15}

组件模版

 1<template>
 2  <q-select dense outlined
 3            emit-value map-options
 4            option-value="id"
 5            option-label="name"
 6            label="角色列表"
 7            :options="list"
 8            :loading="table.loading"
 9            :multiple="multiple"
10            :use-chips="multiple"
11            @filter="filterFn"
12            :model-value="modelValue"
13            @update:model-value="value => $emit('update:modelValue', value)" >
14    <template v-slot:option="{ itemProps, opt, selected, toggleOption }">
15      <q-tree :nodes="[opt]"
16              node-key="id"
17              label-key="name"
18              :tick-strategy="multiple?'strict':'none'"
19              v-model:ticked="table.ticked"
20              v-model:selected="table.selected"
21              v-if="opt.parent_id == 0">
22        <template v-slot:default-header="prop">
23          <div class="items-center">
24            {{ prop.node.desc }}({{ prop.node.name }})
25          </div>
26        </template>
27      </q-tree>
28    </template>
29  </q-select>
30</template>

这里利用 slot 方式添加 q-tree 组件, 由于只能传递单个选项(option), 所以在传递给 q-tree 的参数 nodes 需要修改成 [opt]。

而在 q-tree 中，单选和多选同样有区别，单选所使用的参数为 v-model:ticked, 点击选项即可选中，多选所使用的参数为 v-model:selected, 配置为多选状态时每个树状列表选项前会添加一个 checkbox，多选状态需要配置 tick-strategy 参数

strict: 父选项和子选项的选中状态相互独立
leaf: 选中父选项同时选中父选项下的子选项
none: 禁用多选

组件选项

 1const props = defineProps({
 2    multiple: {
 3        type: Boolean,
 4        default: false,
 5    },
 6    modelValue: {
 7        default: null,
 8        required: true,
 9    },
10})

父组件可以使用

1<role-select multiple v-model="form.roles"></role-select>

同时，为了区分多选和单选, 需要将没有用到的选项设置为 undefined, 同时监听选项的修改

 1const emit = defineEmits(['update:model-value'])
 2const { modelValue, multiple } = toRefs(props)
 3
 4if (multiple.value) {
 5    table.value.selected = undefined
 6
 7    watch(() => table.value.ticked, (val) => {
 8        emit('update:model-value', val)
 9    })
10
11} else {
12    table.value.ticked = undefined
13
14    watch(() => table.value.selected, (val) => {
15        emit('update:model-value', val)
16    })
17}

为了让子选项在选中状态时也能够显示 .name，而不是 .id，需要遍历所有选项，将其合成一个列表，在 q-tree 组件中通过判断 row.parent_id 只显示父组件, 这里也可以通过定义 q-select 的 selected 或者是 selected-item 插槽来显示正确的名称

 1function makeRows(rows) {
 2    if (!rows) {
 3        return []
 4    }
 5    let newRows = []
 6    rows.forEach(row => {
 7        newRows.push(row)
 8        if (row.children && row.children.length > 0) {
 9            newRows = newRows.concat(makeRows(row.children))
10        }
11    })
12    return newRows
13}
14
15const list = computed(() => {
16    return makeRows(table.value.list)
17})

最后就是从后端获取列表数据

 1const table = ref({
 2    list: [],
 3    ticked: [],
 4    expanded: [],
 5    selected: [],
 6    loading: false,
 7})
 8
 9const handleFetch = (props) => {
10    ...
11    table.value.loading = true
12    return api.fetchList(query).then(response => {
13        table.value.list = response.data.list
14    }).finally(() => {
15        table.value.loading = false
16    })
17}
18
19const filterFn = (val, update, abort) => {
20    if (table.value.list && table.value.list.length > 0) {
21        update()
22        return
23    }
24    update(() => {handleFetch()})
25}

最终实现

基于Quasar实现一个树状表格TableTree

Sat, 29 Apr 2023 00:03:40 +0000

Quasar 是一个基于 Vue3 的前端UI框架，使用的是 Material Design, 对于国内而言(包括我)觉得确实不太好看，但因为之前使用的是 Element-UI，大概是由于审美疲劳，此次升级我的后台管理UI，没有继续使用 Vue3 版本的 Element-Plus。不久前我也是基于 Quasar 开发了一个 Memos 客户端, 感觉效果还不错

前言

Quasar 默认没有树状表格的支持，但我觉得树状表格其实还挺重要的，尤其是在显示一些树状的数据，比如一个部门列表(打比方), 树状表格能够清晰的表明各部门之间的上下关系，目前我看实现树状表格的示例要么是基于 qhierarchy (使用 q-markup-table 实现，定制太困难), 要么就是实现方式太复杂 tree-table-example, 所以我研究了一下，发现其实还挺简单的，故此记录

实现一(废弃)

虽然 Quasar 没有树状表格的组件, 但 q-table 默认是支持 Expanding rows 的，所以我一开始的想法是使用这个功能实现一个递归的组件, 就像这样

 1<template>
 2  <q-tr :key="row.id" :props="props">
 3    <slot :row="row" :status="status" :indent="indent" :indentStyle="indentStyle(indent)"></slot>
 4  </q-tr>
 5  <template :key="index" v-for="(child, index) in row.children" v-if="status.expand">
 6    <table-tree :props="props" :indent="indent + 1" :row="child" v-slot="scope">
 7      <slot :row="scope.row" :status="scope.status" :indent="scope.indent" :indentStyle="indentStyle(scope.indent)"></slot>
 8    </table-tree>
 9  </template>
10</template>

而在父组件中调用只需要把原来的 props 改成 scope

 1<template v-slot:body="props">
 2  <table-tree :props="props" :row="props.row" v-slot="scope">
 3    <q-td auto-width>
 4      <q-checkbox size="sm" v-model="scope.status.selected" />
 5    </q-td>
 6    <q-td>
 7      <q-btn flat round dense size="xs"
 8             :icon="scope.status.expand ? 'remove' : 'add'"
 9             @click="scope.status.expand = !scope.status.expand"
10             v-if="scope.row.children && scope.row.children.length > 0" />
11      {{ scope.row.name }}
12    </q-td>
13    <q-td>{{ scope.row.desc }}</q-td>
14  </table-tree>
15</template>

但是后面发现表格在多选状态下无法和原有的表格选择进行联动，只能自己实现选中和取消选中的方法，虽然也能实现，当很麻烦，只好另寻其它方式

实现二

后面研究了一下 Fernando2684 的实现方式, 虽然他的方式同样复杂，当实现原理其实很简单, 那就是修改原始数据，比如第二行需要进行展开，那我就在原来第二行的数据下把第二行的子数据追加上去，取消展开就把子数据删除，恢复原来的数据。有了这个原理后就好办了，我们可以利用 Expanding rows 时用到的 props.expand 参数来控制是否展开子数据, 然后利用计算属性动态的计算展开后的数据

表格模版

 1<q-table flat bordered
 2         row-key="id"
 3         separator="cell"
 4         selection="multiple"
 5         - :rows="table.list"
 6         + :rows="expandRows"
 7         v-model:expanded="table.expanded"
 8         v-model:selected="table.selected"
 9         v-model:pagination="table.pagination">
10  <template v-slot:body="props">
11    <q-tr :props="props">
12      <q-td auto-width>
13        <q-checkbox size="sm" v-model="props.selected" />
14      </q-td>
15      <q-td>
16        <q-btn flat round dense size="xs"
17               :icon="props.expand ? 'remove' : 'add'"
18               @click="props.expand = !props.expand"
19               v-if="props.row.children && props.row.children.length > 0" />
20        {{ props.row.name }}
21      </q-td>
22      <q-td>{{ props.row.desc }}</q-td>
23    </q-tr>
24  </template>
25</q-table>

表格数据

 1const table = ref({
 2    list: [],
 3    expanded: [],
 4    selected: [],
 5    loading: true,
 6    pagination: {
 7        page: 1,
 8        sortBy: 'desc',
 9        descending: false,
10        rowsPerPage: 0,
11        rowsNumber: 0,
12    }
13})
14
15const expandRows = computed(() => {
16    return makeRows(table.value.list, table.value.expanded)
17})

这里提一嘴，pagination.rowsPerPage 默认最好设置为0(不限制每页的数量, 但会由由后端控制返回的行数), 否则展开子数据后的数据会被放到第二页, 影响数据查看

动态计算展开后的数据

 1function makeRows(rows, expanded) {
 2    if (!rows) {
 3        return []
 4    }
 5    if (expanded.length == 0) {
 6        return rows
 7    }
 8    let newRows = []
 9    rows.forEach(row => {
10        newRows.push(row)
11        if (expanded.indexOf(row.id) > -1) {
12            newRows = newRows.concat(makeRows(row.children, expanded))
13        }
14    })
15    return newRows
16}

注意，这里因为要递归计算多级子目录，所以不能直接在 setup 上直接用 const 定义

缩进：~~目前缩进确实有些问题，其中一个解决办法是原始数据会带有 parent_id 字段，可以通过判断 parent_id 大于0时增加缩进~~

缩进的计算可以通过makeRows函数在遍历时添加每行数据的层级

 1function makeRows(rows, expanded, indent) {
 2    if (!rows) {
 3        return []
 4    }
 5    let newRows = []
 6    rows.forEach(row => {
 7        row._indent = indent
 8        newRows.push(row)
 9        if (expanded.indexOf(row.id) > -1) {
10            newRows = newRows.concat(makeRows(row.children, expanded, indent + 1))
11        }
12    })
13    return newRows
14}
15
16export default function useTable(table) {
17    const expandRows = computed(() => {
18        return makeRows(table.value.list, table.value.expanded, 0)
19    })
20    return {
21        expandRows,
22    }
23}

然后在表格中添加对应的偏移即可, 需要注意的是表格对齐方向需要设置为 left (默认值)

1<template v-slot:body-cell-name="props">
2  <q-td :props="props" :style="'padding-left:' + ((props.row._indent || 0) + 1) + 'rem'">
3    <q-btn flat round dense size="xs"
4           :icon="props.expand ? 'remove' : 'add'"
5           @click="props.expand = !props.expand"
6           v-if="props.row.children && props.row.children.length > 0" />
7    {{ props.row.name }}
8  </q-td>
9</template>

最终实现

flutter笔记之初体验

Sat, 05 Jun 2021 22:58:01 +0000

安装

安装flutter

首先下载flutter包, 解压到 ~/repo 目录,并配置 ~/.bashrc
```
1export PATH=$PATH:$HOME/repo/flutter/bin
```

source ~/.bashrc使其生效

注意：首次运行flutter，macos可能会提示无法打开dart，需要到 系统偏好 -> 安全性与隐私 点击允许

1└──╼ flutter --version
2Flutter 2.2.1 • channel stable • https://github.com/flutter/flutter.git
3Framework • revision 02c026b03c (9 天前) • 2021-05-27 12:24:44 -0700
4Engine • revision 0fdb562ac8
5Tools • Dart 2.13.1

第一步，禁用 google analytics

 1└──╼ flutter config --no-analytics
 2
 3  ╔════════════════════════════════════════════════════════════════════════════╗
 4  ║                 Welcome to Flutter! - https://flutter.dev                  ║
 5  ║                                                                            ║
 6  ║ The Flutter tool uses Google Analytics to anonymously report feature usage ║
 7  ║ statistics and basic crash reports. This data is used to help improve      ║
 8  ......
 9  ║ See Google's privacy policy:                                               ║
10  ║ https://policies.google.com/privacy                                        ║
11  ╚════════════════════════════════════════════════════════════════════════════╝
12
13Analytics reporting disabled.
14
15You may need to restart any open editors for them to read new settings.

第二步, 执行 flutter doctor 检查依赖环境

 1└──╼ flutter doctor
 2Running "flutter pub get" in flutter_tools...                      10.6s
 3Doctor summary (to see all details, run flutter doctor -v):
 4[✓] Flutter (Channel stable, 2.2.1, on macOS 11.3.1 20E241 darwin-x64, locale zh-Hans-CN)
 5[✗] Android toolchain - develop for Android devices
 6    ✗ Unable to locate Android SDK.
 7      Install Android Studio from: https://developer.android.com/studio/index.html
 8      On first launch it will assist you in installing the Android SDK components.
 9      (or visit https://flutter.dev/docs/get-started/install/macos#android-setup for detailed instructions).
10      If the Android SDK has been installed to a custom location, please use
11      `flutter config --android-sdk` to update to that location.
12
13[✗] Xcode - develop for iOS and macOS
14    ✗ Xcode installation is incomplete; a full installation is necessary for iOS development.
15      Download at: https://developer.apple.com/xcode/download/
16      Or install Xcode via the App Store.
17      Once installed, run:
18        sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer
19        sudo xcodebuild -runFirstLaunch
20    ✗ CocoaPods not installed.
21        CocoaPods is used to retrieve the iOS and macOS platform side's plugin code that responds to your plugin usage on the Dart side.
22        Without CocoaPods, plugins will not work on iOS or macOS.
23        For more info, see https://flutter.dev/platform-plugins
24      To install see https://guides.cocoapods.org/using/getting-started.html#installation for instructions.
25[✓] Chrome - develop for the web
26[!] Android Studio (not installed)
27[✓] VS Code (version 1.56.2)
28[✓] Connected device (1 available)
29
30! Doctor found issues in 3 categories.

安装java

安装

1└──╼ brew install openjdk@8

刚开始我安装的是 openjdk@11, 但在启动 sdkmanager 时会报

 1└──╼ /usr/local/share/android-sdk/tools/bin/sdkmanager
 2Exception in thread "main" java.lang.NoClassDefFoundError: javax/xml/bind/annotation/XmlSchema
 3    at com.android.repository.api.SchemaModule$SchemaModuleVersion.<init>(SchemaModule.java:156)
 4    at com.android.repository.api.SchemaModule.<init>(SchemaModule.java:75)
 5    at com.android.sdklib.repository.AndroidSdkHandler.<clinit>(AndroidSdkHandler.java:81)
 6    at com.android.sdklib.tool.sdkmanager.SdkManagerCli.main(SdkManagerCli.java:73)
 7    at com.android.sdklib.tool.sdkmanager.SdkManagerCli.main(SdkManagerCli.java:48)
 8Caused by: java.lang.ClassNotFoundException: javax.xml.bind.annotation.XmlSchema
 9    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
10    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
11    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)

查找网上的资料，即使设置了 JAVA_OPTS, 但还是有问题，所以我安装 openjdk@8 而不是 openjdk@11

1└──╼ export JAVA_OPTS='-XX:+IgnoreUnrecognizedVMOptions --add-modules java.se.ee'
2└──╼ /usr/local/share/android-sdk/tools/bin/sdkmanager
3Error occurred during initialization of boot layer
4java.lang.module.FindException: Module java.se.ee not found

配置环境变量

1export JAVA_HOME=/usr/local/opt/openjdk@8
2export PATH=$JAVA_HOME/bin:$PATH

如果未设置 JAVA_HOME 环境变量，后续执行 flutter doctor 可能会报

1The operation couldn’t be completed. Unable to locate a Java Runtime.
2Please visit http://www.java.com for information on installing Java.

安装android sdk

安装sdk
```
1└──╼ brew install android-sdk
```

安装sdk组件首先执行 sdkmanager --list 找到组件最新版本或者选择合适版本

1└──╼ sdkmanager platform-tools
2└──╼ sdkmanager 'platforms;android-29'
3└──╼ sdkmanager 'build-tools;31.0.0-rc4'
4└──╼ sdkmanager --licenses

如果未执行 sdkmanager --licenses 并同意相关协议，在执行 flutter doctor 后可能会提示

1[!] Android toolchain - develop for Android devices (Android SDK version 31.0.0-rc4)
2    ! Some Android licenses not accepted.  To resolve this, run: flutter doctor --android-licenses

配置环境变量

1export ANDROID_SDK_ROOT=/usr/local/share/android-sdk
2export PATH=$ANDROID_SDK_ROOT/tools:$ANDROID_SDK_ROOT/platform-tools:$PATH

初体验

创建一个新的项目

1└──╼ flutter create myapp
2└──╼ cd myapp

注意不要在 flutter sdk 目录里创建项目

1Cannot create a project within the Flutter SDK. Target directory '$HOME/repo/flutter/src/myapp' is within the Flutter SDK at
2'$HOME/repo/flutter'.

配置android模拟器

安装模拟器

1└──╼ sdkmanager emulator
2└──╼ sdkmanager 'system-images;android-29;google_apis;x86_64'

创建新的android模拟器

1└──╼ avdmanager -s create avd -n testAndroid -k "system-images;android-29;google_apis;x86_64"
2└──╼ avdmanager list avd

启动flutter项目

启动模拟器

 1└──╼ flutter emulators
 21 available emulator:
 3
 4testAndroid • testAndroid •  • android
 5
 6To run an emulator, run 'flutter emulators --launch <emulator id>'.
 7To create a new emulator, run 'flutter emulators --create [--name xyz]'.
 8
 9You can find more information on managing emulators at the links below:
10https://developer.android.com/studio/run/managing-avds
11https://developer.android.com/studio/command-line/avdmanager
12└──╼ flutter emulators --launch testAndroid

查看可用驱动

1└──╼ flutter devices
22 connected devices:
3
4Android SDK built for x86 64 (mobile) • emulator-5554 • android-x64    • Android 10 (API 29) (emulator)
5Chrome (web)                          • chrome        • web-javascript • Google Chrome 90.0.4430.212

启动项目
```
1└──╼ flutter run -d emulator-5554
```
至此，我的第一个flutter应用体验完成。很久没学习新的技术，感觉自己都快落伍了，脑子也快生锈了，很早之前就打算自己写一个私人使用的 app，但总抱着一招鲜吃遍天的想法，坚持着熟悉的 vue web app, 而且还道听途说对 flutter 有所怀疑，一直没实际体验过。虽然 vue 足够简单，搭配 cordova 也很方便，但毕竟属于 web app，每种语言或者工具应该都有自己最擅长的领域，比如 vue 之于 web，flutter 至于移动端app，最重要的是，现在技术更新迭代太快，你不学总有人学，学而不思则罔，思而不学则殆，不思不学只会被淘汰

升级Flutter版本

升级步骤

查看当前使用的版本

1└──╼ flutter channel
2
3Flutter channels:
4master
5dev
6beta
7* stable

选择版本(可选)
```
1└──╼ flutter channel stable
```
升级
```
1└──╼ flutter upgrade
```

FAQ

Flutter目录有修改

1[   +8 ms] Your flutter checkout has local changes that would be erased by upgrading. If you want to keep these changes, it is recommended that you stash them via "git stash" or else commit the changes
2to a local
3           branch. If it is okay to remove local changes, then re-run this command with "--force".
4....

进入Flutter目录，使用 git diff

 1──╼ git diff
 2diff --git a/packages/flutter_tools/gradle/flutter.gradle b/packages/flutter_tools/gradle/flutter.gradle
 3index 3db040b967..69db8a4873 100644
 4--- a/packages/flutter_tools/gradle/flutter.gradle
 5+++ b/packages/flutter_tools/gradle/flutter.gradle
 6@@ -24,8 +24,17 @@ import org.gradle.util.VersionNumber
 7
 8 buildscript {
 9     repositories {
10-        google()
11-        jcenter()
12+        // google()
13+        // jcenter()
14+        maven {
15+            url 'https://maven.aliyun.com/repository/jcenter'
16+        }
17+        maven {
18+            url 'http://maven.aliyun.com/nexus/content/groups/public'
19+        }
20+        maven {
21+            url 'https://maven.aliyun.com/repository/google'
22+        }
23     }
24     dependencies {
25         classpath 'com.android.tools.build:gradle:4.1.0'

使用git reset --hard 重置修改，或者使用 flutter upgrade --force 强制更新

FAQ

启动项目报 `Operation timed out`

 1Using hardware rendering with device Android SDK built for x86 64. If you notice graphics artifacts, consider enabling software rendering with
 2"--enable-software-rendering".
 3Launching lib/main.dart on Android SDK built for x86 64 in debug mode...
 4Exception in thread "main" java.net.ConnectException: Operation timed out (Connection timed out)
 5        at java.net.PlainSocketImpl.socketConnect(Native Method)
 6        at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
 7        at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
 8        ......
 9        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:128)
10        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61)
11Running Gradle task 'assembleDebug'...
12Running Gradle task 'assembleDebug'... Done                        76.2s
13Exception: Gradle task assembleDebug failed with exit code 1

这是因为无法下载 gradle 的包和依赖，需要科学上网或者修改为国内源

修改项目目录下的 android/gradle/wrapper/gradle-wrapper.properties 文件

1- distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
2+ distributionUrl=https\://mirrors.cloud.tencent.com/gradle/gradle-6.7-all.zip

修改项目目录下 android/build.gradle

1- google()
2- jcenter()
3+ maven { url 'https://maven.aliyun.com/repository/google' }
4+ maven { url 'https://maven.aliyun.com/repository/jcenter' }
5+ maven { url 'http://maven.aliyun.com/nexus/content/groups/public' }

修改 flutter sdk 目录下 packages/flutter_tools/gradle/flutter.gradle

 1buildscript {
 2     repositories {
 3!        // google()
 4!        // jcenter()
 5!        maven {
 6!            url 'https://maven.aliyun.com/repository/jcenter'
 7!        }
 8!        maven {
 9!            url 'http://maven.aliyun.com/nexus/content/groups/public'
10!        }
11!        maven {
12!            url 'https://maven.aliyun.com/repository/google'
13!        }
14     }
15     dependencies {
16         classpath 'com.android.tools.build:gradle:4.1.0'
17     }
18 }

Unable to locate Android SDK

 1└──╼ flutter doctor
 2Doctor summary (to see all details, run flutter doctor -v):
 3[✓] Flutter (Channel stable, 3.3.4, on macOS 12.5 21G72 darwin-x64, locale zh-Hans-CN)
 4[✗] Android toolchain - develop for Android devices
 5    ✗ Unable to locate Android SDK.
 6      Install Android Studio from: https://developer.android.com/studio/index.html
 7      On first launch it will assist you in installing the Android SDK components.
 8      (or visit https://flutter.dev/docs/get-started/install/macos#android-setup for detailed instructions).
 9      If the Android SDK has been installed to a custom location, please use
10      `flutter config --android-sdk` to update to that location.

解决:

1└──╼ flutter config --android-sdk /usr/local/share/android-sdk
2Setting "android-sdk" value to "/usr/local/share/android-sdk".
3
4You may need to restart any open editors for them to read new settings.

参考文档

python2升级至python3

Mon, 22 Mar 2021 16:35:34 +0000

首先使用工具 2to3 转换
12to3 目录名 -w -n

print

https://stackoverflow.com/questions/55559825/how-to-fix-print-double-parentheses-after-2to3-conversion

问题: 如果在python2项目里使用了python3的写法，比如在 python2 里的 print("test"), 使用 2to3 就会转换成
```
1print(("test"))
```
所以需要找到 print(( 并修复该转换(其实不转也没什么问题)
```
1ag -Gpy 'print(('
```
修复:
```
1- print(("test"))
2+ print("test")
```

string

问题1:

1module 'string' has no attribute 'letters

修复:

1- string.letters
2+ string.ascii_letters

问题2:
```
1'str' object has no attribute 'decode'
```

修复:

1- str.decode(xxx)
2+ str.encode(xxx).decode('unicode_escape')

比值问题

1slice indices must be integers or None or have an __index__ method

问题: python2里 3/2 返回的是整型 1 python3里 3/2 返回的是浮点型 1.5
修复:
```
1print(3//2)
2# 或者
3print(int(3/2))
```

编码问题

sys.setdefaultencoding('utf-8')

python2里的 sys.setdefaultencoding('utf-8') 需要删除

encode、decode

问题:

1LookupError: 'base64' is not a text encoding; use codecs.encode() to handle arbitrary codecs

语法:

python2

1Python 2.7.16 (default, Dec 21 2020, 23:00:36)
2[GCC Apple LLVM 12.0.0 (clang-1200.0.30.4) [+internal-os, ptrauth-isa=sign+stri on darwin
3Type "help", "copyright", "credits" or "license" for more information.
4>>> a = "a"
5>>> a.encode("base64")
6'YQ==\n'
7>>> b = a.encode("base64")
8>>> b.decode("base64")
9'a'

python3

1Python 3.7.4 (default, Sep  7 2020, 15:30:33)
2[Clang 11.0.3 (clang-1103.0.32.29)] on darwin
3Type "help", "copyright", "credits" or "license" for more information.
4>>> a = "a"
5>>> a.encode("base64")
6Traceback (most recent call last):
7  File "<stdin>", line 1, in <module>
8LookupError: 'base64' is not a text encoding; use codecs.encode() to handle arbitrary codecs

修复:

1import base64
2
3def b64encode(s):
4    if isinstance(s, bytes):
5        return base64.b64encode(s)
6    return base64.b64encode(s.encode('utf-8')).decode('utf-8')
7
8def b64decode(s):
9    return base64.b64decode(s).decode('utf-8')

1- x.encode('base64')
2- x.decode('base64')
3+ b64encode(x)
4+ b64decode(x)

编码转换

utf-8转换为gbk

python2

1'hello世界'.decode('utf-8').encode('gbk')

python3

1''.join([chr(i) for i in 'hello世界'.encode('gbk')])
2# 或者
3'hello世界'.encode('gbk').decode('unicode_escape')

cmp

python3里cmp内置函数不再存在，需要自定义函数

1def cmp(a, b):
2    return (a > b) - (a < b)

sorted

python2里sorted有一个cmp参数，python3里统一为key参数

python2

1sorted(keys, lambda x, y: cmp(len(x), len(y)), reverse=True)

python3

1from functools import cmp_to_key
2
3sorted(keys, key=cmp_to_key(lambda x, y: cmp(len(x), len(y))), reverse=True)

注意: must use keyword argument for key function

Exception

python3里没有 .message, 所以需要修改 e.message 为 str(e)

python3无法使用 as 直接对变量赋值

 1def main():
 2    err = None
 3    try:
 4        raise ValueError("sss")
 5    -    except Exception as err:
 6    -       pass
 7    +    except Exception as e:
 8    +       err = e
 9    return err
10
11print(main())

1UnboundLocalError: local variable 'err' referenced before assignment

SSL

问题:

1File "/usr/local/lib/python3.6/dist-packages/OpenSSL/SSL.py", line 1591, in set_tlsext_host_name
2raise TypeError("name must be a byte string")

解决

1- s.set_tlsext_host_name(hostname)
2+ s.set_tlsext_host_name(hostname.encode('utf-8'))

file.read

1with open("test.txt", "rb") as f:
2    for i in f.read(10):
3        print(i, type(i))

python2

1('\x7f', <type 'str'>)
2('E', <type 'str'>)
3('\x00', <type 'str'>)

python3

1127 <class 'int'>
269 <class 'int'>
30 <class 'int'>

两者之间的转换
```
1ord('\x7f') == 127
2chr(127) == '\x7f'
```

redis

python3里默认取出的值是 bytes 类型, 需要客户端添加 decode_responses=True 参数, 取出的值才是 str 类型

requests

自定义编码请求

https://github.com/psf/requests/issues/4133

post json

python2

1data = {'test': 'hello世界'.decode('utf-8').encode('gbk')}
2headers = {'Content-Type': 'application/json;charset=gbk'}
3data=json.dumps(data,ensure_ascii=False)
4rsp = requests.post("/dynamic/test", data=data,headers=headers)

python3

1data = {'test': 'hello世界'}
2headers = {'Content-Type': 'application/json;charset=gbk'}
3data=json.dumps(data, ensure_ascii=False)
4resp = requests.post("/dynamic/test", data=data.encode('gbk'), headers=headers)

post form

python2

1data = {'test': 'hello世界'.decode('utf-8').encode('gbk')}
2headers = {'Content-Type': 'application/x-www-form-urlencoded;charset=gbk'}
3resp = requests.post("/dynamic/test", data=data,headers=headers)

python3

1data = {'test': 'hello世界'.encode('gbk')}
2headers = {'Content-Type': 'application/x-www-form-urlencoded;charset=gbk'}
3resp = requests.post("/dynamic/test", data=data,headers=headers)

响应编码

1resp = requests.get("...")
2print(type(resp.content))
3print(type(resp.text))

python2 resp.content 是 str 类型, resp.text 是 unicode 类型
python3 resp.content 是 bytes 类型, resp.text 是 str 类型

请求headers顺序

根源主要在 requests.structures 的 CaseInsensitiveDict 类

 1from requests.structures import CaseInsensitiveDict
 2from collections import OrderedDict
 3
 4headers = {
 5    'Accept-Language': 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4',
 6    'Accept-Encoding': 'gzip, deflate, sdch',
 7    'cache': 0,
 8    'host': 'Host1.com',
 9    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8',
10    'User-Agent': 'curl/7.29.0',
11    'Host': 'Host2.com'
12}
13print(headers)
14
15r = CaseInsensitiveDict()
16r.update(headers)
17print(r)

不同的python版本结果会输出

python2

1OrderedDict([('Accept-Language', 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4'), ('Accept-Encoding', 'gzip, deflate, sdch'), ('cache', 0), ('Host', 'Host2.com'), ('Accept', 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8'), ('User-Agent', 'curl/7.29.0'), ('host', 'Host1.com')])
2CaseInsensitiveDict({'Accept-Language': 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4', 'Accept-Encoding': 'gzip, deflate, sdch', 'cache': 0, 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'User-Agent': 'curl/7.29.0', 'host': 'Host1.com'})

python3

1OrderedDict([('Accept-Language', 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4'), ('Accept-Encoding', 'gzip, deflate, sdch'), ('cache', 0), ('host', 'Host1.com'), ('Accept', 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8'), ('User-Agent', 'curl/7.29.0'), ('Host', 'Host2.com')])
2{'Accept-Language': 'en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4', 'Accept-Encoding': 'gzip, deflate, sdch', 'cache': 0, 'Host': 'Host2.com', 'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8', 'User-Agent': 'curl/7.29.0'}

所以如果要兼容两个版本，需要显示的传入

1headers = OrderedDict(sorted(headers.items(), key=lambda x: x[0]))

django

1- for k, v in request.GET.iterlists():
2+ for k, v in request.GET.lists():

并且k和v的类型在python3里默认为 str ，不需要使用 k.encode("utf-8") 进行转换

pyenv笔记

Thu, 18 Mar 2021 15:29:39 +0000

常见问题

pyenv install 3.6.7 失败

环境: macOs big Sur 11.2.2

pyenv: 1.2.23

解决方式

1┌─[jianglin]─[~/repo/golang/src/alarm](master)
2└──╼ CFLAGS=-Wno-implicit-function-declaration  pyenv install --patch 3.6.7 < <(curl -sSL https://github.com/python/cpython/commit/8ea6353.patch\?full_index\=1)
3python-build: use openssl@1.1 from homebrew
4python-build: use readline from homebrew
5Installing Python-3.6.7...
6curl: (7) Failed to connect to github.com port 443: Operation timed out
7python-build: use readline from homebrew
8python-build: use zlib from xcode sdk
9Installed Python-3.6.7 to /Users/jianglin/repo/python/pyenv/versions/3.6.7

参考文档

golang笔记之struct转map性能比较

Mon, 21 Sep 2020 11:38:24 +0000

测试代码

 1package main
 2
 3import (
 4    "encoding/json"
 5    "reflect"
 6    "testing"
 7)
 8
 9type A struct {
10    A string   `json:"a"`
11    B string   `json:"b"`
12    C int      `json:"c"`
13    D int      `json:"d"`
14    E []string `json:"e"`
15    F []int    `json:"f"`
16}
17
18var a = &A{
19    "string",
20    "test",
21    15,
22    1024,
23    []string{"vvv", "ssss", "44444"},
24    []int{100, 4012},
25}
26
27func Struct2Map(value interface{}) map[string]interface{} {
28    v := reflect.ValueOf(value)
29    for v.Kind() == reflect.Ptr {
30        v = v.Elem()
31    }
32    t := v.Type()
33
34    res := make(map[string]interface{})
35    for i := 0; i < t.NumField(); i++ {
36        if tag := t.Field(i).Tag.Get("json"); tag != "" && tag != "-" {
37            res[tag] = v.Field(i).Interface()
38        }
39    }
40    return res
41}
42
43func Struct2MapByJson(value interface{}) map[string]interface{} {
44    bs, err := json.Marshal(value)
45    if err != nil {
46
47    }
48
49    res := make(map[string]interface{})
50    if err := json.Unmarshal(bs, &res); err != nil {
51
52    }
53    return res
54}
55
56func Benchmark_Json2Map(b *testing.B) {
57    for i := 0; i < b.N; i++ {
58        Struct2MapByJson(a)
59    }
60}
61
62func Benchmark_Reflect2Map(b *testing.B) {
63    for i := 0; i < b.N; i++ {
64        Struct2Map(a)
65    }
66}

测试结果

1└──╼ go test -test.bench=".*" .
2goos: darwin
3goarch: amd64
4pkg: maple-test1
5Benchmark_Json2Map-8          241076          4672 ns/op
6Benchmark_Reflect2Map-8      1000000          1005 ns/op
7PASS
8ok      maple-test1	2.971s

rust笔记

Tue, 08 Sep 2020 17:10:53 +0000

安装

1└──╼ brew install rustup
2└──╼ rustup-init
3......
41) Proceed with installation (default)
52) Customize installation
63) Cancel installation
7>1

配置 rust 目录

1└──╼ mkdir $HOME/repo/rust
2└──╼ mv $HOME/.rustup $HOME/repo/rust/rustup
3└──╼ mv $HOME/.cargo $HOME/repo/rust/cargo

写入 .bashrc 文件

1export RUSTUP_HOME=$HOME/repo/rust/rustup
2export CARGO_HOME=$HOME/repo/rust/cargo
3export PATH=$PATH:$HOME/repo/rust/cargo/bin

验证

1└──╼ source .bashrc
2└──╼ cargo --version
3cargo 1.46.0 (149022b1d 2020-07-17)

更新

最近在测试时发现无法安装 tauri-app, 需要更新 cargo

1Caused by:
2  failed to parse the `edition` key
3
4Caused by:
5  this version of Cargo is older than the `2021` edition, and only supports `2015` and `2018` editions.

解决方式

1└──╼ rustc --version
2rustc 1.46.0 (04488afe3 2020-08-24)
3└──╼ rustup update stable
4...
5└──╼ rustc --version
6rustc 1.64.0 (a55dd71d5 2022-09-19)

交叉编译

https://www.qttc.net/529-rust-cross-compile-mac-to-linux.html

https://moevis.github.io/cheatsheet/2018/08/18/%E8%B6%85%E6%96%B9%E4%BE%BF%E7%9A%84-Rust-%E4%BA%A4%E5%8F%89%E7%BC%96%E8%AF%91.html

1brew install FiloSottile/musl-cross/musl-cross
2rustup target add x86_64-unknown-linux-musl

添加配置 $CARGO_HOME/config.toml

1[target.x86_64-unknown-linux-musl]
2linker = "x86_64-linux-musl-gcc"

1cargo build --target=x86_64-unknown-linux-musl

红枫吟 - Develop

关于Android模拟器无法连接网络

Flutter实现本地化多语言

内置组件本地化

自定义本地化

自定义本地化(非代码自动生成)

本地化多语言的使用

优化多语言选择

参考文档

使用Go重写MetingJS的API

功能

使用

手动部署

Docker部署

配置说明

命令行参数

网页端设置

演示

基于Quasar实现一个树状选择器TreeSelect

源数据结构

组件模版

组件选项

最终实现

基于Quasar实现一个树状表格TableTree

前言

实现一(废弃)

实现二

最终实现

flutter笔记之初体验

安装

安装flutter

安装java

安装android sdk

初体验

创建一个新的项目

配置android模拟器

启动flutter项目

升级Flutter版本

升级步骤

FAQ

FAQ

启动项目报 Operation timed out

Unable to locate Android SDK

参考文档

python2升级至python3

print

string

比值问题

编码问题

sys.setdefaultencoding('utf-8')

encode、decode

编码转换

cmp

sorted

Exception

SSL

file.read

redis

requests

自定义编码请求

post json

post form

响应编码

请求headers顺序

django

pyenv笔记

常见问题

pyenv install 3.6.7 失败

相关日志

解决方式

参考文档

golang笔记之struct转map性能比较

测试代码

测试结果

rust笔记

安装

更新

交叉编译

启动项目报 `Operation timed out`