小编Nau*_*wir的帖子

我对本机反应还很陌生。我正在尝试为我的应用设置一些全局标题样式，但是它不起作用

route.js

import React, { Component } from 'react';
import { View } from 'react-native';
import { createStackNavigator, createAppContainer } from "react-navigation";
import SplashScreen from '../screens/SplashScreen';
import CalendarScreeen from '../screens/CalendarScreen';

const NavStack = createStackNavigator(
    {
        Splash: {
            screen: SplashScreen,
            navigationOptions: {
                header: null
            },
        },
        Calendar: {
            screen: CalendarScreeen,
            navigationOptions: {
                title: 'Calendar',
            },
        },
    },
    {
        initialRouteName: 'Calendar',
        navigationOptions: {
            headerStyle: {
                backgroundColor: '#28F1A6',
                elevation: 0,
                shadowOpacity: 0
            },
            headerTintColor: '#333333',
            headerTitleStyle: {
                fontWeight: 'bold',
                color: '#ffffff'
            }
        } …

因此，我将reminder componenttextInput 从 react-native 导入，DatePicker 从本机库导入，还有一个按钮将在单击事件时保存表单。

现在，当我点击日期选择器，它提供了一个错误说：value for date cannot be cast from string to double。我还附上了错误的屏幕截图。

不知道我哪里出错了。

这是组件的代码。

class Reminder extends Component {

    constructor(props) {
        super(props);
        let formatDate = new Date();
        this.state = {
            chosenDate: formatDate.toISOString().split('T')[0],
            text: '',
        };
        this.handleChangeInput = this.handleChangeInput.bind(this);
        this.saveData = this.saveData.bind(this);
    }


    render() { 
        const {chosenDate} = this.state;
        return ( 
            <View>
                <Form style={styles.formContainer}>
                    <View style={styles.formView}>

                        < TextInput
                            placeholder = "Set your reminder"
                            onChangeText={this.handleChangeInput}
                            value={this.state.text}
                        />

                        <DatePicker
                            defaultDate={chosenDate}
                            mode = "date"
                            animationType={"fade"}
                            androidMode={"default"} …

我无法在侧边栏中显示可用标签列表,在ghost博客中.

我是tag.hbs文件,代码如下.

    <header class="main-header tag-head {{#if tag.image}}" style="background-image: url({{tag.image}}){{else}}{{#if @blog.cover}}" style="background-image: url({{@blog.cover}}){{else}}no-cover{{/if}}{{/if}}">
    <nav class="main-nav overlay clearfix">
        <a class="back-button icon-arrow-left" href="{{@blog.url}}">Home</a>
    </nav>
    <div class="vertical">
        <div class="main-header-content inner">
            <h1 class="page-title">{{tag.name}}</h1>
            <h2 class="page-description">
                {{#if tag.description}}
                    {{tag.description}}
                {{else}}
                    A {{pagination.total}}-post collection
                {{/if}}
            </h2>
        </div>
    </div>
</header>

{{! The main content area on the homepage }}
<main class="content" role="main">
    <div class="container">
        <div class="row-fluid">
            <div class="col-md-12">
                {{! The tag below includes the post loop - partials/loop.hbs }}
                {{> "loop"}}
            </div>
        </div>
    </div>

</main>
{{> …

let users = [
    { id: 11, name: 'Adam', age: 23, group: 'editor' },
    { id: 47, name: 'John', age: 28, group: 'admin' },
    { id: 85, name: 'William', age: 34, group: 'editor' },
    { id: 97, name: 'Oliver', age: 28, group: 'admin' }
  ];

var getFilteredUsers = (array, key, value) => array.filter(x => x[key] === value);
var FilteredUsers = getFilteredUsers(users, "age", 28);
console.log(FilteredUsers);

我正在尝试创建一个动态过滤器，基于key:value传入的结果getgetFilteredUsers()将给出相应的输出。

现在，getgetFilteredUsers()只有计算equals to。但是我想使用相同的功能比较所有三个比较，即等于，小于和大于。

这是我的firebase.js

import { initializeApp } from "firebase/app";

import { getFirestore } from "firebase/firestore";

import { getAuth } from "firebase/auth";
import { getAnalytics, logEvent, isSupported } from "firebase/analytics";

//  Update the config
var firebaseConfig = {
  // ...Update config
 
};

// Initialize Firebase

const app = initializeApp(firebaseConfig);
const firestore = getFirestore(app);
const auth = getAuth();
const analytics = getAnalytics(app);

// Uncomment the following if you want to use emulator
// if (process.env.NODE_ENV === "development") {
//   firestore.useEmulator("localhost", 8080);
//   auth.useEmulator("http://localhost:9099"); …

我试图模仿array.map()使用forEach().

var map = function () {
  var empMap = [];
  numbers.forEach(function (number) {
    empMap.push(number);
    console.log('empMap', empMap);
  });
  return(empMap);
}

var numbers = [1, 2, 3];
//implement this line

var doubles = map(numbers, function (number) {
  return number * 2;
});
console.log(doubles); // [2, 4, 6]

所以,我有这个numbers数组的值,我有自己map function的迭代数组,然后我推动空数组中的值empMap

之后,我调用这个map函数并将每个值乘以2并将其打印出来.

我应该得到双倍的输出为[2,4,6]而不是[1,2,3].不知道我哪里错了.

这是同样的[codepen] 1.