[Angular 2] Async Http

[Angular] Bind async requests in your Angular template with the async pipe and the "as" keyword

Angular allows us to conveniently use the async pipe to automatically register to RxJS observables and render the result into the template once the request succeeds. This has some drawbacks, especially if we want to bind the same data in multiple par…

Async Pipe: The Asynce pipe receive a Promise or Observable as input and subscribes to the input, evetually emitting the value(s) changes arrive. In the demo, the logic is fom the list component, we ask service to get Heros by calling Start War API,…

[Angular] New async 'as' syntax and ngIf.. else

From Anuglar v4 above, we are able to using 'as' with async pipe. This allow as using 'new variable' instead of subscribe to observable. We also able to use 'else' with '*ngIf', else taks a 'template' which will be displayed when the if expression is…

angular学习笔记(二十九)-$q服务

angular中的$q是用来处理异步的(主要当然是http交互啦~). $q采用的是promise式的异步编程.什么是promise异步编程呢? 异步编程最重要的核心就是回调,因为有回调函数,所以才构成了异步编程,而回调有三个关键部分: 一是什么时候执行回调,二是执行什么回调,三是回调执行的时候传入什么参数. 就以最常见的jquery Ajax举例,发送一个请求后: 什么时候执行回调: 请求成功(或者失败)的时候执行什么回调: 根据请求成功或者失败,执行相应的回调函数回调执行的时候传入的什么…

Working with Validators and Messages in AngularJS

原文:http://odetocode.com/blogs/scott/archive/2014/10/16/working-with-validators-and-messages-in-angularjs.aspx --------------------------------------------------------------------------------------------------------------- In a previous post we looked…

[Angular 2] Handle Reactive Async opreations in Service

When you use ngrx/store and you want to fire a service request. When it sucessfully return the response, you need to dispatch action to tell the store update. So one pattern can be considered to follow is: import {Http, Headers} from '@angular/http';…

[Angular 2] Rendering an Observable with the Async Pipe

Angular 2 templates use a special Async pipe to be able to render out Observables. This lesson covers the syntax used to create an Observable in Angular 2 and then to render it out in the template. import {Component} from 'angular2/core'; import {boo…

[Angular 2] Controlling Rx Subscriptions with Async Pipe and BehaviorSubjects

Each time you use the Async Pipe, you create a new subscription to the stream in the template. This can cause undesired behavior especially when network requests are involved. This lesson shows how to use a BehaviorSubject to observe the http stream…

[Angular 2] Passing Observables into Components with Async Pipe

The components inside of your container components can easily accept Observables. You simply define your custom @Input then use the Async pipe when you pass the Observable in. This lesson walks you through the process of passing an Observable into a…

[Angular 2] Rendering an Observable Date with the Async and Date Pipes

Instead of simply pushing numbers on a timer into the template, now we'll move on to pushing actual Dates. We'll still use the Async pipe, but we'll also add on the Date pipe with some formatting to display the Date just the way we want it. import {C…

[Angular] Show a loading indicator in Angular using *ngIf/else, the as keyword and the async pipe

The network may be unreliable and loading data may take time. Thus it is important to give the user some feedback about what's going on as fast as possible. In this lesson we learn how to leverage the else block of the *ngIf directive to show a simpl…

[Angular] Test Container component with async provider

The main idea for testing contianer component is to make sure it setup everythings correctlly. Call the onInit() lifecycle first, then the variables have the right value. Methods will be called with the right params. Container component: import { Com…

TypeScript: Angular 2 的秘密武器（译）

本文整理自Dan Wahlin在ng-conf上的talk.原视频地址: https://www.youtube.com/watch?v=e3djIqAGqZo 开场白开场白主要分为三部分: 感谢了ng-conf的组织者. 阐述了TypeScript是JavaScript的超集,并不是另外一种语言. 引用了他的两个朋友最喜欢的TypeScript特性. 由于开场白内容不太重要,所以不再详述.下面开始讲解Dan Wahlin最喜欢的TypeScript的特性. 类型支持(Type Support…

深入理解jQuery、Angular、node中的Promise

最初遇到Promise是在jQuery中,在jQuery1.5版本中引入了Deferred Object,这个异步队列模块用于实现异步任务和回调函数的解耦.为ajax模块.队列模块.ready事件提供基础功能.在用jQuery操作DOM的时候对Promise的使用欲不够强烈,最近学习node和Angular,需要用js写业务逻辑和数据操作代码的时候这种场景需求就出来了.一般来说事件适合在交互场景中运用,因为用户的行为本来就是分散的,而promise这样的流程控制适合在后台逻辑中处理业务. //j…

angular源码分析：angular中$rootscope的实现——scope的一生

在angular中,$scope是一个关键的服务,可以被注入到controller中,注入其他服务却只能是$rootscope.scope是一个概念,是一个类,而$rootscope和被注入到controller中的一个具体的$scope都是一个个具体的对象.$rootscope之所以被称为"root"的原因就是他是所有scope的祖先,$rootscope是在angular启动流程中建立的(上上期讲过),而被注入到controller中的$scope则是在视图创建的时候通过父辈的$s…

angular实现了一个简单demo，angular-weibo-favorites

前面必须说一段帮客户做了一个过渡期的项目,唯一的要求就是速度,我只是会点儿基础的php,于是就用tp帮客户做了这个项目.最近和客户架构沟通,后期想把项目重新做一下,就用现在最流行的技术,暂时想的使用angular做前端框架,为了后期还能继续兼职参与.于是就学习了一下. 前端的东西好多,更新的速度好快,百度搜了一下angular,出来的技术博文都是好多,又不清楚使用的angular的版本,不过看日期就知道自己学习晚了.不过不得不提到大漠穷秋老师的教程不错,正在学习的同学的可以去看看他的教程. d…

activiti自定义流程之整合（二）：使用angular js整合ueditor创建表单

注:整体环境搭建:activiti自定义流程之整合(一):整体环境配置基础环境搭建完毕,接下来就该正式着手代码编写了,在说代码之前,我觉得有必要先说明一下activit自定义流程的操作. 抛开自定义的表单不谈,通过之前的了解,我们知道一个新的流程开始,是在启动流程实例(processIntence)的时候,而流程实例依赖于流程定义(processDefinition),流程定义又依赖于流程模型(model). 我们用到的自定义表单需要在创建模型,画模型图的时候就指定表单的名称formKey,需…

[Angular2 Router] Load Data Based on Angular 2 Route Params

You can load resource based on the url using the a combination of ActivatedRouteand Angular 2’s Http service. Since the params and Http are both streams, you can use RxJS to get the data off the param then switchMap over to an Http request using that…

[AngularJS] Lazy loading Angular modules with ocLazyLoad

With the ocLazyLoad you can load AngularJS modules on demand. This is very handy for runtime loading of Angular modules in large applications. Simple example: angular.module("demo", ["oc.lazyLoad"]) .controller("AppCtrl", fun…

Redux你的Angular 2应用--ngRx使用体验

Angular2和Rx的相关知识可以看我的Angular 2.0 从0到1系列第一节:Angular 2.0 从0到1 (一)第二节:Angular 2.0 从0到1 (二)第三节:Angular 2.0 从0到1 (三)第四节:Angular 2.0 从0到1 (四)第五节:Angular 2.0 从0到1 (五)第六节:Angular 2.0 从0到1 (六)第七节:Angular 2.0 从0到1 (七)第八节:Angular 2.0 从0到1 (八)番外:Angular 2.0 从0到1…

Angular 2.0 从0到1：Rx--隐藏在Angular 2.x中利剑

第一节:Angular 2.0 从0到1 (一)第二节:Angular 2.0 从0到1 (二)第三节:Angular 2.0 从0到1 (三)第四节:Angular 2.0 从0到1 (四)第五节:Angular 2.0 从0到1 (五)第六节:Angular 2.0 从0到1 (六)第七节:Angular 2.0 从0到1 (七)第八节:Angular 2.0 从0到1 (八)番外:Angular 2.0 从0到1 Rx-隐藏在Angular 2.x中利剑番外:Angular 2.0 从0到…

angular中的promise

angular中的promise用法标签(空格分隔): angular 前言 Promise其实是一个规范,用类似then().then()这样的链式调用形式来处理因为异步带来意大利面条式的代码(多层函数嵌套). 多层函数嵌套的原因是,因为js的异步特性,导致我们后面函数需要用到这个异步函数获取的数据或者结果时,必须要等异步函数处理完成.所以必须写在这个异步函数结尾. Angular中的promise:$q Angular把promise封装成了一个服务$q方便我们到处使用它. 当我们用con…

[Angular 2] ngrx/store

@ngrx/store builds on the concepts made popular by Redux and supercharges it with the backing of RxJS. The result is a tool and philosophy that will transform the way you approach state management in your Angular 2 applications. This lesson takes an…

[Angular 2] Passing Template Input Values to Reducers

Angular 2 allows you to pass values from inputs simply by referencing them in the template and passing them into your Subject.next() call. This lesson shows you how to make a number input and pass the value so you can configure how much you want the…

[Angular 2] Using ngrx/store and Reducers for Angular 2 Application State

ngrx/store is a library that simplifies common RxJS patterns for managing state and gives you an easy api to use it within your Angular 2 application. This lesson shows how to convert a common startWith and scan stream into an ngrx Store and reducer.…

[Angular 2] Handling Click Events with Subjects

While Angular 2 usually uses event handlers to manage events and RxJS typically uses Observable.fromEvent, a good practice when using Angular 2 and RxJS combined is to use Subjects and push the value through each event so that you can use it as part…

Angular源代码学习笔记-原创

时间:2014年12月15日 14:15:10 /** * @license AngularJS v1.3.0-beta.15 * (c) 2010-2014 Google, Inc. http://angularjs.org * License: MIT */ (function(window, document, undefined) {'use strict'; /** * @description * * This object provides a utility for produc…