Browse Lessons by Technology
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Let’s look at the GitHub commits and list of contributors now that our pull request has been merged. And we’ll wrap this series up with a few tips. Feel free to practice on stack-overflow-copy-paste, and see the Pull Request demonstrated in this lesson here.
Often, project maintainers prefer that a single pull request be represented by a single commit. It makes the git history cleaner and easier to understand. So before your pull request is merged you’ll want to do an interactive git rebase to squash all of your commits and fix your commit message.
Sometimes your Pull Request can fall behind master in a repository and occasionally that will result in merge conflicts which you have to manage yourself. In this lesson we’ll learn how to use
git rebase to update our pull request branch to the latest version of master and resolve merge conflicts with git.
Once you’ve made your code updates locally, all you need to do is commit those changes and push that commit to your Pull Request branch. In this lesson we’ll also talk about how to skip git hooks that may be included in the project when you just need help.
It’s not often that you’ll get a Pull Request on GitHub just right the first time you try. You generally will iterate with the project maintainer on your solution before your PR gets merged. In this lesson, we’ll explore some of the tools that projects use to manage contributions to open source projects on GitHub.
Often when making a change, you want to verify your approach with the maintainer or ask them for help. In this lesson we’ll make a change and commit that WIP change. Then we’ll create a pull request requesting help from the project maintainer.
Before you start making your change, you often need to set up your environment for the changes. This is where the repositories contributing instructions come in really handy. In this lesson we’ll get our environment setup and ready for changes.
You cannot push code to repositories that you don’t own or have sufficient permission to. So instead, you make your own copy of the repository by “forking” it. You are then free to make any changes you wish to your repository.
When you find a bug in an open source project, you know exactly the change you want to make. Other times you just want to find a way to contribute. Either way, you’ll need to know how to the project maintainers want to run the project and work with them to come up with an implementation for the fix/feature. And if you don't even know what project to start contributing to, check out this blogpost for inspiration on how to identify a good project to contribute to.
Anytime you push code to GitHub, you must be authenticated so GitHub knows you are authorized to make changes. In this lesson we’ll learn how to authenticate with GitHub using SSH so we don’t have to enter our username and password each time we push code to GitHub.
Let’s install the Git Source Control Management software so we can interact with repositories hosted on GitHub.
The basic unit of GitHub is a repository. This is where you code is stored and GitHub allows you to interact with others and with the code in great ways. In this lesson we talk about Watching, Staring, and Forking a repository. We also cover GitHub issues and pull requests and various other stats about a GitHub repository.
GitHub adds a lot of great features on top of git repository hosting. We’ll take a look at some of these features including:
In this lesson we’ll talk about what GitHub is and how to sign up for a GitHub account so you can contribute to an open source project on GitHub.
Sometimes, the helper methods that RxJS ships with such as
fromPromise etc don't always provide the exact values you want & you end up having to do extra work to force them into the shape you require. For more fine-grained control you can use
Observable.create which allows you to project only the values which matter to you.
The CSS :not() selector allows us to exclude a subset of elements matched by our selector. In this example we refactor two selectors down to one using the CSS :not() selector.
In this lesson, we learn how to build modals in Ionic. We use the
ion-modal-view directive to wrap our “create” and “edit” forms with modal goodness, as well as use the
ion-header-bar directive to put a nice bar at the top of our forms. Finally, we use the
$ionicModal service to give life to our modals by integrating them with our controllers.
In this lesson, we are going to dig into Ionic lists and make use of some awesome list features that Ionic gives us for free. We are going to learn how to use the following Ionic directives:
ionItem, this element allows a developer to show/hide a delete button within an
ionItem, this element allows a developer to reorder an
ionItemwithin a list easily.
In this lesson, we are going to turn two forms into Angular directives in preparation for turning them into Ionic modals. This isn’t a complicated step, but it puts us in a better place for creating the modals.
In this lesson, we learn how to build a sidebar layout using only Ionic directives. Ionic provides some powerful functionality with very few semantics. Here are all the directives we will learn about:
- ion-side-menus - A container element for side menu(s) and the main visible content.
- ion-side-menu-content - A container for the main visible content, sibling to one or more
- ion-side-menu - A container for a side menu, sibling to an
- ion-nav-view - Used to render templates in your application. Each template
is part of a state. States are usually mapped to a url, and are defined programatically
using angular-ui-router (see their docs for reference).
- ion-view - A container for view content and any navigational and header bar information. Used as a child of
- ion-nav-bar - If we have an
ionNavView directive, we can also create an
ionNavBar, which will create a topbar that updates as the application state changes.
- ion-nav-buttons - Use nav buttons to set the buttons on your
from within an
- ion-content- Provides an easy to use content area that can be configured
to use Ionic’s custom Scroll View, or the built in overflow scrolling of the browser.
- ion-list - The List is a widely used interface element in almost any mobile app, and can include
content ranging from basic text all the way to buttons, toggles, icons, and thumbnails.
- ion-item - Used to create items inside of an
In this lesson, we are going to learn how to interact with native components through Cordova plugins. We will walk through how to add a Cordova plugin to our application and use it to interact with our native device. In this case, we are going to install a plugin that will allow us to open URLs in a mobile browser from within our Ionic app.
In this lesson, we are going to include the necessary assets for the functionality and styles of the Ionic directives we will include in our app.
In this lesson, we are going to build an Ionic app for the iOS platform, and then emulate iOS on our computer. We are going to cover some important command-line options when emulating an Ionic application. We will then see how these options play a critical role in debugging our applications.
In this lesson, we are going to demonstrate how easy it is to copy existing Angular code into an Ionic app. It is literally as simple as removing unnecessary code from the Ionic app and pasting in the guts of our Angular application. Along the way, we will update some dependencies and discover a gotcha for including assets from a CDN.
In this lesson, we learn how to install Ionic and Cordova. We then build an app from scratch using the Ionic CLI and a blank starter template.
window.location but they differ in how they interact with Session History (and hence, the browser's back button). In this lesson, you'll learn how they're different and how to use each of them.
There are certain situations in which you’ll want access to the latest values from multiple Observables whenever any one of them produces a value. This is exactly what
combineLatest was designed for, and in this lesson we’ll use it to build up an image url that requires values from 3 different inputs - triggered every time any one of them change.
We are going to take a high-level look at what an Elm application looks like? We show how to structure apps, as well as, Elm’s elegant syntax by building a small app.
This lesson shows what can be learned next as a continuation of this course, and gives a recap on the core concepts: main for pure logic, drivers for side effects, run() to connect main and drivers, sources for read effects, sinks for write effects, and nesting Cycle.js apps to work as components.
Our app is not yet a BMI calculator, because it only has two sliders, but doesn't show the calculated BMI number. In this lesson we will learn how to export any stream from a child component and use it in the parent component, in order to display the BMI calculation on the DOM.
We added classNames to pre-processing and post-processing steps when calling the LabeledSlider, in order to instances independent of each other. It would be better if we could hide these steps away. This lesson introduces the isolate() helper function to achieve that.
Once we have a labeled slider component inside the main function, we should be able to create another labeled slider. This lesson teaches how to accomplish that, and make sure those two instances work independently of each other.
We have made a Cycle.js app for generic labeled slider which can be configured through props, but how can we reuse it in other Cycle.js apps? This lesson shows how we can embed any Cycle program inside a larger Cycle program in a very simple manner.
We are starting to get a better architecture for these UI apps. But we still have a problem of repeating code for the sliders, since they share so much in common in looks and functionality. This lessons shows how we can create a generic labeled slider as a main() function receiving properties as sources.
We built the BMI calculator all inside one function: main(). As apps scale, we don't want main() to grow. We need an organized pattern where each function focuses on doing one thing. This lesson shows how we can easily refactor the main() function into three parts: Intent, Model, and View.
So far we have been writing very small apps in Cycle.js. Let's start growing the size of the apps we build. This time, we will see how to build a simple Body-Mass Index Calculator.
Let's see next how to use the HTTP driver to generate requests and capture responses. We will build a small app to fetch a single piece of data from a REST server and display that on the DOM.
This lesson shows how we can create a more interactive app: a counter display with buttons to increment and decrement it. This reveals how we can use the RxJS scan() operator to remember past values and keep state.
Now you should have a good idea what Cycle.run does, and what the DOM Driver is. In this lesson, we will not build a toy version of Cycle.js anymore. Instead, we will learn how to use Cycle.js to solve problems. We will start by making a simple Hello world application.
This lessons shows how we are able to easily swap our toy DOM Driver with the actual Cycle.js DOM Driver, a more solid, more flexible, more efficient implementation.
Usually we use template languages like Handlebars, JSX, and Jade to create. One simple way we can create our own template language is to write a function that returns these objects for us. This lessons shows how we can use these functions as a DSL to create our DOM description objects.
What if wanted to change the behavior of our app reset the timer every time the mouse hovers over it? Currently we only support clicks, and they are hard coded in the DOM Driver. This lesson will introduce DOMSource.selectEvents(), a way of making the DOM Source rich and allowing the main() function to determine which read effects it needs.
Our previous toy DOM Driver is still primitive. We are only able to sends strings as the textContent of the container element. We cannot yet create headers and inputs and all sorts of fancy DOM elements. In this lesson we will see how to send objects that describe what elements should exist, instead of strings as the DOM sink.
Our application was able to produce write effects, through sinks, and was able to receive read effects, through the DOM sources. However, the main function only gets the DOMSource as input. This lessons shows how we can generalize main to receive an object of sources, containing all kinds of read effects that we can use.
So far we only had effects that write something to the external world, we are not yet reading anything from the external world into our app. This lesson shows how we can change the DOM Driver to return a "DOM Source" representing read effects, such as click events. We will leverage that to create an interactive application.
The last part of the code we wrote is neither logic nor effects. It is code which ties together logic (main) with effects. We can encapsulate that in a run() function. This lesson shows how we can structure these pieces together, and generalize effect handling with "drivers".
How can we show one string on the DOM, and a completely different string on Console log? This lesson shows how we can make our main function return multiple Observables, each one targeted at a different type of effect.
We need to give structure to our application with logic and effects. This lessons shows how we can organize our code into two parts: main() function for logic, and effects functions for effects.
This lesson is the first in an introduction to Cycle.js. We will see how to build from scratch a toy version of Cycle.js. See how to use RxJS to create simple web apps, and how to separate logic from effects.