xatto
xatto is View Layer Library based on Function and Context using VirtualDOM.
This is developed by forking from jorgebucaran/superfine.
Getting Started
Note: The example in this document assumes that you are using a JavaScript compiler such as Babel or TypeScript, a JSX (TSX) transpiler, and a module bundle such as Parcel, Webpack.
The main APIs of xatto
are two.
The first one is xatto.x
. It returns a new virtual DOM node tree.
The other is xatto.atto
. It returns a function that mount (or update) a component in the specified DOM element. (mutate
function)
example: A counter that can be incremented or decremented.
import x atto from "xatto" const down = count: contextcount - 1 const up = count: contextcount + 1 const Component = props children context <div> <h1>contextcount</h1> <button =>-</button> <button =>+</button> </div> count: 10
Installation
xatto is available as a package on npm.
npm install xatto
It is also available on a CDN.
Easier
git clone https://github.com/atomita/xatto-starter-kit.git projectcd projectnpm installnpm run serve
Overview
Context
A context is a JavaScript object that describes a component.
It consists of dynamic data that moves within a component during execution.
To change the context you need to use the mutate function (or event handler in the components).
Mutate function
It is a function returned by xatto.atto
.
Passing the context mount the component specified by xatto.atto on the specified container together.
From the second time on, it update.
Components
The component returns the specification in the form of a plain JavaScript object called virtual DOM, and xatto is updates the actual DOM accordingly.
Each time the context changes the component is invoked so you can specify the appearance of the DOM based on the new context.
The context can be referenced in the third arguments.
import x atto from "xatto" const Component = props children context <div>contextname</div> name: "foo"
Fragments supported
const Component = props children <> <div>foo</div> <div>bar</div> </>
Sliced context and fill
The child component can treat a part of the context as if it were the root context by using <Context slice="path">
in the parent component.
Also, the fill
attribute can specify a value to use if part of the sliced context is undefined.
import x atto Context from "xatto" const Parent = props children context <div> <span>contextname</span> <ul> <li><Context ="children.0"><Child /></Context></li> <li><Context ="children.1" =><Child /></Context></li> </ul> </div> const Child = props children context <span>contextname</span> name: "foo" children: 0: name: "bar"
Events
Event handlers are wrapped by xatto.
Usually, the event object passed in the first argument is the fourth argument.
The return value is passed to the mutate function.
Event handler arguments:
- context
{ ...extra, ...detail, dispatch }
detail
is CustomEvent.detaildispatch
is function for dispatch a CustomEvent
- props
- event
Lifecycle Events
Lifecycle events can be used to be notified when an element managed by the virtual DOM is created, updated, or deleted.
It can be used for animation, data fetching, third party library wrapping, resource cleanup, etc.
oncreate
This event occurs after an element is created and attached to the DOM.
onupdate
This event will occur each time you update an element's attributes.
onremove
This event occurs before an element is dettached from the DOM.
detail.done
is passed a function to detach the element.
ondestroy
This event occurs just before an element is dettached from the DOM.
onlifecycle
This event occurs just before each life cycle event occurs.
detail.type
is passed the life cycle event name.
Keys
The key helps to identify the node each time xatto update the DOM.
This allows you to rearrange the elements to a new position if you change the position.
The key must be unique among sibling nodes.
Extra
If you want to pass values from the parent component to all descendant components, try using Extra
.
You can refer to the same value regardless of context
.
import x atto Context Extra from "xatto" const Parent = props children context <div> <span>contextname</span> <Extra => <ul> <li><Context ="children.child1"><Child /></Context></li> <li><Context ="children.child2" =><Child /></Context></li> </ul> </Extra> </div> const Child = props children context extra <div> <p>extraparentName + ' - ' + contextname</p> contextchildren && Object </div> const Grandchild = props children context extra <p>extraparentName + ' - ' + contextname</p> name: "foo" children: child1: name: "bar" children: grandChild1: name: "barbaz"
Polyfill which may be needed
License
xatto is MIT licensed. See LICENSE.
Other examples
The counters.
import x atto Context from "xatto" const down = count: contextcount - 1 const up = count: contextcount + 1 const Counter = props children context <div> <h1>contextcount</h1> <button =>-</button> <button =>+</button> </div> let idx = 2 const add = counters: ...contextcounters ...Object const cut = { const entry = Object0 if entry == null return delete contextcountersentry0 return counters: ...contextcounters } const Main = props children context <div> <button =>add</button> <button =>cut</button> Object <pre>JSON</pre> </div> counters: 0: count: 0 1: count: 10