XHP-JS
XHP-JS is a combination of Hack and Javascript libraries allowing you to easily call Javascript functions or create Javascript classes that from XHP components, and to pass these classes or references to the DOM nodes to other Javascript code.
For convenience, an interface to construct React components is also included.
A short overview is available at https://code.facebook.com/posts/858739974205250
Examples
A full example is available at https://github.com/hhvm/xhp-js-example
Calling a Javascript function
class :example:jscall extends :x:element {
use XHPHelpers;
use XHPJSCall;
attribute :xhp:html-element;
protected function render(): XHPRoot {
$this->jsCall(
'ModuleName',
'functionName',
'First argument',
// This pases the DOM node corresponding to the <div /> below
XHPJS::Element($this),
'Third arugment',
);
return <div id={$this->getID()} />;
}
}
print
<html><head /><body>
<x:js-scope><example:js-call /><x:js-scope>
</body></html>;Creating a Javascript Object
class :example:jsinstance extends :x:element {
use XHPHelpers;
use XHPJSCall;
attribute :xhp:html-element;
protected function render(): XHPRoot {
$this->constructJSInstance(
'ClassName',
XHPJS::Element($this),
// can pass through other arguments too
);
$this->jsCall(
'MyModule',
'myFunction',
// This passes the JS object created above
XHPJS::Instance($this),
);
return <div id={$this->getID()} />;
}
}
print
<html><head /><body>
<x:js-scope><example:js-instance /><x:js-scope>
</body></html>;Creating a React component
class :example:typeahead extends :x:element implements XHPAwaitable {
use XHPHelpers;
use XHPReact;
use XHPAsync;
attribute :xhp:html-element;
protected async function asyncRender(): Awaitable<XHPRoot> {
$friend_names = await FriendsList::fetch($this->getContext('Viewer'));
$this->constructReactInstance(
'ReactTypeahead',
Map { 'friends' => $friend_names },
);
return <div id={$this->getID()} />;
}
}
print
<html><head /><body>
<x:js-scope><example:typeahead /><x:js-scope>
</body></html>;Writing your JavaScript
We recommend writing your modules as CommonJS modules, and using Browserify.
Alternatively, you can create them as members of the window object.
XHP-JS looks for modules as members of the window object, and falls back to attempting to call 'require("ModuleName")' - this requires a require() function to be defined in the global scope.
For example:
$this->jsCall('MyModule', 'myMethod', 'argument');This Hack code can be thought of as creating the following Javascript:
var module = window.MyModule ? window.MyModule : require('MyModule');
module.myMethod('argument');In turn, your JavaScript may look like:
var MyModule = {
myFunction: function() {
// ...
}
};
module.exports = MyModule; // if using CommonJS + Browserify
window.MyModule = MyModule; // if notInstallation
We recommend installing XHP-JS with Composer (for the Hack code) and npm + Browserify for the Javascript code. Alternatively, you can include xhpjs.js or xhpjs.min.js directly to declare an XHPJS object in the global scope.
See https://github.com/hhvm/xhp-js-example for a full example.
License
XHP-JS is BSD-licensed. We also provide an additional patent grant.
