mirror of
https://github.com/kay-is/react-from-zero.git
synced 2026-04-24 03:00:06 -04:00
111 lines
3.4 KiB
HTML
111 lines
3.4 KiB
HTML
<!doctype html>
|
|
|
|
<title>11 Lifecycle Methods - React From Zero</title>
|
|
|
|
<script src="https://unpkg.com/react@16.4.0/umd/react.development.js"></script>
|
|
<script src="https://unpkg.com/react-dom@16.4.0/umd/react-dom.development.js"></script>
|
|
<script src="https://unpkg.com/create-react-class@15.6.3/create-react-class.js"></script>
|
|
<script src="https://unpkg.com/@babel/standalone/babel.min.js"></script>
|
|
|
|
<div id="app"></div>
|
|
|
|
<script type="text/babel">
|
|
// If we use component classes, our components inherit
|
|
// a bunch of methods, which get called by React at specific
|
|
// times to allow us to get more control over our components
|
|
// a few of them we already met in lesson 9
|
|
// Here are a few new ones. Not all, but the most important ones
|
|
|
|
var TRANSLATION_FROM_SOMEWHERE = "Text from a synchronous source.";
|
|
|
|
var MyComponent = createReactClass({
|
|
// This method is for default prop values
|
|
// it gets called before the props are given to our component
|
|
// the "real" props override them if there are any
|
|
getDefaultProps: function() {
|
|
return {
|
|
iGetOverriden: "default",
|
|
iStayAsIAm: "default"
|
|
};
|
|
},
|
|
|
|
// This method is called before a component got mounted to the DOM
|
|
// it returns values that are used for this.state
|
|
getInitialState: function() {
|
|
return { serverData: null };
|
|
},
|
|
|
|
// This method gets called right before the component is mounted
|
|
// can be used to initialize some synchronous configuration, that
|
|
// should be available before the component renders
|
|
componentWillMount: function() {
|
|
this.TEXT = TRANSLATION_FROM_SOMEWHERE;
|
|
},
|
|
|
|
// This method will be called right after the component got mounted
|
|
// it's a good place to start some asynchronous tasks.
|
|
// For example on the first mount it shows a loading message
|
|
// then componentDidMount is called and gets some server data.
|
|
componentDidMount: function() {
|
|
var component = this;
|
|
|
|
// We clean up the data and get new from somewhere
|
|
function loadData() {
|
|
component.setState({ serverData: null });
|
|
|
|
getServerData(function(data) {
|
|
component.setState({ serverData: data });
|
|
});
|
|
}
|
|
|
|
// Initial data load
|
|
loadData();
|
|
|
|
// We simulate a server request every 4 seconds
|
|
this.updateInterval = setInterval(loadData, 4000);
|
|
},
|
|
|
|
// This method will be called before the component gets removed from
|
|
// the DOM a bit like a destructor. Here we can do some cleanup.
|
|
componentWillUnmount: function() {
|
|
clearInterval(this.updateInterval);
|
|
},
|
|
|
|
// This method is called before a render when new props or state is
|
|
// available. It won't be called on the first render or if
|
|
// this.forceUpdate() is used. It can be used if some state or prop
|
|
// changes don"t require a rerender.
|
|
shouldComponentUpdate: function(nextProps, nextState) {
|
|
// we want to render on every change, this is the default behavior
|
|
return true;
|
|
},
|
|
|
|
render: function() {
|
|
return (
|
|
<h2 style={{ width: 400, margin: "auto" }}>
|
|
Overriden Prop: {this.props.iGetOverriden}
|
|
<br />
|
|
<br />
|
|
Default Prop: {this.props.iStayAsIAm}
|
|
<br />
|
|
<br />
|
|
{this.TEXT}
|
|
<br />
|
|
<br />
|
|
{this.state.serverData ? this.state.serverData : "Loading..."}
|
|
</h2>
|
|
);
|
|
}
|
|
});
|
|
|
|
function getServerData(fn) {
|
|
setTimeout(function() {
|
|
fn("Data Loaded!");
|
|
}, 700);
|
|
}
|
|
|
|
ReactDOM.render(
|
|
<MyComponent iGetOverriden={"override"} />,
|
|
document.getElementById("app")
|
|
);
|
|
</script> |