react-native/Libraries/Components/LazyRenderer.js

44 lines
968 B
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @providesModule LazyRenderer
*/
'use strict';
const React = require('React');
const createReactClass = require('create-react-class');
const PropTypes = require('prop-types');
const TimerMixin = require('react-timer-mixin');
const LazyRenderer = createReactClass({
displayName: 'LazyRenderer',
mixin: [TimerMixin],
propTypes: {
render: PropTypes.func.isRequired,
},
UNSAFE_componentWillMount: function(): void {
this.setState({
_lazyRender : true,
});
},
componentDidMount: function(): void {
requestAnimationFrame(() => {
this.setState({
_lazyRender : false,
});
});
},
render: function(): ?React.Element {
return this.state._lazyRender ? null : this.props.render();
},
});
module.exports = LazyRenderer;