GT2/GT2-Android/node_modules/react-native/Libraries/Interaction/Batchinator.js

78 lines
2.3 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule Batchinator
* @flow
*/
'use strict';
const InteractionManager = require('InteractionManager');
/**
* A simple class for batching up invocations of a low-pri callback. A timeout is set to run the
* callback once after a delay, no matter how many times it's scheduled. Once the delay is reached,
* InteractionManager.runAfterInteractions is used to invoke the callback after any hi-pri
* interactions are done running.
*
* Make sure to cleanup with dispose(). Example:
*
* class Widget extends React.Component {
* _batchedSave: new Batchinator(() => this._saveState, 1000);
* _saveSate() {
* // save this.state to disk
* }
* componentDidUpdate() {
* this._batchedSave.schedule();
* }
* componentWillUnmount() {
* this._batchedSave.dispose();
* }
* ...
* }
*/
class Batchinator {
_callback: () => void;
_delay: number;
_taskHandle: ?{cancel: () => void};
constructor(callback: () => void, delayMS: number) {
this._delay = delayMS;
this._callback = callback;
}
/*
* Cleanup any pending tasks.
*
* By default, if there is a pending task the callback is run immediately. Set the option abort to
* true to not call the callback if it was pending.
*/
dispose(options: {abort: boolean} = {abort: false}) {
if (this._taskHandle) {
this._taskHandle.cancel();
if (!options.abort) {
this._callback();
}
this._taskHandle = null;
}
}
schedule() {
if (this._taskHandle) {
return;
}
const timeoutHandle = setTimeout(() => {
this._taskHandle = InteractionManager.runAfterInteractions(() => {
// Note that we clear the handle before invoking the callback so that if the callback calls
// schedule again, it will actually schedule another task.
this._taskHandle = null;
this._callback();
});
}, this._delay);
this._taskHandle = {cancel: () => clearTimeout(timeoutHandle)};
}
}
module.exports = Batchinator;