@td-design/rn-hooks/lib/commonjs/usePrevious/index.js

从ahooks里面抽取的一些在rn项目里可以使用的hooks。提高开发效率

'use strict';

var react = require('react');

var defaultShouldUpdate = function (a, b) { return !Object.is(a, b); };
/**
 * 保存上一次状态的 Hook。
 * @param state 初始state
 * @param shouldUpdate 判断是否更新的函数
 */
function usePrevious(state, shouldUpdate) {
    if (shouldUpdate === void 0) { shouldUpdate = defaultShouldUpdate; }
    var prevRef = react.useRef();
    var currentRef = react.useRef();
    if (shouldUpdate(currentRef.current, state)) {
        prevRef.current = currentRef.current;
        currentRef.current = state;
    }
    return prevRef.current;
}

module.exports = usePrevious;