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@ionic/core

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/*! * (C) Ionic http://ionicframework.com - MIT License */ import { w as win } from './index5.js'; import { c as config } from './ionic-global.js'; /** * CloseWatcher is a newer API that lets * use detect the hardware back button event * in a web browser: https://caniuse.com/?search=closewatcher * However, not every browser supports it yet. * * This needs to be a function so that we can * check the config once it has been set. * Otherwise, this code would be evaluated the * moment this file is evaluated which could be * before the config is set. */ const shouldUseCloseWatcher = () => config.get('experimentalCloseWatcher', false) && win !== undefined && 'CloseWatcher' in win; /** * When hardwareBackButton: false in config, * we need to make sure we also block the default * webview behavior. If we don't then it will be * possible for users to navigate backward while * an overlay is still open. Additionally, it will * give the appearance that the hardwareBackButton * config is not working as the page transition * will still happen. */ const blockHardwareBackButton = () => { document.addEventListener('backbutton', () => { }); // eslint-disable-line }; const startHardwareBackButton = () => { const doc = document; let busy = false; const backButtonCallback = () => { if (busy) { return; } let index = 0; let handlers = []; const ev = new CustomEvent('ionBackButton', { bubbles: false, detail: { register(priority, handler) { handlers.push({ priority, handler, id: index++ }); }, }, }); doc.dispatchEvent(ev); const executeAction = async (handlerRegister) => { try { if (handlerRegister === null || handlerRegister === void 0 ? void 0 : handlerRegister.handler) { const result = handlerRegister.handler(processHandlers); if (result != null) { await result; } } } catch (e) { console.error(e); } }; const processHandlers = () => { if (handlers.length > 0) { let selectedHandler = { priority: Number.MIN_SAFE_INTEGER, handler: () => undefined, id: -1, }; handlers.forEach((handler) => { if (handler.priority >= selectedHandler.priority) { selectedHandler = handler; } }); busy = true; handlers = handlers.filter((handler) => handler.id !== selectedHandler.id); executeAction(selectedHandler).then(() => (busy = false)); } }; processHandlers(); }; /** * If the CloseWatcher is defined then * we don't want to also listen for the native * backbutton event otherwise we may get duplicate * events firing. */ if (shouldUseCloseWatcher()) { let watcher; const configureWatcher = () => { watcher === null || watcher === void 0 ? void 0 : watcher.destroy(); watcher = new win.CloseWatcher(); /** * Once a close request happens * the watcher gets destroyed. * As a result, we need to re-configure * the watcher so we can respond to other * close requests. */ watcher.onclose = () => { backButtonCallback(); configureWatcher(); }; }; configureWatcher(); } else { doc.addEventListener('backbutton', backButtonCallback); } }; const OVERLAY_BACK_BUTTON_PRIORITY = 100; const MENU_BACK_BUTTON_PRIORITY = 99; // 1 less than overlay priority since menu is displayed behind overlays export { MENU_BACK_BUTTON_PRIORITY, OVERLAY_BACK_BUTTON_PRIORITY, blockHardwareBackButton, shouldUseCloseWatcher, startHardwareBackButton };