Add a ToastStore

To store toast. Rather than them being stored in the state of the
ToastContainer component, they now have a dedicated store. This mostly
fixes problems involving showing toasts when the app loaded because
we would otherwise have a race condition where something tries to
show a toast before the ToastContainer is mounted.

src/components/structures/MatrixChat.js

@@ -64,6 +64,7 @@ import { ThemeWatcher } from "../../theme";
 import { storeRoomAliasInCache } from '../../RoomAliasCache';
 import { defer } from "../../utils/promise";
 import KeyVerificationStateObserver from '../../utils/KeyVerificationStateObserver';
+import ToastStore from "../../stores/ToastStore";
 
 /** constants for MatrixChat.state.view */
 export const VIEWS = {
@@ -1458,15 +1459,12 @@ export default createReactClass({
                 }
 
                 if (!requestObserver || requestObserver.pending) {
-                    dis.dispatch({
-                        action: "show_toast",
-                        toast: {
-                            key: request.event.getId(),
+                    ToastStore.sharedInstance().addOrReplaceToast({
+                        key: 'verifreq_' + request.event.getId(),
                         title: _t("Verification Request"),
                         icon: "verification",
                         props: {request, requestObserver},
                         component: sdk.getComponent("toasts.VerificationRequestToast"),
-                        },
                     });
                 }
             });

src/components/structures/ToastContainer.js

@@ -1,5 +1,5 @@
 /*
-Copyright 2019 The Matrix.org Foundation C.I.C.
+Copyright 2019, 2020 The Matrix.org Foundation C.I.C.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -15,8 +15,8 @@ limitations under the License.
 */
 
 import * as React from "react";
-import dis from "../../dispatcher";
 import { _t } from '../../languageHandler';
+import ToastStore from "../../stores/ToastStore";
 import classNames from "classnames";
 
 export default class ToastContainer extends React.Component {
@@ -26,26 +26,15 @@ export default class ToastContainer extends React.Component {
     }
 
     componentDidMount() {
-        this._dispatcherRef = dis.register(this.onAction);
+        ToastStore.sharedInstance().on('update', this._onToastStoreUpdate);
     }
 
     componentWillUnmount() {
-        dis.unregister(this._dispatcherRef);
+        ToastStore.sharedInstance().removeListener('update', this._onToastStoreUpdate);
     }
 
-    onAction = (payload) => {
-        if (payload.action === "show_toast") {
-            this._addToast(payload.toast);
-        }
-    };
-
-    _addToast(toast) {
-        this.setState({toasts: this.state.toasts.concat(toast)});
-    }
-
-    dismissTopToast = () => {
-        const [, ...remaining] = this.state.toasts;
-        this.setState({toasts: remaining});
+    _onToastStoreUpdate = () => {
+        this.setState({toasts: ToastStore.sharedInstance().getToasts()});
     };
 
     render() {
@@ -62,8 +51,8 @@ export default class ToastContainer extends React.Component {
             const countIndicator = isStacked ? _t(" (1/%(totalCount)s)", {totalCount}) : null;
 
             const toastProps = Object.assign({}, props, {
-                dismiss: this.dismissTopToast,
                 key,
+                toastKey: key,
             });
             toast = (<div className={toastClasses}>
                 <h2>{title}{countIndicator}</h2>

src/components/views/toasts/VerificationRequestToast.js

@@ -23,6 +23,7 @@ import {MatrixClientPeg} from '../../../MatrixClientPeg';
 import {verificationMethods} from 'matrix-js-sdk/src/crypto';
 import KeyVerificationStateObserver, {userLabelForEventRoom} from "../../../utils/KeyVerificationStateObserver";
 import dis from "../../../dispatcher";
+import ToastStore from "../../../stores/ToastStore";
 
 export default class VerificationRequestToast extends React.PureComponent {
     constructor(props) {
@@ -63,12 +64,12 @@ export default class VerificationRequestToast extends React.PureComponent {
 
     _checkRequestIsPending = () => {
         if (!this.props.requestObserver.pending) {
-            this.props.dismiss();
+            ToastStore.sharedInstance().dismissToast(this.props.toastKey);
         }
     }
 
     cancel = () => {
-        this.props.dismiss();
+        ToastStore.sharedInstance().dismissToast(this.props.toastKey);
         try {
             this.props.request.cancel();
         } catch (err) {
@@ -77,7 +78,7 @@ export default class VerificationRequestToast extends React.PureComponent {
     }
 
     accept = () => {
-        this.props.dismiss();
+        ToastStore.sharedInstance().dismissToast(this.props.toastKey);
         const {event} = this.props.request;
         // no room id for to_device requests
         if (event.getRoomId()) {
@@ -119,7 +120,7 @@ export default class VerificationRequestToast extends React.PureComponent {
 }
 
 VerificationRequestToast.propTypes = {
-    dismiss: PropTypes.func.isRequired,
     request: PropTypes.object.isRequired,
     requestObserver: PropTypes.instanceOf(KeyVerificationStateObserver),
+    toastKey: PropTypes.string.isRequired,
 };

src/stores/ToastStore.js

@@ -0,0 +1,52 @@
+/*
+Copyright 2020 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import EventEmitter from 'events';
+
+/**
+ * Holds the active toasts
+ */
+export default class ToastStore extends EventEmitter {
+    static sharedInstance() {
+        if (!global.mx_ToastStore) global.mx_ToastStore = new ToastStore();
+        return global.mx_ToastStore;
+    }
+
+    constructor() {
+        super();
+        this._dispatcherRef = null;
+        this._toasts = [];
+    }
+
+    addOrReplaceToast(newToast) {
+        const oldIndex = this._toasts.findIndex(t => t.key === newToast.key);
+        if (oldIndex === -1) {
+            this._toasts.push(newToast);
+        } else {
+            this._toasts[oldIndex] = newToast;
+        }
+        this.emit('update');
+    }
+
+    dismissToast(key) {
+        this._toasts = this._toasts.filter(t => t.key !== key);
+        this.emit('update');
+    }
+
+    getToasts() {
+        return this._toasts;
+    }
+}