Create basic back button (HD-28)

src/components/AppLayout/AppLayout.styles.tsx

@@ -57,6 +57,10 @@ export const styles = (theme: Theme) =>
                 display: "none"
             }
         },
+        appBarBackButton: {
+            marginLeft: -12,
+            marginRight: 20
+        },
         appBarTitle: {
             display: "none",
             [theme.breakpoints.up("md")]: {

src/components/AppLayout/AppLayout.tsx

@@ -44,6 +44,7 @@ import SupervisedUserCircleIcon from "@material-ui/icons/SupervisedUserCircle";
 import ExitToAppIcon from "@material-ui/icons/ExitToApp";
 import TrendingUpIcon from "@material-ui/icons/TrendingUp";
 import BuildIcon from "@material-ui/icons/Build";
+import ArrowBackIcon from "@material-ui/icons/ArrowBack";
 
 import { styles } from "./AppLayout.styles";
 import { MultiAccount, UAccount } from "../../types/Account";
@@ -67,6 +68,7 @@ import {
     getAccountRegistry,
     removeAccountFromRegistry
 } from "../../utilities/accounts";
+import { isChildView } from "../../utilities/appbar";
 
 interface IAppLayoutState {
     acctMenuOpen: boolean;
@@ -484,6 +486,17 @@ export class AppLayout extends Component<any, IAppLayoutState> {
                     {this.titlebar()}
                     <AppBar className={classes.appBar} position="static">
                         <Toolbar>
+                            {isChildView(window.location.hash) ? (
+                                <IconButton
+                                    className={classes.appBarBackButton}
+                                    color="inherit"
+                                    aria-label="Go back"
+                                    onClick={() => window.history.back()}
+                                >
+                                    <ArrowBackIcon />
+                                </IconButton>
+                            ) : null}
+
                             <IconButton
                                 className={classes.appBarMenuButton}
                                 color="inherit"

src/utilities/appbar.tsx

@@ -9,3 +9,20 @@ import { isDarwinApp } from "./desktop";
 export function isAppbarExpanded(): boolean {
     return isDarwinApp() || process.env.NODE_ENV === "development";
 }
+
+/**
+ * Determine whether the current page is a child view and can go back.
+ */
+export function isChildView(hash: string): boolean {
+    const childViews = ["#/conversation", "#/profile"];
+    let foundProtocol = false;
+
+    childViews.forEach((childViewProtocol: string) => {
+        if (hash.includes(childViewProtocol)) {
+            console.log(childViewProtocol);
+            foundProtocol = true;
+        }
+    });
+
+    return foundProtocol;
+}