feat(react): Add IonTabsContext to add some missing element methods, closes #19935 (#21171)

packages/react/src/components/index.ts

@@ -18,6 +18,7 @@ export { IonPopover } from './IonPopover';
 
 // Custom Components
 export { IonPage } from './IonPage';
+export { IonTabsContext, IonTabsContextState } from './navigation/IonTabsContext';
 export { IonTabs } from './navigation/IonTabs';
 export { IonTabBar } from './navigation/IonTabBar';
 export { IonBackButton } from './navigation/IonBackButton';

packages/react/src/components/navigation/IonTabBar.tsx

@@ -5,28 +5,33 @@ import { NavContext } from '../../contexts/NavContext';
 import { IonicReactProps } from '../IonicReactProps';
 import { IonTabBarInner } from '../inner-proxies';
 import { IonTabButton } from '../proxies';
+import { createForwardRef } from '../utils';
 
-type Props = LocalJSX.IonTabBar & IonicReactProps & {
+type IonTabBarProps = LocalJSX.IonTabBar & IonicReactProps & {
-  onIonTabsDidChange?: (event: CustomEvent<{ tab: string }>) => void;
+  onIonTabsDidChange?: (event: CustomEvent<{ tab: string; }>) => void;
-  onIonTabsWillChange?: (event: CustomEvent<{ tab: string }>) => void;
+  onIonTabsWillChange?: (event: CustomEvent<{ tab: string; }>) => void;
   currentPath?: string;
   slot?: 'bottom' | 'top';
 };
 
+interface InternalProps extends IonTabBarProps {
+  forwardedRef?: React.RefObject<HTMLIonIconElement>;
+}
+
 interface TabUrls {
   originalHref: string;
   currentHref: string;
 }
 
-interface State {
+interface IonTabBarState {
   activeTab: string | undefined;
-  tabs: { [key: string]: TabUrls };
+  tabs: { [key: string]: TabUrls; };
 }
 
-class IonTabBarUnwrapped extends React.PureComponent<Props, State> {
+class IonTabBarUnwrapped extends React.PureComponent<InternalProps, IonTabBarState> {
   context!: React.ContextType<typeof NavContext>;
 
-  constructor(props: Props) {
+  constructor(props: InternalProps) {
     super(props);
     const tabs: { [key: string]: TabUrls; } = {};
 
@@ -39,16 +44,42 @@ class IonTabBarUnwrapped extends React.PureComponent<Props, State> {
       }
     });
 
+    const tabKeys = Object.keys(tabs);
+    const activeTab = tabKeys
+      .find(key => {
+        const href = tabs[key].originalHref;
+        return props.currentPath!.startsWith(href);
+      }) || tabKeys[0];
+
     this.state = {
-      activeTab: undefined,
+      activeTab,
       tabs
     };
 
     this.onTabButtonClick = this.onTabButtonClick.bind(this);
     this.renderTabButton = this.renderTabButton.bind(this);
+    this.setActiveTabOnContext = this.setActiveTabOnContext.bind(this);
+    this.selectTab = this.selectTab.bind(this);
   }
 
-  static getDerivedStateFromProps(props: Props, state: State) {
+  setActiveTabOnContext = (_tab: string) => { };
+
+  selectTab(tab: string) {
+    const tabUrl = this.state.tabs[tab];
+    if (tabUrl) {
+      this.onTabButtonClick(new CustomEvent('ionTabButtonClick', {
+        detail: {
+          href: tabUrl.currentHref,
+          tab,
+          selected: tab === this.state.activeTab
+        }
+      }));
+      return true;
+    }
+    return false;
+  }
+
+  static getDerivedStateFromProps(props: IonTabBarProps, state: IonTabBarState) {
 
     const tabs = { ...state.tabs };
     const activeTab = Object.keys(state.tabs)
@@ -101,6 +132,7 @@ class IonTabBarUnwrapped extends React.PureComponent<Props, State> {
       if (this.props.onIonTabsDidChange) {
         this.props.onIonTabsDidChange(new CustomEvent('ionTabDidChange', { detail: { tab: e.detail.tab } }));
       }
+      this.setActiveTabOnContext(e.detail.tab);
       this.context.navigate(currentHref, 'none');
     }
   }
@@ -120,9 +152,7 @@ class IonTabBarUnwrapped extends React.PureComponent<Props, State> {
   }
 
   render() {
-
     const { activeTab } = this.state;
-
     return (
       <IonTabBarInner {...this.props} selectedTab={activeTab}>
         {React.Children.map(this.props.children as any, this.renderTabButton(activeTab))}
@@ -135,10 +165,11 @@ class IonTabBarUnwrapped extends React.PureComponent<Props, State> {
   }
 }
 
-export const IonTabBar: React.FC<Props> = React.memo<Props>(props => {
+const IonTabBarContainer: React.FC<InternalProps> = React.memo<InternalProps>(({ forwardedRef, ...props }) => {
   const context = useContext(NavContext);
   return (
     <IonTabBarUnwrapped
+      ref={forwardedRef}
       {...props as any}
       currentPath={props.currentPath || context.currentPath}
     >
@@ -146,3 +177,5 @@ export const IonTabBar: React.FC<Props> = React.memo<Props>(props => {
     </IonTabBarUnwrapped>
   );
 });
+
+export const IonTabBar = createForwardRef<IonTabBarProps, HTMLIonTabBarElement>(IonTabBarContainer, 'IonTabBar');

packages/react/src/components/navigation/IonTabs.tsx

@@ -1,13 +1,16 @@
 import { JSX as LocalJSX } from '@ionic/core';
-import React from 'react';
+import React, { Fragment } from 'react';
 
 import { NavContext } from '../../contexts/NavContext';
 import { IonRouterOutlet } from '../IonRouterOutlet';
 
 import { IonTabBar } from './IonTabBar';
+import { IonTabsContext, IonTabsContextState } from './IonTabsContext';
+
+type ChildFunction = (ionTabContext: IonTabsContextState) => React.ReactNode;
 
 interface Props extends LocalJSX.IonTabs {
-  children: React.ReactNode;
+  children: ChildFunction | React.ReactNode;
 }
 
 const hostStyles: React.CSSProperties = {
@@ -32,25 +35,60 @@ const tabsInner: React.CSSProperties = {
 export class IonTabs extends React.Component<Props> {
   context!: React.ContextType<typeof NavContext>;
   routerOutletRef: React.Ref<HTMLIonRouterOutletElement> = React.createRef();
+  selectTabHandler?: (tag: string) => boolean;
+  tabBarRef = React.createRef<any>();
+
+  ionTabContextState: IonTabsContextState = {
+    activeTab: undefined,
+    selectTab: () => false
+  };
 
   constructor(props: Props) {
     super(props);
   }
 
+  componentDidMount() {
+    if (this.tabBarRef.current) {
+      // Grab initial value
+      this.ionTabContextState.activeTab = this.tabBarRef.current.state.activeTab;
+      // Override method
+      this.tabBarRef.current.setActiveTabOnContext = (tab: string) => {
+        this.ionTabContextState.activeTab = tab;
+      };
+      this.ionTabContextState.selectTab = this.tabBarRef.current.selectTab;
+    }
+  }
+
   render() {
     let outlet: React.ReactElement<{}> | undefined;
     let tabBar: React.ReactElement | undefined;
 
-    React.Children.forEach(this.props.children, (child: any) => {
+    const children = typeof this.props.children === 'function' ?
+      (this.props.children as ChildFunction)(this.ionTabContextState) : this.props.children;
+
+    React.Children.forEach(children, (child: any) => {
       if (child == null || typeof child !== 'object' || !child.hasOwnProperty('type')) {
         return;
       }
       if (child.type === IonRouterOutlet) {
         outlet = child;
+      } else if (child.type === Fragment && child.props.children[0].type === IonRouterOutlet) {
+        outlet = child.props.children[0];
       }
       if (child.type === IonTabBar) {
         const { onIonTabsDidChange, onIonTabsWillChange } = this.props;
-        tabBar = React.cloneElement(child, { onIonTabsDidChange, onIonTabsWillChange });
+        tabBar = React.cloneElement(child, {
+          onIonTabsDidChange,
+          onIonTabsWillChange,
+          ref: this.tabBarRef
+        });
+      } else if (child.type === Fragment && child.props.children[1].type === IonTabBar) {
+        const { onIonTabsDidChange, onIonTabsWillChange } = this.props;
+        tabBar = React.cloneElement(child.props.children[1], {
+          onIonTabsDidChange,
+          onIonTabsWillChange,
+          ref: this.tabBarRef
+        });
       }
     });
 
@@ -63,6 +101,9 @@ export class IonTabs extends React.Component<Props> {
     }
 
     return (
+      <IonTabsContext.Provider
+        value={this.ionTabContextState}
+      >
         <div style={hostStyles}>
           {tabBar.props.slot === 'top' ? tabBar : null}
           <div style={tabsInner} className="tabs-inner">
@@ -70,6 +111,7 @@ export class IonTabs extends React.Component<Props> {
           </div>
           {tabBar.props.slot === 'bottom' ? tabBar : null}
         </div>
+      </IonTabsContext.Provider >
     );
   }
 

packages/react/src/components/navigation/IonTabsContext.tsx

@@ -0,0 +1,11 @@
+import React from 'react';
+
+export interface IonTabsContextState {
+  activeTab: string | undefined;
+  selectTab: (tab: string) => boolean;
+}
+
+export const IonTabsContext = React.createContext<IonTabsContextState>({
+  activeTab: undefined,
+  selectTab: () => false
+});

packages/react/tslint.json

@@ -27,8 +27,10 @@
     "jsx-no-lambda": false,
     "jsx-no-multiline-js": false,
     "jsx-wrap-multiline": false,
+    "no-empty": false,
     "no-empty-interface": false,
     "no-unbound-method": false,
+    "no-unused-expression": false,
     "prefer-conditional-expression": false
   }
 }