bug: certain tab methods missing on framework integrations

[znotdead]

Bug Report

Ionic version:

[x] 4.11.5

Current behavior:
this.tabs.getTab is not a function

Expected behavior:
getTab should return tab component

Steps to reproduce:
on page with tabs:
@ViewChild(IonTabs, { static: false }) tabs: IonTabs;
And run this code:

const currentTab = this.tabs.getSelected();
console.log(this.tabs.getTab(currentTab));

This gives error: ERROR TypeError: "this.tabs.getTab is not a function"
In console:
error TS2339: Property 'getTab' does not exist on type 'IonTabs'.

According to docs: https://ionicframework.com/docs/api/tabs :

getTab
--
Get a specific tab by the value of its tab property or an element reference.
getTab(tab: string \| HTMLIonTabElement) => Promise<HTMLIonTabElement \| undefined>

Related code:

const currentTab = this.tabs.getSelected();
console.log(this.tabs.getTab(currentTab));

Other information:

Ionic info:

Ionic:

   Ionic CLI                     : 5.4.2
   Ionic Framework               : @ionic/angular 4.11.5
   @angular-devkit/build-angular : 0.803.8
   @angular-devkit/schematics    : 8.3.8
   @angular/cli                  : 8.3.19
   @ionic/angular-toolkit        : 2.0.0

Cordova:

   Cordova CLI       : 9.0.0 (cordova-lib@9.0.1)
   Cordova Platforms : ios 5.0.1
   Cordova Plugins   : cordova-plugin-ionic-keyboard 2.1.3, cordova-plugin-ionic-webview 4.1.0, (and 8 other plugins)

Utility:

   cordova-res : not installed
   native-run  : not installed

System:

   Android SDK Tools : 26.1.1 
   NodeJS            : v12.13.0 
   npm               : 6.12.0
   OS                : Linux 4.15

[liamdebeasi]

Thanks for the issue. What are you hoping to be able to do with getTab? We weren’t clear of the benefit of it in Angular apps, so we didn’t expose it there. We’re willing to add it but would like to understand the use case first.

[znotdead]

I have a page with tabs.
Situation: Page1 has opened Tab1.
When navigate away from Page1 there are lifecycle events fired up.
I do have Page1 ionViewWillLeave but do not have Tab1 ionViewWillLeave.
so I tried to do on Page1 ionViewWillLeave event:

• getSelected tab
• if it's tab that I'm interested in than getTab to get component
• call methods for this tab that should be fired on Tab1 ionViewWillLeave.

Of course I do not need getTab if during navigation to another page the next will be called:

1. Tab1 ionViewWillLeave
2. Page1 ionViewWillLeave
   as I'm leaving 2 pages ( Page1 and Tab1) in the same time.

[liamdebeasi]

Apologies for the delay. Thanks for the follow up. Would you be able to provide a repo with you use case that we could debug?

[znotdead]

Yes sure
https://github.com/TimberTracks/ionic_tabs_example.
To try it out. When you have a menu. You may open some tabs but it will not fire ionWillLeave if you go to another page from menu.

About will Leave. about.page.ts:17:12
Tabs will Enter. tabs.page.ts:13:12
Tab1 will Leave. tab1.page.ts:17:12
Tab2 will Enter. tab2.page.ts:14:12
Tabs will Leave. tabs.page.ts:17:12
About will Enter. about.page.ts:13:12

Tab2 will Enter. tab2.page.ts:14:12
HERE SHOULD BE Tab2 will Leave
Tabs will Leave. tabs.page.ts:17:12
About will Enter. about.page.ts:13:12