Bug Report

Ionic version: [x] 4.11.3

Current behavior: When binding the pager directive if an ion-slides component to a variable, the pager will disappear if the variable changes to false, but not reappear when the bound value changes to true again.

Expected behavior: I should be able to enable and disable the page indicator programmatically and it should hide and reappear properly.

Steps to reproduce:

• Create an <ion-slides> with some slide elements and bind [pager]="someVar".
• Set someVar to true by default
• Observe the pager being visible
• Change the bound value programmatically to false.
• Observe the pager disappearing as expected.
• Change the bound value programmatically to true again.
• Observe the pager not re-appearing, which to me is unexpected behaviour

Related code:

Based on the Ionic 4 Tab sample Stackblitz and the Ionic 4 conference app I have created the following example: https://stackblitz.com/edit/ionic-v4-angular-tabs-hbeqta

Other information:

Ionic info:

Ionic:

   Ionic CLI                     : 5.4.15 (/Users/Wilk/.nvm/versions/node/v10.16.3/lib/node_modules/ionic)
   Ionic Framework               : @ionic/angular 4.11.9
   @angular-devkit/build-angular : 0.801.3
   @angular-devkit/schematics    : 8.1.3
   @angular/cli                  : 8.1.3
   @ionic/angular-toolkit        : 2.1.2

Cordova:

   Cordova CLI       : 9.0.0 (cordova-lib@9.0.1)
   Cordova Platforms : ios 5.1.1
   Cordova Plugins   : cordova-plugin-ionic-keyboard 2.2.0, cordova-plugin-ionic-webview 4.1.3, (and 4 other plugins)

Utility:

   cordova-res : 0.8.1
   native-run  : 0.3.0

System:

   ios-deploy : 1.9.4
   ios-sim    : 8.0.2
   NodeJS     : v10.16.3 (/Users/Wilk/.nvm/versions/node/v10.16.3/bin/node)
   npm        : 6.9.0
   OS         : macOS Catalina
   Xcode      : Xcode 11.3.1 Build version 11C504