Develop Reference

Ionic Capacitor hardware back button is automatically closing the app

My current setup is:
#capacitor/core: 3.0.0,
#ionic-native/core: 5.0.7
I'm trying to change the behavior of my app to not close the app, but go back in the navigation stack. To my knowledge, the hardware back button on Android devices did not automatically close the app until I upgraded Capacitor to 3.0.0
What is confusing me though, is how I have absolutely 0 code for handling the back button functionality, and from everything I'm searching online shows the back button doing nothing by default, not automatically closing the app as the default (as mine seems to be doing). I've searched all the project files for anything to do with "platform", "backButton", and "App.Exit" and was unable to find any code that may be causing the app to close.
I've tried subscribing to the back button press event using the below code and it is never ran. The app closes instead of showing the alert dialog. I've changed the priority from 0, 10, and 99 (all priorities listed in the Ionic documentation)
this.platform.backButton.subscribeWithPriority(10, () => {
alert('Back button pressed!');
});

Install capacitor app.
npm install #capacitor/app
Import it.
import { App as CapacitorApp } from '#capacitor/app';
Add back listener if can go back then we can push to back or exit the app.
CapacitorApp.addListener('backButton', ({canGoBack}) => {
if(!canGoBack){
CapacitorApp.exitApp();
} else {
window.history.back();
}
});

So, I feel a bit dumb after realizing this, but it is because I had to run the below commands, because I apparently didn't update them when upgrading Capacitor a while back. Make sure all of your plugins are fully updated, yours may be different than mine.
npm install #capacitor/app
npx cap sync

I had the same issue and I tried installing all the plugins like it says here
npm install #capacitor/app #capacitor/haptics #capacitor/keyboard #capacitor/status-bar
After I finished installing, I still got the error. Also my PushNotifications plugin was not working either.
My problem was I forgot to delete the OnCreate method from MainActivity.java. So if you still have the problem after installing the plugins, try to delete OnCreate method so your MainActivity.java looks like this:
public class MainActivity extends BridgeActivity {}
See more here.
It also fixed my PushNotifications plugin.
If I understand it correctly, if you have any plugin that is not registered correctly, it will cause this kind of error. This answer also helped me.

https://stackoverflow.com/a/69084017/19086322
This post work really good for me !!
Before this post i made these commands and after it worked:
npm install #capacitor/app
npx cap sync

I have the same issue and adding #capacitor/app to my App worked for debugging puposes. The Problem is, when I build a release app, it still closes the app.
--- EDIT ---
I fixed the issue by building a completely new Ionic App (with the latest versions of everything) and then copying my code.
I assume it really had something to do with the installed versions of the Ionic and Capacitor packages

You need to use below code to handle the Hardware back button in Ionic app:
//back button handle
//Registration of push in Android and Windows Phone
let lastTimeBackPress: number = 0;
let timePeriodToExit: number = 2000;
platform.registerBackButtonAction(() => {
//Double check to exit app
if (new Date().getTime() - lastTimeBackPress < timePeriodToExit) {
//this.platform.exitApp(); //Exit from app
this.appMinimize.minimize().then(() => {
console.log('minimized successfully');
});
} else {
this.toastCtrl.create({
message: this.translate.instant('EXIT_APP_MESSAGE'),
duration: 3000,
position: 'bottom'
}).present();
lastTimeBackPress = new Date().getTime();
}
});

for android:
import android.webkit.WebView;
import com.getcapacitor.BridgeActivity;
public class MainActivity extends BridgeActivity {
//in my case I call it the JS function when I press the back button
#Override
public void onBackPressed() {
WebView webView = getBridge().getWebView();
webView.loadUrl("javascript:pressBack()");
// in Index.html create tag
//<script type="text/javascript">
// function pressBack(){
// alert('yes!!')
// }
//</script>
return;
}
}

Ionic 4: Hardware Back Button Reloading Application

Working on a Project and stuck in an Issue:
Hardware Back Button Reloading Application (I am using Angular Router in this application).
My Code to Exit Application:
ionViewDidEnter(){
this.subscription = this.platform.backButton.subscribe(()=>{
navigator['app'].exitApp();
});
}
ionViewWillLeave(){
this.subscription.unsubscribe();
}
While same logic Working in other applications. but in this application its reloading the application not exiting it.
P.S: i have also tried it to put in platform.ready() but no luck.

With IONIC 4, there is new method subscribeWithPriority developed to handle race between soft & hard back button. Try modifying your code like below:
this.platform.backButton.subscribeWithPriority(1, () => {
navigator['app'].exitApp();
});
subscribeWithPriority() stops the propagation of the event after its execution and if we subscribe with high priority and execute our prefered navigation instead of default one then it is going to work as you want.
More reference docs for details:
https://github.com/ionic-team/ionic/commit/6a5aec8b5d76280ced5e8bb8fd9ea6fe75fe6795
https://medium.com/#aleksandarmitrev/ionic-hardware-back-button-nightmare-9f4af35cbfb0
UPDATES:
Try using this new version of exitApp cordova plugin. I haven't
tried myself but looks promising from popularity.
Also try to empty the page stack from Navcontroller or go to your home screen, seems like that's causing the reload for app with sidemenu's & tab pages... this.navCtrl.pop() / this._navCtrl.navigateBack('HomeScreen'), and then call exitApp.
NOTE: Tabs & SideMenu as those have its own routing module does create lot of complexity with app navigation.

Solved:
As Mention by #rtpHarry template of SideMenu / Tabs have History which leads application to Reload it self on root page. i was able to solve this by clearing History.
ionViewDidEnter(){
navigator['app'].clearHistory();
}
on Your Root Page just Clear your history and your Hardware Back Button will close the Application instead of Reloading it.

Do you have a sidemenu in your app? I'm just curious because this seems to be when I get this problem as well.
If you look in your inspector, you will see that window.history has a length of 1.
I don't see it in some of my apps, but the app that I have a side menu setup acts this way - on the homepage if you press back the screen goes white then it reloads the app.
Like I say, looking in the inspector shows that there is a history to step back to, which it is trying to do, and whatever that history step is, it just pushes it forward back to the homepage, which made me wonder if it was the sidemenu setting up its own control of the navigation system.
I've probably said some poorly worded terminology but as I haven't solved this myself I thought I would just let you know what I had found... hopefully it helps you move forward.
In my scenario, I wasn't even trying to do the exit on back code - I just noticed that the app would appear to "reboot" if I kept pressing back.

This explain the solution on Ionic 5 (and 4.6+ too I think).
private backButtonSub: Subscription;
ionViewDidEnter() {
this.backButtonSub = this.platform.backButton.subscribeWithPriority(
10000,
() => {
// do your stuff
}
);
}
ionViewWillLeave() {
this.backButtonSub.unsubscribe();
}
also keep
IonicModule.forRoot({
hardwareBackButton: true
}),
to true (default) in your app.module.ts
Sources:
https://www.damirscorner.com/blog/posts/20191122-CustomizingAndroidBackButtonInIonic4.html
The Doc

Status Bar Hide Cordova

If I remove the status bar, every time I open the keyboard (
or a notification arrives) there is a bug.
App.run(function($ionicPlatform) {
$ionicPlatform.ready(function() {
if(window.StatusBar) {
StatusBar.hide();
}
});
});
Any suggestion? Thank you!

Updated:
Actually, there is a fix for cordova-plugin-statusbar that has been committed on github and should land in version 2.1.4+ (i.e. you don't need an additional plugin like my original answer stated). To get the latest cordova-plugin-statusbar now, type
cordova plugin add https://github.com/apache/cordova-plugin-statusbar.git
The statusbar should now stay hidden when interacting with inputs, keyboard etc.
Original Answer:
I fixed it with the plugin cordova-plugin-fullscreen
cordova plugin add cordova-plugin-fullscreen
Then, after deviceready:
StatusBar.hide();
if (typeof AndroidFullScreen !== 'undefined') { // Fullscreen plugin exists ?
function errorFunction(error) { console.error(error); }
AndroidFullScreen.isSupported(AndroidFullScreen.immersiveMode, errorFunction);
}
ImmersiveMode keeps it hidden while interacting with inputs, keyboard etc.
Note: as per the cordova-plugin-fullscreen docs, this method is only supported on Android 4.4+. There is also a 'lean mode' for Android 4.0+, but this shows the status bar while interacting (not ideal)

$ionic.Platform.ready not firing in android

I currently have the $ionicPlatform event listener in my app.js. I know it's working in the test environment on the pc browser, but when I build the app and run it on my android device, the ionicPlatform.ready never actually runs/fires. Any ideas?
Here are some threads/questions posted, with some solutions that haven't worked for me.
https://github.com/driftyco/ionic/issues/1751
https://stackoverflow.com/questions/32421291/code-inside-ionic-platform-ready-not-getting-fired-up
app.js
var app = angular.module('who', ['ionic', 'ngCordova'])
.run(function($ionicPlatform, $rootScope, $cordovaDevice) {
$ionicPlatform.ready(function() {
if(window.cordova && window.cordova.plugins.Keyboard) {
// Hide the accessory bar by default (remove this to show the accessory bar above the keyboard
// for form inputs)
cordova.plugins.Keyboard.hideKeyboardAccessoryBar(true);
// Don't remove this line unless you know what you are doing. It stops the viewport
// from snapping when text inputs are focused. Ionic handles this internally for
// a much nicer keyboard experience.
cordova.plugins.Keyboard.disableScroll(true);
}
if(window.StatusBar) {
StatusBar.styleDefault();
}
var push = new Ionic.Push({
"debug": true
});
push.register(function(token) {
console.log("Device token:",token.token);
});
console.log('reached end of ionic platform ready');
});
})
UPDATE 12/14/2015 # 5:24 AM - I have a view/activity that loads first, it renders the results from the $ionic.platform.ready listener. Upon loading the app, it renders nothing. What's interesting is this, after going to another view/activity, and then going back to the first view/activity, the result is then loaded/rendered. Any ideas?
UPDATE 12/14/2015 # 5:30 AM - I have tried ionic.Platform.ready, I have tried the document.addEventlistener 'deviceready'. None of them are working, and $ionicPlatform.ready gives me the least amount of problems, so I have defaulted to that.

I've decided to go with this workaround for now, unless someone can refactor this better for me.
The data retrieved in the $ionicPlatform.ready would not be rendered in the first activity loaded. I would usually have to navigate to at least 1 more activity and then go back to see the results. Now I know ionicFramework has it's own default splash activity that I don't want to override for this purpose (for now), so I added another view/state/activity that just serves as a buffer and immediately navigates to the results activity.
app loaded <- the ionic platform ready should be fired here, but it doesn't
ionic splash activity
buffer activity
result activity <- ionic platform ready finally fires up, weird.
Could just be my misunderstanding of Ionic's data synchronization, but this dirty fix seems to have solved it.

Phonegap window.open does not work on Android

I have an iOS/Android app built on cordova 2.6 and jqm 1.3. I need to open a link to an external website after the user clicks on a button. The code I am using is:
var ref = window.open('http://google.com','_self','location=yes');
ref.addEventListener('loadstart',function(event) {
console.log('load started');
});
ref.addEventListener('loadstop',function(event) {
console.log('load stopped');
});
ref.addEventListener('loaderror',function(event) {
console.log('load error = ' + JSON.stringify(event));
});
On iOS everything performs like I would expect. A new browser window opens with the google website loaded. But I cannot get anything to to load in Android. When I click on the button, nothing happens. I have put in console statements before and after the window.open, so I know the code is at least being executed.
My config.xml should be wide open for white listed sites:
<access origin=".*"/>;
I have tested on a Nexus 7 (android 4.2) and an android 2.2 emulator with the same results on both.
Does anyone know why window.open would not be firing correctly on android?

It looked like it was a problem with 2.6 loading plugins on Android. I upgraded to 2.7 and everything started to work.

Perhaps it's a solution to use the ChildBrowser plugin? This gives you a bit more control over the operation itself, while still preserving platform compatibility between iOS and Android.
In most cases, I use something like the following snippet to use the childbrowser to display an external page.
function openBrowser(url) {
// determine if the childbrowser plugin is available
var useChildBrowser = ('plugins' in window && window.plugins.childBrowser);
if (useChildBrowser) {
popup = window.plugins.childBrowser;
popup.showWebPage(url, { showLocationBar: false, showAddress: false });
} else {
popup = window.open(url, 'Share', "['width=600px', 'height=400px', 'resizable=0', 'fullscreen=yes']");
}
}
Note that this falls back to using window.open if the ChildBrowser plugin isn't available, so you won't break anything else with this. Could be worth a shot, perhaps?