Add background task for Android

android/app/build.gradle

@@ -47,6 +47,8 @@ dependencies {
     implementation project(':capacitor-cordova-android-plugins')
 
     implementation "com.google.firebase:firebase-crashlytics:18.2.13"
+    implementation 'androidx.work:work-runtime:2.9.0'
+    implementation 'com.google.guava:guava:29.0-android'
 }
 
 apply from: 'capacitor.build.gradle'

android/app/capacitor.build.gradle

@@ -23,7 +23,6 @@ dependencies {
     implementation project(':capacitor-share')
     implementation project(':capacitor-status-bar')
     implementation project(':capacitor-cloudkit')
-
 }
 
 

android/app/src/main/java/app/getbaseline/baseline/MainActivity.java

@@ -15,24 +15,32 @@
 
 import androidx.appcompat.app.AlertDialog;
 import androidx.webkit.WebViewCompat;
+import androidx.work.ExistingPeriodicWorkPolicy;
+import androidx.work.PeriodicWorkRequest;
+import androidx.work.WorkManager;
 
 import com.getcapacitor.BridgeActivity;
 
+import java.util.concurrent.TimeUnit;
+
 public class MainActivity extends BridgeActivity {
     final String WEBVIEW_PACKAGE = "com.google.android.webview";
 
     @Override
     public void onStart() {
         super.onStart();
+        // Force dark mode based on UI mode
         int nightModeFlags = getResources().getConfiguration().uiMode & Configuration.UI_MODE_NIGHT_MASK;
         WebSettings webSettings = this.bridge.getWebView().getSettings();
         if (nightModeFlags == Configuration.UI_MODE_NIGHT_YES && Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
             webSettings.setForceDark(WebSettings.FORCE_DARK_ON);
         }
 
+        // Disable weird accessibility text scaling
         WebSettings settings = this.bridge.getWebView().getSettings();
         settings.setTextZoom(100);
 
+        // Show update notice if WebView is too old
         SharedPreferences prefs = bridge.getActivity().getPreferences(Context.MODE_PRIVATE);
         PackageInfo webViewInfo = WebViewCompat.getCurrentWebViewPackage(bridge.getContext());
 
@@ -44,7 +52,7 @@ public void onStart() {
                         .setTitle("Warning")
                         .setMessage("You have an old version of Android WebView installed, which will " +
                                 "cause significant display issues on baseline since it's what we use to display the app. " +
-                                "Click below to go the Google Play Store and update 'Android System WebView' to fix this.")
+                                "Click below to go to the Google Play Store and update 'Android System WebView' to fix this.")
                         .setPositiveButton("Open Play Store", new DialogInterface.OnClickListener() {
                             @Override
                             public void onClick(DialogInterface dialogInterface, int i) {
@@ -66,6 +74,17 @@ public void onClick(DialogInterface dialogInterface, int i) {
                         .setCanceledOnTouchOutside(false);
             }
         }
+
+        // Schedule background notification clearing
+        PeriodicWorkRequest request =
+                new PeriodicWorkRequest.Builder(NotificationWorker.class,
+                        30, TimeUnit.MINUTES,
+                        30, TimeUnit.MINUTES)
+                        .build();
+
+        WorkManager.getInstance(bridge.getContext())
+                .enqueueUniquePeriodicWork("app.getbaseline.baseline.notifications",
+                    ExistingPeriodicWorkPolicy.UPDATE, request);
      }
 
     @Override

android/app/src/main/java/app/getbaseline/baseline/NotificationWorker.java

@@ -0,0 +1,48 @@
+package app.getbaseline.baseline;
+
+import android.app.NotificationManager;
+import android.content.Context;
+import android.service.notification.StatusBarNotification;
+
+import androidx.annotation.NonNull;
+import androidx.work.Worker;
+import androidx.work.WorkerParameters;
+
+import java.util.ArrayList;
+
+public class NotificationWorker extends Worker {
+    public NotificationWorker(@NonNull Context context, @NonNull WorkerParameters workerParams) {
+        super(context, workerParams);
+    }
+
+    @NonNull
+    @Override
+    public Result doWork() {
+        // For some reason, you can only pull delivered notifications at Android M,
+        //  so it's only worth running any of this if we're at that SDK level
+        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
+            // Find the latest notification in all delivered notifications
+            NotificationManager notificationManager = getApplicationContext().getSystemService(NotificationManager.class);
+            ArrayList<StatusBarNotification> notifs = new ArrayList<>();
+            StatusBarNotification latestNotif = null;
+            for (StatusBarNotification notif : notificationManager.getActiveNotifications()) {
+                notifs.add(notif);
+                if (latestNotif == null || latestNotif.getPostTime() < notif.getPostTime()) {
+                    latestNotif = notif;
+                }
+            }
+
+            // Remove the latest from the list of all delivered
+            if (latestNotif != null) {
+                notifs.remove(latestNotif);
+            }
+
+            // And remove all other notifications
+            for (StatusBarNotification notif : notifs) {
+                notificationManager.cancel(notif.getTag(), notif.getId());
+            }
+        }
+
+        return Result.success();
+    }
+}