got rid of the the deprecated PreferencesActivity.onBackPressed()

app/src/main/AndroidManifest.xml

@@ -15,6 +15,7 @@
 	</queries>
 
 	<application
+		android:enableOnBackInvokedCallback="true"
 		android:icon="@mipmap/ic_launcher"
 		android:roundIcon="@mipmap/ic_launcher_round"
 		android:label="@string/app_name"

app/src/main/java/io/github/sspanak/tt9/preferences/PreferencesActivity.java

@@ -3,6 +3,7 @@ package io.github.sspanak.tt9.preferences;
 import android.content.Intent;
 import android.os.Bundle;
 
+import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.ActionBar;
@@ -52,6 +53,7 @@ public class PreferencesActivity extends ActivityWithNavigation implements Prefe
 		validateFunctionKeys();
 
 		super.onCreate(savedInstanceState);
+		setOnBackPressed();
 
 		// changing the theme causes onCreate(), which displays the MainSettingsScreen,
 		// but leaves the old "back" history, which is no longer valid,
@@ -98,20 +100,26 @@ public class PreferencesActivity extends ActivityWithNavigation implements Prefe
 	}
 
 
-	@Override
+	/**
-	public void onBackPressed() {
+	 * onBackPressed() is deprecated, so calling the onBackPressed() on the Fragments is now more complicated.
-		Fragment previousFragment = getSupportFragmentManager().findFragmentById(R.id.preferences_container);
+	 */
-		if (previousFragment instanceof BaseScreenFragment) {
+	private void setOnBackPressed() {
-			((BaseScreenFragment) previousFragment).onBackPressed();
+		OnBackPressedCallback onBackPressedCallback = new OnBackPressedCallback(true) {
-		}
+			@Override
+			public void handleOnBackPressed() {
+				Fragment previousFragment = getSupportFragmentManager().findFragmentById(R.id.preferences_container);
+				if (previousFragment instanceof BaseScreenFragment) {
+					((BaseScreenFragment) previousFragment).onBackPressed();
+				}
 
-		super.onBackPressed();
+				setEnabled(false);
+				getOnBackPressedDispatcher().onBackPressed();
+				setEnabled(true);
+			}
+    };
 
-		Fragment nextFragment = getSupportFragmentManager().findFragmentById(R.id.preferences_container);
+		// On API >= 33, this requires android:enableOnBackInvokedCallback="true" in the manifest
-		if (nextFragment instanceof BaseScreenFragment) {
+		getOnBackPressedDispatcher().addCallback(this, onBackPressedCallback);
-			((BaseScreenFragment) nextFragment).onBackPressed();
-			getOptionsCount = ((BaseScreenFragment) nextFragment)::getPreferenceCount;
-		}
 	}
 
 

app/src/main/java/io/github/sspanak/tt9/preferences/screens/BaseScreenFragment.java

@@ -66,6 +66,7 @@ abstract public class BaseScreenFragment extends PreferenceFragmentCompat {
 	public void onResume() {
 		super.onResume();
 		setScreenTitle();
+		setActivityOptionCounter();
 	}
 
 
@@ -86,6 +87,13 @@ abstract public class BaseScreenFragment extends PreferenceFragmentCompat {
 	}
 
 
+	private void setActivityOptionCounter() {
+		if (activity != null) {
+			activity.setOptionsCount(this::getPreferenceCount);
+		}
+	}
+
+
 	public void resetFontSize(boolean reloadList) {
 		initPreferencesList();
 		preferencesList.getAll(reloadList, true);

app/src/main/java/io/github/sspanak/tt9/ui/ActivityWithNavigation.java

@@ -79,6 +79,11 @@ abstract public class ActivityWithNavigation extends EdgeToEdgeActivity {
 	}
 
 
+	public void setOptionsCount(@NonNull Callable<Integer> getOptionsCount) {
+		this.getOptionsCount = getOptionsCount;
+	}
+
+
 	protected void resetKeyRepeat() {
 		lastKey = KeyEvent.KEYCODE_UNKNOWN;
 	}