Update minimum supported Android API to 33

app/src/main/java/net/moasdawiki/app/MainActivity.java

@@ -44,6 +44,8 @@ import android.widget.LinearLayout;
 import android.widget.ProgressBar;
 import android.widget.TextView;
 import android.widget.Toast;
+import android.window.OnBackInvokedCallback;
+import android.window.OnBackInvokedDispatcher;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
@@ -61,7 +63,6 @@ import net.moasdawiki.service.repository.RepositoryService;
 import net.moasdawiki.util.EscapeUtils;
 
 import java.io.ByteArrayInputStream;
-import java.io.IOException;
 import java.io.InputStream;
 import java.net.URLDecoder;
 import java.util.Arrays;
@@ -75,7 +76,7 @@ import java.util.concurrent.Executors;
 /**
  * Displays the main window with the embedded wiki browser.
  */
-public class MainActivity extends AppCompatActivity {
+public class MainActivity extends AppCompatActivity implements OnBackInvokedCallback {
 
     private static final String TAG = "MainActivity";
     private static final String SERVER_BASE_URL = "http://localhost:1/";
@@ -114,6 +115,8 @@ public class MainActivity extends AppCompatActivity {
                 return false;
             }
         });
+
+        getOnBackInvokedDispatcher().registerOnBackInvokedCallback(OnBackInvokedDispatcher.PRIORITY_DEFAULT, this);
     }
 
     /**
@@ -263,9 +266,7 @@ public class MainActivity extends AppCompatActivity {
         super.onRequestPermissionsResult(requestCode, permissions, grantResults);
     }
 
-    @Override
-    public void onBackPressed() {
-        // webview.canGoBack() always returns false
+    public void onBackInvoked() {
         WebBackForwardList backForwardList = webview.copyBackForwardList();
         Log.d(TAG, "Back button pressed, backForwardList index == " + backForwardList.getCurrentIndex());
         if (backForwardList.getCurrentIndex() > 0) {
@@ -274,7 +275,6 @@ public class MainActivity extends AppCompatActivity {
             // Close app
             finish();
         }
-        super.onBackPressed();
     }
 
     public void onConfigurationHintClicked(@SuppressWarnings("unused") View view) {