Refactor: Introduce SyntaxFabActivity to reduce boilerplate

This commit introduces a new abstract base class, `SyntaxFabActivity`, to encapsulate the common behavior of the "Show Syntax" Floating Action Button (FAB). This FAB, used across many lesson activities, now has its click handling and auto-shrink logic managed within this shared base class.

Key changes:
- Created `SyntaxFabActivity` which handles the FAB's `setOnClickListener` and the 5-second auto-shrink `postDelayed` logic.
- Migrated numerous lesson activities to extend `SyntaxFabActivity` instead of `UpNavigationActivity`, replacing duplicated Handler and click listener code with a single call to the new `setupSyntaxFab` method.
- Updated the Room dependency to version 2.8.2.

Author: MihaiCristianCondrea

app/src/main/java/com/d4rk/androidtutorials/java/ui/components/navigation/SyntaxFabActivity.java

@@ -0,0 +1,37 @@
+package com.d4rk.androidtutorials.java.ui.components.navigation;
+
+import android.os.Handler;
+import android.os.Looper;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
+import com.google.android.material.floatingactionbutton.ExtendedFloatingActionButton;
+
+/**
+ * Base activity that encapsulates the common pattern of wiring a syntax FAB that shrinks after
+ * a short delay. A large portion of the lesson detail screens use the same behaviour which was
+ * previously duplicated in every activity.
+ */
+public abstract class SyntaxFabActivity extends UpNavigationActivity {
+
+    private static final long DEFAULT_SHRINK_DELAY_MS = 5000L;
+
+    private final Handler syntaxFabHandler = new Handler(Looper.getMainLooper());
+
+    protected final void setupSyntaxFab(@Nullable ExtendedFloatingActionButton fab,
+                                        @NonNull Runnable onClick) {
+        if (fab == null) {
+            return;
+        }
+
+        fab.setOnClickListener(view -> onClick.run());
+        syntaxFabHandler.postDelayed(fab::shrink, DEFAULT_SHRINK_DELAY_MS);
+    }
+
+    @Override
+    protected void onDestroy() {
+        syntaxFabHandler.removeCallbacksAndMessages(null);
+        super.onDestroy();
+    }
+}

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/alerts/alertdialog/AlertDialogActivity.java

@@ -2,18 +2,14 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
-
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.databinding.ActivityAlertDialogBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 
-public class AlertDialogActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class AlertDialogActivity extends SyntaxFabActivity {
     private ActivityAlertDialogBinding binding;
 
     @Override
@@ -25,13 +21,11 @@ protected void onCreate(Bundle savedInstanceState) {
         MaterialAlertDialogBuilder alertDialog = createAlertDialog();
         binding.button.setOnClickListener(v -> alertDialog.show());
 
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "AlertDialog");
             startActivity(intent);
         });
-
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
     }
 
     private MaterialAlertDialogBuilder createAlertDialog() {
@@ -42,11 +36,4 @@ private MaterialAlertDialogBuilder createAlertDialog() {
                 .setPositiveButton(android.R.string.ok, null)
                 .setNegativeButton(android.R.string.cancel, null);
     }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
-    }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/alerts/snackbar/SnackBarActivity.java

@@ -2,18 +2,14 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
-
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.databinding.ActivitySnackBarBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 import com.google.android.material.snackbar.Snackbar;
 
-public class SnackBarActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class SnackBarActivity extends SyntaxFabActivity {
     private ActivitySnackBarBinding binding;
 
     @Override
@@ -28,19 +24,10 @@ protected void onCreate(Bundle savedInstanceState) {
             snackbar.show();
         });
 
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "SnackBar");
             startActivity(intent);
         });
-
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
-    }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
     }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/alerts/toast/ToastActivity.java

@@ -2,18 +2,15 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
 import android.widget.Toast;
 
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.databinding.ActivityToastBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 
-public class ToastActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class ToastActivity extends SyntaxFabActivity {
     private ActivityToastBinding binding;
 
     @Override
@@ -27,19 +24,10 @@ protected void onCreate(Bundle savedInstanceState) {
                 Toast.makeText(this, R.string.toast_this_is_a_toast, Toast.LENGTH_SHORT).show()
         );
 
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "Toast");
             startActivity(intent);
         });
-
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
-    }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
     }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/buttons/buttons/ButtonsActivity.java

@@ -1,13 +1,10 @@
 package com.d4rk.androidtutorials.java.ui.screens.android.lessons.buttons.buttons;
 
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
-
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.ads.AdUtils;
 import com.d4rk.androidtutorials.java.databinding.ActivityButtonsBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.lessons.buttons.buttons.tabs.ButtonsTabCodeFragment;
 import com.d4rk.androidtutorials.java.ui.screens.android.lessons.buttons.buttons.tabs.ButtonsTabLayoutFragment;
 import com.d4rk.androidtutorials.java.ui.screens.android.lessons.common.LessonCodeTabsActivity;
@@ -17,8 +14,7 @@
 import me.zhanghai.android.fastscroll.FastScrollerBuilder;
 import java.util.Arrays;
 
-public class ButtonsActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class ButtonsActivity extends SyntaxFabActivity {
     private ActivityButtonsBinding binding;
 
     @Override
@@ -52,7 +48,7 @@ protected void onCreate(Bundle savedInstanceState) {
         binding.floatingButtonSecondary.setOnClickListener(view -> Snackbar.make(binding.getRoot(), getString(R.string.floating_button_secondary_icon) + " " + getString(R.string.snack_bar_clicked), Snackbar.LENGTH_SHORT).show());
         binding.floatingButtonSurface.setOnClickListener(view -> Snackbar.make(binding.getRoot(), getString(R.string.floating_button_surface_icon) + " " + getString(R.string.snack_bar_clicked), Snackbar.LENGTH_SHORT).show());
         binding.floatingButtonTertiary.setOnClickListener(view -> Snackbar.make(binding.getRoot(), getString(R.string.floating_button_tertiary_icon) + " " + getString(R.string.snack_bar_clicked), Snackbar.LENGTH_SHORT).show());
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> startActivity(
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> startActivity(
                 LessonCodeTabsActivity.createIntent(
                         ButtonsActivity.this,
                         R.string.buttons,
@@ -67,13 +63,5 @@ protected void onCreate(Bundle savedInstanceState) {
                                 )
                         )
                 )));
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
-    }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
     }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/buttons/image/ImageButtonsActivity.java

@@ -2,19 +2,15 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
-
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.ads.AdUtils;
 import com.d4rk.androidtutorials.java.databinding.ActivityImageButtonsBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 import com.google.android.material.snackbar.Snackbar;
 
-public class ImageButtonsActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class ImageButtonsActivity extends SyntaxFabActivity {
     private ActivityImageButtonsBinding binding;
 
     @Override
@@ -33,19 +29,10 @@ protected void onCreate(Bundle savedInstanceState) {
                 Snackbar.make(binding.getRoot(), R.string.snack_image_button, Snackbar.LENGTH_SHORT).show()
         );
 
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "ImageButtons");
             startActivity(intent);
         });
-
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
-    }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
     }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/buttons/radio/RadioButtonsActivity.java

@@ -2,19 +2,16 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
 import android.util.SparseArray;
 
 import com.d4rk.androidtutorials.java.databinding.ActivityRadioButtonsBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 import com.google.android.material.radiobutton.MaterialRadioButton;
 import com.google.android.material.snackbar.Snackbar;
 
-public class RadioButtonsActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class RadioButtonsActivity extends SyntaxFabActivity {
     private ActivityRadioButtonsBinding binding;
 
     @Override
@@ -35,19 +32,10 @@ protected void onCreate(Bundle savedInstanceState) {
             }
         });
 
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "RadioButtons");
             startActivity(intent);
         });
-
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
-    }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
     }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/buttons/switches/SwitchActivity.java

@@ -2,21 +2,17 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
-
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.ads.AdUtils;
 import com.d4rk.androidtutorials.java.databinding.ActivitySwitchBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 import com.google.android.material.snackbar.Snackbar;
 
 import me.zhanghai.android.fastscroll.FastScrollerBuilder;
 
-public class SwitchActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class SwitchActivity extends SyntaxFabActivity {
     private ActivitySwitchBinding binding;
 
     @Override
@@ -40,18 +36,10 @@ private void setOnClickListeners() {
         binding.materialSwitch.setOnClickListener(view -> Snackbar.make(binding.getRoot(), R.string.material_switch, Snackbar.LENGTH_SHORT).show());
         binding.switchMaterial.setOnClickListener(view -> Snackbar.make(binding.getRoot(), R.string.switch_material, Snackbar.LENGTH_SHORT).show());
         binding.buttonToggle.setOnClickListener(view -> Snackbar.make(binding.getRoot(), R.string.toggle_button, Snackbar.LENGTH_SHORT).show());
-        binding.floatingButtonShowSyntax.setOnClickListener(view -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "Switch");
             startActivity(intent);
         });
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
-    }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
     }
 }

app/src/main/java/com/d4rk/androidtutorials/java/ui/screens/android/lessons/clocks/chronometer/ChronometerActivity.java

@@ -2,21 +2,18 @@
 
 import android.content.Intent;
 import android.os.Bundle;
-import android.os.Handler;
-import android.os.Looper;
 import android.os.SystemClock;
 
 import androidx.annotation.Nullable;
 
 import com.d4rk.androidtutorials.java.R;
 import com.d4rk.androidtutorials.java.ads.AdUtils;
 import com.d4rk.androidtutorials.java.databinding.ActivityChronometerBinding;
-import com.d4rk.androidtutorials.java.ui.components.navigation.UpNavigationActivity;
+import com.d4rk.androidtutorials.java.ui.components.navigation.SyntaxFabActivity;
 import com.d4rk.androidtutorials.java.ui.screens.android.CodeActivity;
 import com.d4rk.androidtutorials.java.utils.EdgeToEdgeHelper;
 
-public class ChronometerActivity extends UpNavigationActivity {
-    private final Handler handler = new Handler(Looper.getMainLooper());
+public class ChronometerActivity extends SyntaxFabActivity {
     private ActivityChronometerBinding binding;
 
     @Override
@@ -32,21 +29,13 @@ protected void onCreate(@Nullable Bundle savedInstanceState) {
         binding.descriptionSection.descriptionText.setText(R.string.summary_chronometer);
         AdUtils.loadBanner(binding.descriptionSection.adView);
 
-        binding.floatingButtonShowSyntax.setOnClickListener(v -> {
+        setupSyntaxFab(binding.floatingButtonShowSyntax, () -> {
             Intent intent = new Intent(this, CodeActivity.class);
             intent.putExtra("lesson_name", "Chronometer");
             startActivity(intent);
         });
-        handler.postDelayed(() -> binding.floatingButtonShowSyntax.shrink(), 5000);
         binding.buttonStart.setOnClickListener(v -> binding.chronometer.start());
         binding.buttonStop.setOnClickListener(v -> binding.chronometer.stop());
         binding.buttonReset.setOnClickListener(v -> binding.chronometer.setBase(SystemClock.elapsedRealtime()));
     }
-
-
-    @Override
-    protected void onDestroy() {
-        super.onDestroy();
-        handler.removeCallbacksAndMessages(null);
-    }
 }