Provide fallback for new AlertDialog

Summary:
In D57019423, the `AlertFragment` started using the `AlertDialog` from androidx. This could potentially trigger an `IllegalStateException` if an alert is displayed from an activity that does not have theming from AppCompat.

This diff provides a fallback to the original `android.app.AlertDialog` if the current activity is not an AppCompat descendant. In addition, it modifies the test case to ensure that the alert dialog still displays and can be dismissed

Differential Revision: D57113950

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/modules/dialog/AlertFragment.java

@@ -11,6 +11,7 @@
 import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
+import android.content.res.TypedArray;
 import android.os.Bundle;
 import androidx.annotation.Nullable;
 import androidx.appcompat.app.AlertDialog;
@@ -40,6 +41,30 @@ public AlertFragment(@Nullable DialogModule.AlertFragmentListener listener, Bund
 
   public static Dialog createDialog(
       Context activityContext, Bundle arguments, DialogInterface.OnClickListener fragment) {
+    if (isAppCompatTheme(activityContext)) {
+      return createAppCompatDialog(activityContext, arguments, fragment);
+    } else {
+      return createAppDialog(activityContext, arguments, fragment);
+    }
+  }
+
+  /**
+   * Checks if the current activity is a descendant of an AppCompat theme.
+   *
+   * @returns true if the current activity is a descendant of an AppCompat theme.
+   */
+  private static boolean isAppCompatTheme(Context activityContext) {
+    TypedArray attributes =
+        activityContext.obtainStyledAttributes(androidx.appcompat.R.styleable.AppCompatTheme);
+    return attributes.hasValue(androidx.appcompat.R.styleable.AppCompatTheme_windowActionBar);
+  }
+
+  /**
+   * Creates a dialog compatible only with AppCompat activities. This function should be kept in
+   * sync with {@link createAppDialog}.
+   */
+  private static Dialog createAppCompatDialog(
+      Context activityContext, Bundle arguments, DialogInterface.OnClickListener fragment) {
     AlertDialog.Builder builder =
         new AlertDialog.Builder(activityContext).setTitle(arguments.getString(ARG_TITLE));
 
@@ -64,6 +89,39 @@ public static Dialog createDialog(
     return builder.create();
   }
 
+  /**
+   * Creates a dialog compatible with non-AppCompat activities. This function should be kept in sync
+   * with {@link createAppCompatDialog}.
+   *
+   * @deprecated non-AppCompat dialogs are deprecated and will be removed in a future version.
+   */
+  private static Dialog createAppDialog(
+      Context activityContext, Bundle arguments, DialogInterface.OnClickListener fragment) {
+    android.app.AlertDialog.Builder builder =
+        new android.app.AlertDialog.Builder(activityContext)
+            .setTitle(arguments.getString(ARG_TITLE));
+
+    if (arguments.containsKey(ARG_BUTTON_POSITIVE)) {
+      builder.setPositiveButton(arguments.getString(ARG_BUTTON_POSITIVE), fragment);
+    }
+    if (arguments.containsKey(ARG_BUTTON_NEGATIVE)) {
+      builder.setNegativeButton(arguments.getString(ARG_BUTTON_NEGATIVE), fragment);
+    }
+    if (arguments.containsKey(ARG_BUTTON_NEUTRAL)) {
+      builder.setNeutralButton(arguments.getString(ARG_BUTTON_NEUTRAL), fragment);
+    }
+    // if both message and items are set, Android will only show the message
+    // and ignore the items argument entirely
+    if (arguments.containsKey(ARG_MESSAGE)) {
+      builder.setMessage(arguments.getString(ARG_MESSAGE));
+    }
+    if (arguments.containsKey(ARG_ITEMS)) {
+      builder.setItems(arguments.getCharSequenceArray(ARG_ITEMS), fragment);
+    }
+
+    return builder.create();
+  }
+
   @Override
   public Dialog onCreateDialog(Bundle savedInstanceState) {
     return createDialog(getActivity(), getArguments(), this);

packages/react-native/ReactAndroid/src/test/java/com/facebook/react/modules/dialog/DialogModuleTest.kt

@@ -47,35 +47,14 @@ class DialogModuleTest {
 
   @Before
   fun setUp() {
-    activityController = Robolectric.buildActivity(FragmentActivity::class.java)
-    activity = activityController.create().start().resume().get()
-    // We must set the theme to a descendant of AppCompat for the AlertDialog to show without
-    // raising an exception
-    activity.setTheme(APP_COMPAT_THEME)
-
-    val context: ReactApplicationContext = mock(ReactApplicationContext::class.java)
-    whenever(context.hasActiveReactInstance()).thenReturn(true)
-    whenever(context.currentActivity).thenReturn(activity)
-
-    dialogModule = DialogModule(context)
-    dialogModule.onHostResume()
+    setupActivity()
   }
 
   @After
   fun tearDown() {
     activityController.pause().stop().destroy()
   }
 
-  @Test
-  fun testIllegalActivityTheme() {
-    val options = JavaOnlyMap()
-    activity.setTheme(NON_APP_COMPAT_THEME)
-
-    assertThrows(NullPointerException::class.java) { dialogModule.showAlert(options, null, null) }
-
-    activity.setTheme(APP_COMPAT_THEME)
-  }
-
   @Test
   fun testAllOptions() {
     val options =
@@ -168,6 +147,39 @@ class DialogModuleTest {
     assertEquals(DialogModule.ACTION_DISMISSED, actionCallback.args!![0])
   }
 
+  @Test
+  fun testNonAppCompatActivityTheme() {
+    setupActivity(NON_APP_COMPAT_THEME)
+
+    val options = JavaOnlyMap()
+
+    val actionCallback = SimpleCallback()
+    dialogModule.showAlert(options, null, actionCallback)
+    shadowOf(getMainLooper()).idle()
+
+    getFragment()!!.dialog!!.dismiss()
+    shadowOf(getMainLooper()).idle()
+
+    assertEquals(1, actionCallback.calls)
+    assertEquals(DialogModule.ACTION_DISMISSED, actionCallback.args!![0])
+  }
+
+  private fun setupActivity(theme: Int = APP_COMPAT_THEME) {
+    activityController = Robolectric.buildActivity(FragmentActivity::class.java)
+    activity = activityController.create().start().resume().get()
+
+    // We must set the theme to a descendant of AppCompat for the AlertDialog to show without
+    // raising an exception
+    activity.setTheme(theme)
+
+    val context: ReactApplicationContext = mock(ReactApplicationContext::class.java)
+    whenever(context.hasActiveReactInstance()).thenReturn(true)
+    whenever(context.currentActivity).thenReturn(activity)
+
+    dialogModule = DialogModule(context)
+    dialogModule.onHostResume()
+  }
+
   private fun getFragment(): AlertFragment? {
     return activity.supportFragmentManager.findFragmentByTag(DialogModule.FRAGMENT_TAG)
         as? AlertFragment