Relay share intents through a headless activity

android/app/src/main/AndroidManifest.xml

@@ -27,17 +27,6 @@
         <action android:name="android.intent.action.MAIN"/>
         <category android:name="android.intent.category.LAUNCHER"/>
       </intent-filter>
-      <!-- Share target. Without this filter the app never appears in the
-           system share sheet at all; image/* only, the editor takes photos.
-           Goes on the launcher activity: it is singleTask, so a share
-           re-delivered there replaces its intent (onNewIntent -> setIntent)
-           and the running app picks the photo up without a cold start. -->
-      <intent-filter>
-        <action android:name="android.intent.action.SEND"/>
-        <action android:name="android.intent.action.SEND_MULTIPLE"/>
-        <category android:name="android.intent.category.DEFAULT"/>
-        <data android:mimeType="image/*"/>
-      </intent-filter>
       <intent-filter>
         <action android:name="android.intent.action.VIEW"/>
         <category android:name="android.intent.category.DEFAULT"/>
@@ -45,5 +34,19 @@
         <data android:scheme="exp+recipescamera"/>
       </intent-filter>
     </activity>
+    <!-- Share target. Without this filter the app never appears in the
+         system share sheet at all; image/* only, the editor takes photos.
+         A separate no-display relay, not MainActivity: a host app that starts
+         the target without FLAG_ACTIVITY_NEW_TASK would otherwise drop the
+         editor into its own task and the share would look like part of it.
+         ShareActivity relaunches MainActivity in our own task instead. -->
+    <activity android:name=".ShareActivity" android:theme="@android:style/Theme.NoDisplay" android:launchMode="standard" android:excludeFromRecents="true" android:exported="true">
+      <intent-filter>
+        <action android:name="android.intent.action.SEND"/>
+        <action android:name="android.intent.action.SEND_MULTIPLE"/>
+        <category android:name="android.intent.category.DEFAULT"/>
+        <data android:mimeType="image/*"/>
+      </intent-filter>
+    </activity>
   </application>
 </manifest>

android/app/src/main/java/com/locphamtran/recipescamera/ShareActivity.kt

@@ -0,0 +1,30 @@
+package com.locphamtran.recipescamera
+
+import android.app.Activity
+import android.content.Intent
+import android.os.Bundle
+
+/**
+ * Share sheet entry point for SEND / SEND_MULTIPLE.
+ *
+ * A host app that starts us without FLAG_ACTIVITY_NEW_TASK drops the started
+ * activity into its own task, so the editor used to show up as a screen of that
+ * app (it lived in that app's stack, back returned there). MainActivity cannot
+ * fix that itself: bailing out in onCreate would either boot React twice or skip
+ * super.onCreate and crash onDestroy.
+ *
+ * So the share filters live here. This activity never draws (NoDisplay theme):
+ * it hands the same intent to MainActivity with NEW_TASK — singleTask then routes
+ * it to our own task, or re-delivers it to the running instance — and finishes.
+ * The editor is therefore always a task of its own.
+ */
+class ShareActivity : Activity() {
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+    startActivity(
+        Intent(intent)
+            .setClass(this, MainActivity::class.java)
+            .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK))
+    finish()
+  }
+}