Merge pull request #499 from getbouncer/awush/update_interface

Update the interface so reference to the callback is not lost on activity killed
getbouncer · Mar 28, 2022 · f422a32 · f422a32
2 parents 454b180 + 7f66760
commit f422a32
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Showing 2 changed files with 25 additions and 17 deletions.
diff --git a/cardscan-demo/src/main/java/com/getbouncer/cardscan/demo/LaunchActivity.java b/cardscan-demo/src/main/java/com/getbouncer/cardscan/demo/LaunchActivity.java
@@ -30,7 +30,7 @@ protected void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_launch);
 
-        final CardScanSheet sheet = CardScanSheet.create(this, API_KEY);
+        final CardScanSheet sheet = CardScanSheet.create(this, API_KEY, this::handleScanResult);
 
         // Because this activity displays card numbers, disallow screenshots.
         getWindow().setFlags(
@@ -52,8 +52,7 @@ protected void onCreate(@Nullable Bundle savedInstanceState) {
             sheet.present(
                 /* enableEnterCardManually */ enableEnterCardManually,
                 /* enableExpiryExtraction */ enableExpiryExtraction,
-                /* enableNameExtraction */ enableNameExtraction,
-                this::handleScanResult
+                /* enableNameExtraction */ enableNameExtraction
             );
         });
 

diff --git a/cardscan-ui/src/main/java/com/getbouncer/cardscan/ui/CardScanSheet.kt b/cardscan-ui/src/main/java/com/getbouncer/cardscan/ui/CardScanSheet.kt
@@ -40,10 +40,15 @@ sealed interface CardScanSheetResult : Parcelable {
 
 class CardScanSheet private constructor(private val apiKey: String) {
 
-    private var onFinished:
-        ((cardScanSheetResult: CardScanSheetResult) -> Unit)? = null
     private lateinit var launcher: ActivityResultLauncher<CardScanSheetParams>
 
+    /**
+     * Callback to notify when scanning finishes and a result is available.
+     */
+    fun interface CardScanResultCallback {
+        fun onCardScanSheetResult(cardScanSheetResult: CardScanSheetResult)
+    }
+
     companion object {
         /**
          * Create a [CardScanSheet] instance with [ComponentActivity].
@@ -57,22 +62,35 @@ class CardScanSheet private constructor(private val apiKey: String) {
         fun create(
             from: ComponentActivity,
             apiKey: String,
+            cardScanResultCallback: CardScanResultCallback,
             registry: ActivityResultRegistry = from.activityResultRegistry,
         ) = CardScanSheet(apiKey).apply {
-            launcher = from.registerForActivityResult(activityResultContract, registry, ::onResult)
+            launcher = from.registerForActivityResult(
+                activityResultContract,
+                registry,
+                cardScanResultCallback::onCardScanSheetResult,
+            )
         }
 
         @JvmStatic
         @JvmOverloads
         fun create(
             from: Fragment,
             apiKey: String,
+            cardScanResultCallback: CardScanResultCallback,
             registry: ActivityResultRegistry? = null,
         ) = CardScanSheet(apiKey).apply {
             launcher = if (registry != null) {
-                from.registerForActivityResult(activityResultContract, registry, ::onResult)
+                from.registerForActivityResult(
+                    activityResultContract,
+                    registry,
+                    cardScanResultCallback::onCardScanSheetResult,
+                )
             } else {
-                from.registerForActivityResult(activityResultContract, ::onResult)
+                from.registerForActivityResult(
+                    activityResultContract,
+                    cardScanResultCallback::onCardScanSheetResult,
+                )
             }
         }
 
@@ -138,9 +156,7 @@ class CardScanSheet private constructor(private val apiKey: String) {
         enableEnterManually: Boolean,
         enableNameExtraction: Boolean,
         enableExpiryExtraction: Boolean,
-        onFinished: (cardScanSheetResult: CardScanSheetResult) -> Unit
     ) {
-        this.onFinished = onFinished
         launcher.launch(
             CardScanSheetParams(
                 apiKey = apiKey,
@@ -150,11 +166,4 @@ class CardScanSheet private constructor(private val apiKey: String) {
             )
         )
     }
-
-    /**
-     * When a result is available from the activity, call [onFinished] if it's available.
-     */
-    private fun onResult(cardScanSheetResult: CardScanSheetResult) {
-        onFinished?.let { it(cardScanSheetResult) }
-    }
 }