qtart android: make sure callbacks are rooted so they don't get GCed randomly

1 files changed, 24 insertions, 11 deletions

diff --git a/QuickJS-android/qtart/src/main/java/net/taler/qtart/TalerWalletCore.kt b/QuickJS-android/qtart/src/main/java/net/taler/qtart/TalerWalletCore.kt
index 6e0c605..b62014e 100644
--- a/QuickJS-android/qtart/src/main/java/net/taler/qtart/TalerWalletCore.kt
+++ b/QuickJS-android/qtart/src/main/java/net/taler/qtart/TalerWalletCore.kt
@@ -38,23 +38,28 @@ import com.sun.jna.Native
 import com.sun.jna.Pointer
 
 class TalerWalletCore {
-    private interface TalerNative: Library {
+    private interface TalerNative : Library {
         companion object {
             val INSTANCE: TalerNative by lazy {
                 Native.load("talerwalletcore", TalerNative::class.java)
             }
         }
 
-        interface TALER_WALLET_MessageHandlerFn: Callback {
+        interface TALER_WALLET_MessageHandlerFn : Callback {
             fun invoke(handler_p: Pointer, message: String)
         }
 
-        interface TALER_LogFn: Callback {
+        interface TALER_LogFn : Callback {
             fun invoke(cls: Pointer, stream: Int, msg: String)
         }
 
         fun TALER_WALLET_create(): Pointer
-        fun TALER_WALLET_set_message_handler(twi: Pointer, handler_f: TALER_WALLET_MessageHandlerFn, handler_p: Pointer)
+        fun TALER_WALLET_set_message_handler(
+            twi: Pointer,
+            handler_f: TALER_WALLET_MessageHandlerFn,
+            handler_p: Pointer
+        )
+
         fun TALER_WALLET_send_request(twi: Pointer, request: String): Int
         fun TALER_WALLET_run(twi: Pointer): Int
         fun TALER_WALLET_join(twi: Pointer)
@@ -63,21 +68,29 @@ class TalerWalletCore {
 
     private val walletInstance: Pointer = TalerNative.INSTANCE.TALER_WALLET_create()
 
+    private var currentMessageHandler: TalerNative.TALER_WALLET_MessageHandlerFn? = null
+    private var currentLogHandler: TalerNative.TALER_LogFn? = null
+
     fun setMessageHandler(handler: (msg: String) -> Unit) {
+        this.currentMessageHandler = object : TalerNative.TALER_WALLET_MessageHandlerFn {
+            override fun invoke(handler_p: Pointer, message: String) {
+                handler(message)
+            }
+        }
         TalerNative.INSTANCE.TALER_WALLET_set_message_handler(
-            walletInstance, object : TalerNative.TALER_WALLET_MessageHandlerFn {
-                override fun invoke(handler_p: Pointer, message: String) {
-                    handler(message)
-                }
-            }, walletInstance)
+            walletInstance,
+            this.currentMessageHandler!!,
+            walletInstance
+        )
     }
 
     fun setStdoutHandler(handler: (msg: String) -> Unit) {
-        TalerNative.INSTANCE.TALER_start_redirect_std(object : TalerNative.TALER_LogFn {
+        this.currentLogHandler = object : TalerNative.TALER_LogFn {
             override fun invoke(cls: Pointer, stream: Int, msg: String) {
                 handler(msg)
             }
-        }, walletInstance)
+        }
+        TalerNative.INSTANCE.TALER_start_redirect_std(this.currentLogHandler!!, walletInstance)
     }
 
     fun sendRequest(request: String) {