diff --git a/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityEventWrapper.kt b/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityEventWrapper.kt
index f72a42d44..d08e5d266 100644
--- a/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityEventWrapper.kt
+++ b/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityEventWrapper.kt
@@ -27,12 +27,12 @@ class AccessibilityEventWrapper(event: AccessibilityEvent) {
     }
 
     private fun getIndexInParent(node: AccessibilityNodeInfo): Int {
-        var index = 0
-        val parent = node.parent ?: return 0
-        while (parent.getChild(index) != node) {
-            index++
+        return try {
+            val parent = node.parent ?: return -1
+            findIndexInParent(parent.childCount, parent::getChild, node)
+        } catch (_: RuntimeException) {
+            -1
         }
-        return index
     }
 }
 
diff --git a/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityNodeIndex.kt b/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityNodeIndex.kt
new file mode 100644
index 000000000..e39e6d363
--- /dev/null
+++ b/app/src/main/java/org/autojs/autojs/core/automator/AccessibilityNodeIndex.kt
@@ -0,0 +1,18 @@
+package org.autojs.autojs.core.automator
+
+internal fun <T> findIndexInParent(
+    childCount: Int,
+    childAt: (Int) -> T?,
+    target: T,
+): Int {
+    return try {
+        for (index in 0 until childCount) {
+            if (childAt(index) == target) {
+                return index
+            }
+        }
+        -1
+    } catch (_: RuntimeException) {
+        -1
+    }
+}
diff --git a/app/src/test/java/org/autojs/autojs/core/automator/AccessibilityNodeIndexTest.kt b/app/src/test/java/org/autojs/autojs/core/automator/AccessibilityNodeIndexTest.kt
new file mode 100644
index 000000000..41e001f7a
--- /dev/null
+++ b/app/src/test/java/org/autojs/autojs/core/automator/AccessibilityNodeIndexTest.kt
@@ -0,0 +1,32 @@
+package org.autojs.autojs.core.automator
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class AccessibilityNodeIndexTest {
+
+    @Test
+    fun `returns sentinel without reading past child count when target disappears`() {
+        val children = listOf("remaining-child")
+
+        val index = findIndexInParent(children.size, children::get, "detached-child")
+
+        assertEquals(-1, index)
+    }
+
+    @Test
+    fun `returns sentinel when child access fails`() {
+        val index = findIndexInParent(1, { throw IllegalStateException("stale node") }, "target")
+
+        assertEquals(-1, index)
+    }
+
+    @Test
+    fun `returns target index when child is present`() {
+        val children = listOf("first", "target", "last")
+
+        val index = findIndexInParent(children.size, children::get, "target")
+
+        assertEquals(1, index)
+    }
+}