Fix "bounce" when sending a message on Android 16

app/src/main/java/org/thoughtcrime/securesms/conversation/v2/ConversationActivityV2.kt

@@ -474,7 +474,9 @@ class ConversationActivityV2 : ScreenLockActionBarActivity(), InputBarDelegate,
     }
 
     private val isScrolledToBottom: Boolean
-        get() = binding.conversationRecyclerView.isNearBottom
+        get() = with(binding.conversationRecyclerView){
+            !canScrollVertically(1) || isNearBottom
+        }
 
     // When the user clicks on the original message in a reply then we scroll to and highlight that original
     // message. To do this we keep track of the replied-to message's location in the recycler view.
@@ -2120,9 +2122,6 @@ class ConversationActivityV2 : ScreenLockActionBarActivity(), InputBarDelegate,
         if (sentMessageInfo != null) {
             messageToScrollAuthor.set(sentMessageInfo.first)
             messageToScrollTimestamp.set(sentMessageInfo.second)
-            binding.conversationRecyclerView.postDelayed({
-                binding.conversationRecyclerView.handleScrollToBottom()
-            }, 500L)
         }
     }
 

app/src/main/java/org/thoughtcrime/securesms/util/GeneralUtilities.kt

@@ -1,6 +1,7 @@
 package org.thoughtcrime.securesms.util
 
 import android.content.res.Resources
+import android.util.Log
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import kotlin.math.roundToInt
@@ -23,13 +24,23 @@ fun toDp(px: Float, resources: Resources): Float {
     return (px / scale)
 }
 
-/**
- * Returns true if the recyclerview is scrolled within 50dp of the bottom
- */
 val RecyclerView.isNearBottom: Boolean
-    get() = computeVerticalScrollOffset().coerceAtLeast(0) +
-            computeVerticalScrollExtent() +
-            toPx(50, resources) >= computeVerticalScrollRange()
+    get() {
+        val offset = computeVerticalScrollOffset().coerceAtLeast(0)
+        val extent = computeVerticalScrollExtent()
+        val range = computeVerticalScrollRange()
+        val thresholdPx = toPx(50, resources)
+
+        // If there's no scrollable area, don't treat it as "near bottom"
+        if (range <= extent) {
+            return false
+        }
+
+        val remaining = range - (offset + extent) // distance from bottom in px
+
+        // true only when remaining distance to bottom <= 50dp
+        return remaining <= thresholdPx
+    }
 
 val RecyclerView.isFullyScrolled: Boolean
     get() {