...

app/src/main/java/com/base/pdfviewerscannerwhite/ui/document/pdf/PdfMergeActivity.kt

@@ -109,7 +109,7 @@ class PdfMergeActivity : BaseActivity<ActivityPdfMergeBinding>() {
                 }
             }
 
-        }else{
+        } else {
             callBack.invoke()
         }
     }
@@ -121,7 +121,7 @@ class PdfMergeActivity : BaseActivity<ActivityPdfMergeBinding>() {
         adapter = PdfMergeAdapter(itemTouchHelper, callBack)
         adapter.removeAction = {
             mergePdfList.remove(it)
-            binding.tvBtnNext.isEnabled = mergePdfList.isNotEmpty()
+            binding.tvBtnNext.isEnabled = mergePdfList.size >= 2
         }
         binding.rv.adapter = adapter
 
@@ -142,6 +142,7 @@ class PdfMergeActivity : BaseActivity<ActivityPdfMergeBinding>() {
         }
 
         mergePdfList.let { adapter.submitList(it) }
+        binding.tvBtnNext.isEnabled = mergePdfList.size >= 2
     }
 
     companion object {

app/src/main/res/layout/activity_pdf_merge.xml

@@ -81,7 +81,7 @@
         android:layout_height="48dp"
         android:layout_marginBottom="24dp"
         android:background="@drawable/bg_selector_btn"
-        android:enabled="true"
+        android:enabled="false"
         android:gravity="center"
         android:text="Merge"
         android:textColor="@color/white"