1 files changed, 25 insertions, 0 deletions

diff --git a/src/api/burn/WixToolset.Mba.Core/BootstrapperApplication.cs b/src/api/burn/WixToolset.Mba.Core/BootstrapperApplication.cs
index fd36cf26..8a2e0e93 100644
--- a/src/api/burn/WixToolset.Mba.Core/BootstrapperApplication.cs
+++ b/src/api/burn/WixToolset.Mba.Core/BootstrapperApplication.cs
@@ -209,6 +209,9 @@ namespace WixToolset.Mba.Core
         public event EventHandler<ApplyCompleteEventArgs> ApplyComplete;
 
         /// <inheritdoc/>
+        public event EventHandler<ApplyDowngradeEventArgs> ApplyDowngrade;
+
+        /// <inheritdoc/>
         public event EventHandler<ExecuteProgressEventArgs> ExecuteProgress;
 
         /// <inheritdoc/>
@@ -1056,6 +1059,19 @@ namespace WixToolset.Mba.Core
         }
 
         /// <summary>
+        /// Called by the engine, raises the <see cref="ApplyDowngrade"/> event.
+        /// </summary>
+        /// <param name="args">Additional arguments for this event.</param>
+        protected virtual void OnApplyDowngrade(ApplyDowngradeEventArgs args)
+        {
+            EventHandler<ApplyDowngradeEventArgs> handler = this.ApplyDowngrade;
+            if (null != handler)
+            {
+                handler(this, args);
+            }
+        }
+
+        /// <summary>
         /// Called by the engine, raises the <see cref="ExecuteProgress"/> event.
         /// </summary>
         /// <param name="args">Additional arguments for this event.</param>
@@ -1907,6 +1923,15 @@ namespace WixToolset.Mba.Core
             return args.HResult;
         }
 
+        int IBootstrapperApplication.OnApplyDowngrade(int hrRecommendation, ref int hrStatus)
+        {
+            ApplyDowngradeEventArgs args = new ApplyDowngradeEventArgs(hrRecommendation, hrStatus);
+            this.OnApplyDowngrade(args);
+
+            hrStatus = args.Status;
+            return args.HResult;
+        }
+
         int IBootstrapperApplication.OnLaunchApprovedExeBegin(ref bool fCancel)
         {
             LaunchApprovedExeBeginEventArgs args = new LaunchApprovedExeBeginEventArgs(fCancel);