RefBase subclasses can now decide how they want to be destroyed.

This adds a destroy() virtual on RefBase which
sublasses can implement. destroy() is called
in lieu of the destructor whenthe last strong
ref goes away.

2 files changed, 13 insertions, 3 deletions

diff --git a/include/utils/RefBase.h b/include/utils/RefBase.h
index f355087713..412622596c 100644
--- a/include/utils/RefBase.h
+++ b/include/utils/RefBase.h
@@ -51,7 +51,6 @@ inline bool operator _op_ (const U* o) const {                  \
 }
 
 // ---------------------------------------------------------------------------
-
 class ReferenceMover;
 class ReferenceConverterBase {
 public:
@@ -120,7 +119,14 @@ public:
 protected:
                             RefBase();
     virtual                 ~RefBase();
-    
+
+    // called when the last reference goes away. this is responsible for
+    // calling the destructor. The default implementation just does
+    // "delete this;".
+    // Make sure to never acquire a strong reference from this function. The
+    // same restrictions than for destructors apply.
+    virtual void            destroy() const;
+
     //! Flags for extendObjectLifetime()
     enum {
         OBJECT_LIFETIME_WEAK    = 0x0001,
diff --git a/libs/utils/RefBase.cpp b/libs/utils/RefBase.cpp
index 2034486aac..9f55a71579 100644
--- a/libs/utils/RefBase.cpp
+++ b/libs/utils/RefBase.cpp
@@ -345,6 +345,10 @@ void RefBase::incStrong(const void* id) const
     const_cast<RefBase*>(this)->onFirstRef();
 }
 
+void RefBase::destroy() const {
+    delete this;
+}
+
 void RefBase::decStrong(const void* id) const
 {
     weakref_impl* const refs = mRefs;
@@ -357,7 +361,7 @@ void RefBase::decStrong(const void* id) const
     if (c == 1) {
         const_cast<RefBase*>(this)->onLastStrongRef(id);
         if ((refs->mFlags&OBJECT_LIFETIME_WEAK) != OBJECT_LIFETIME_WEAK) {
-            delete this;
+            destroy();
         }
     }
     refs->decWeak(id);