Second Life viewer sources 1.17.0.12

1 files changed, 91 insertions, 0 deletions

diff --git a/linden/indra/llui/llui.h b/linden/indra/llui/llui.h
index 6b8a86a..3085bd9 100644
--- a/linden/indra/llui/llui.h
+++ b/linden/indra/llui/llui.h
@@ -275,4 +275,95 @@ typedef enum e_widget_type
         WIDGET_TYPE_COUNT
 } EWidgetType;
 
+// Manages generation of UI elements by LLSD, such that there is
+// only one instance per uniquely identified LLSD parameter
+// Class T is the instance type being managed, and INSTANCE_ADDAPTOR
+// wraps an instance of the class with handlers for show/hide semantics, etc.
+template <class T, class INSTANCE_ADAPTOR = T>
+class LLUIInstanceMgr
+{
+public:
+        LLUIInstanceMgr()
+        {
+        }
+
+        virtual ~LLUIInstanceMgr() 
+        { 
+        }
+
+        // default show and hide methods
+        static T* showInstance(const LLSD& seed) 
+        { 
+                T* instance = INSTANCE_ADAPTOR::getInstance(seed); 
+                INSTANCE_ADAPTOR::show(instance);
+                return instance;
+        }
+
+        static void hideInstance(const LLSD& seed) 
+        { 
+                T* instance = INSTANCE_ADAPTOR::getInstance(seed); 
+                INSTANCE_ADAPTOR::hide(instance);
+        }
+
+        static void toggleInstance(const LLSD& seed)
+        {
+                if (!INSTANCE_ADAPTOR::instanceVisible(seed))
+                {
+                        INSTANCE_ADAPTOR::showInstance(seed);
+                }
+                else
+                {
+                        INSTANCE_ADAPTOR::hideInstance(seed);
+                }
+        }
+
+        static BOOL instanceVisible(const LLSD& seed)
+        {
+                T* instance = INSTANCE_ADAPTOR::findInstance(seed);
+                return instance != NULL && INSTANCE_ADAPTOR::visible(instance);
+        }
+
+        static T* getInstance(const LLSD& seed) 
+        {
+                T* instance = INSTANCE_ADAPTOR::findInstance(seed);
+                if (instance == NULL)
+                {
+                        instance = INSTANCE_ADAPTOR::createInstance(seed);
+                }
+                return instance;
+        }
+};
+
+// Creates a UI singleton by ignoring the identifying parameter
+// and always generating the same instance via the LLUIInstanceMgr interface.
+// Note that since UI elements can be destroyed by their hierarchy, this singleton
+// pattern uses a static pointer to an instance that will be re-created as needed.
+template <class T, class INSTANCE_ADAPTOR = T>
+class LLUISingleton: public LLUIInstanceMgr<T, INSTANCE_ADAPTOR>
+{
+public:
+        // default constructor assumes T is derived from LLUISingleton (a true singleton)
+        LLUISingleton() : LLUIInstanceMgr<T, INSTANCE_ADAPTOR>() { sInstance = (T*)this; }
+        ~LLUISingleton() { sInstance = NULL; }
+
+        static T* findInstance(const LLSD& seed)
+        {
+                return sInstance;
+        }
+
+        static T* createInstance(const LLSD& seed)
+        {
+                if (sInstance == NULL)
+                {
+                        sInstance = new T(seed);
+                }
+                return sInstance;
+        }
+
+protected:
+        static T*       sInstance;
+};
+
+template <class T, class U> T* LLUISingleton<T,U>::sInstance = NULL;
+
 #endif