CHOP-763: Add LLView::TemporaryDrilldownFunc to support UI injection.

Instead of unconditionally calling LLView::pointInView(),
LLView::visibleAndContains() now consults a class-static boost::function
called sDrilldown -- which is initialized to LLView::pointInView().
Introduce LLView::TemporaryDrilldownFunc, instantiated with a callable whose
signature is compatible with LLView::pointInView(). This replaces sDrilldown,
but only for the life of the TemporaryDrilldownFunc object.
Introduce llview::TargetEvent, an object intended to serve as a
TemporaryDrilldownFunc callable. Construct it with a desired target LLView*
and pass it to TemporaryDrilldownFunc. When called with each candidate child
LLView*, instead of selecting the one containing the particular (x, y) point,
it selects the one that will lead to the ultimate desired target LLView*.
Add optional 'recur' param to LLView::childFromPoint(); default is current
one-level behavior. But when you pass recur=true, it should return the
frontmost visible leaf LLView containing the passed (x, y) point.

1 files changed, 30 insertions, 1 deletions

diff --git a/indra/llui/llview.h b/indra/llui/llview.h
index daea46d330..67634938fb 100644
--- a/indra/llui/llview.h
+++ b/indra/llui/llview.h
@@ -50,6 +50,7 @@
 #include "llfocusmgr.h"
 
 #include <list>
+#include <boost/function.hpp>
 
 class LLSD;
 
@@ -437,7 +438,7 @@ public:
 	/*virtual*/ void	screenPointToLocal(S32 screen_x, S32 screen_y, S32* local_x, S32* local_y) const;
 	/*virtual*/ void	localPointToScreen(S32 local_x, S32 local_y, S32* screen_x, S32* screen_y) const;
 
-	virtual		LLView*	childFromPoint(S32 x, S32 y);
+	virtual		LLView*	childFromPoint(S32 x, S32 y, bool recur=false);
 
 	// view-specific handlers 
 	virtual void	onMouseEnter(S32 x, S32 y, MASK mask);
@@ -599,7 +600,35 @@ private:
 
 	LLView& getDefaultWidgetContainer() const;
 
+	// This allows special mouse-event targeting logic for testing.
+	typedef boost::function<bool(const LLView*, S32 x, S32 y)> DrilldownFunc;
+	static DrilldownFunc sDrilldown;
+
 public:
+	// This is the only public accessor to alter sDrilldown. This is not
+	// an accident. The intended usage pattern is like:
+	// {
+	//     LLView::TemporaryDrilldownFunc scoped_func(myfunctor);
+	//     // ... test with myfunctor ...
+	// } // exiting block restores original LLView::sDrilldown
+	class TemporaryDrilldownFunc
+	{
+	public:
+		TemporaryDrilldownFunc(const DrilldownFunc& func):
+			mOldDrilldown(sDrilldown)
+		{
+			sDrilldown = func;
+		}
+
+		~TemporaryDrilldownFunc()
+		{
+			sDrilldown = mOldDrilldown;
+		}
+
+	private:
+		DrilldownFunc mOldDrilldown;
+	};
+
 	// Depth in view hierarchy during rendering
 	static S32	sDepth;