added undo on add, cut and paste controls

now cutted controls can be paste more times

src/ctrls/notebook.cpp

@@ -104,7 +104,6 @@ namespace ctrls
 
 		pages.push_back(child);
 
-		//
 		tbb.push_back(child->properties.property("caption").as_string());
 		tbb.attach(tbb.length() - 1, *child->nanawdg);
 
@@ -114,6 +113,37 @@ namespace ctrls
 	}
 
 
+	bool notebook::insert(ctrl* child, ctrl* pos, bool after)
+	{
+		if(!child)
+			return false;
+
+		int i = 0;
+		for(auto p = pages.begin(); p < pages.end(); ++p, ++i)
+		{
+			if(*p == pos)
+			{
+				if(after)
+				{
+					++p;
+					++i;
+				}
+
+				pages.insert(p, child);
+
+				tbb.insert(i, child->properties.property("caption").as_string());
+				tbb.attach(i, *child->nanawdg);
+
+				plc["pages"].fasten(*child->nanawdg);
+				plc.collocate();
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+
 	bool notebook::remove(ctrl* child)
 	{
 		if(!child)

src/ctrls/notebook.h

@@ -26,6 +26,7 @@ namespace ctrls
 
 		// relationship management
 		bool append(ctrl* child) override;
+		bool insert(ctrl* child, ctrl* pos, bool after) override;
 		bool remove(ctrl* child) override;
 		//
 		bool moveup(ctrl* child) override;