You can only select one of the following:
The data explorer shows the data according to the given type. This is the normal mode.
Only the type information is displayed. In C++, a list of all member functions of the type is displayed. Left clicking a member function causes the source pane to display that function. Warning: Inlined functions are not shown in the list.
Using the same "my_tree" example above, we choose Format > Type:
The address of the viewed object displays memory in an infinitely scrollable fashion, limited only by the memory of the machine. In this mode, the scroll thumb is fixed in the center of the scrollbar. You can click above or below the fixed scroll thumb, or on the scroll arrows, to scroll the windows.
See also "Data explorers with an infinite view".