diff -r 000000000000 -r 89d6a7a84779 Symbian3/SDK/Source/GUID-6163197B-7983-5FB7-9B92-02E490A900FB.dita --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Symbian3/SDK/Source/GUID-6163197B-7983-5FB7-9B92-02E490A900FB.dita Thu Jan 21 18:18:20 2010 +0000 @@ -0,0 +1,45 @@ + + + + + +How to +construct a headerThis document describes how to create a header for a doubly linked +list. +

In order to construct a header, two important pieces of information are +needed:

+ +

To create a header for a doubly linked list of CMyClass elements, +defined as:

+class CMyClass : public CBase + { + ... + TDblQueLink iDlink; + ... + }; +

construct a TDblQue as follows:

+TDblQue<CMyClass> queHeader(_FOFF(CMyClass,iDlink)); +

The TDblQue class takes a class template parameter which +defines the type of object which is to form an element of the list. In this +example, objects of type CMyClass form the elements of the +list.

+

The _FOFF macro (i.e. the "field offset" macro) calculates +the offset of the component link object within the element. In this example, +the required value is the offset of the iDlink data member +from the start of CMyClass.

+ + +<image href="GUID-29E7942D-A00D-5771-9782-59260965C687_d0e189052_href.png" placement="inline"/> +</fig> +</conbody></concept> \ No newline at end of file