Databases
StackOverflow2013
Postsdbo
POvirtual function question
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POvirtual function question
    primarykey
    data
    text
    <pre><code>#include "stdafx.h" #include &lt;iostream&gt; #include &lt;vector&gt; #include &lt;string&gt; class Helper { public: Helper() { init(); } virtual void print() { int nSize = m_vItems.size(); std::cout &lt;&lt; "Size : " &lt;&lt; nSize &lt;&lt; std::endl; std::cout &lt;&lt; "Items: " &lt;&lt; std::endl; for(int i=0; i&lt;nSize; i++) { std::cout &lt;&lt; m_vItems[i] &lt;&lt; std::endl; } } protected: virtual void init() { m_vItems.push_back("A"); } std::vector&lt;std::string&gt; m_vItems; }; class ItemsHelper : public Helper { public: ItemsHelper() { } protected: virtual void init() { Helper::init(); m_vItems.push_back("B"); } }; int _tmain(int argc, _TCHAR* argv[]) { ItemsHelper h; h.print(); } </code></pre> <p>This output's that the size of the vector is 1. I expected the size to be 2 because in the ItemsHelper::init function I called the base class <code>Helper::init()</code> function, then I add a second item to the vector. The problem is, the ItemsHelper::init doesn't get called, the base class init function gets called instead.</p> <p>I want the ItemsHelper::init function to get called, and I can do that by calling the init function in the ItemsHelper ctor rather than in the base class. <strong>BUT, the question is</strong>, is there a better way to achieve that and still keep the call to the init() in the base class? Because what if I want to create a Helper object instead of a ItemsHelper, then the init function would never get called.</p> <p>btw, this is a simplified version of a issue I'm seeing in a much larger object, I just made these objects up for example.</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. UScchampion
    plurals
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload