Hi all,
I have noticed that I over and over again write member functions which
iterate over vectors and other containers.
Is there a standard way of doing this, like assigning a template
function to a range of container iterators?
<example code>
//show the eventui vector
int y = 20, v_interval = 20;
std::vector<QxE ventUI*>::itera tor it = m_widget_vector .begin();
while( it != m_widget_vector .end() ){
(*it)->show();
y+=v_interval;
it++;
}
</example code>
In the above example I iterate and execute show() for each vector
element. I'd like to set a template function for the iteration and for
each element execute it, how to do that?
any help and advice highly appreciated.
Thank you
/B 1 3910
Bob Smith wrote: Hi all, I have noticed that I over and over again write member functions which iterate over vectors and other containers. Is there a standard way of doing this, like assigning a template function to a range of container iterators?
<example code>
//show the eventui vector int y = 20, v_interval = 20; std::vector<QxE ventUI*>::itera tor it = m_widget_vector .begin(); while( it != m_widget_vector .end() ){ (*it)->show(); y+=v_interval; it++; } </example code>
In the above example I iterate and execute show() for each vector element. I'd like to set a template function for the iteration and for each element execute it, how to do that?
You can use the 'for_each' generic algorithm:
template<class InputIterator, class Function>
Function for_each(Inpute rIterator first, InputIterator last, Function func);
a partial solution based on your example:
void showQxEventUI(Q xEventUI * element) {
element->show();
}
void (*pfi=)(int)=sh owQxEventUI;
for_each(m_widg et_vector.begin (),m_widget_vec tor.end(),pfi);
If you need to update the elements, the 'transform' generic algorithm
can be used.
In both cases, a problem remains to udate variables outside the scope of
the function or object in the list. For example, your y and v_interval
variables in your example. any help and advice highly appreciated. Thank you /B This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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