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  • Sorting and indexing into a list in a Django template?

    - by slypete
    How can you perform complex sorting on an object before passing it to the template? For example, here is my view: @login_required def overview(request): physicians = PhysicianGroup.objects.get(pk=physician_group).physicians for physician in physicians.all(): physician.service_patients.order_by('bed__room__unit', 'bed__room__order', 'bed__order') return render_to_response('hospitalists/overview.html', RequestContext(request, {'physicians': physicians,})) The physicians object is not ordered correctly in the template. Why not? Additionally, how do you index into a list inside the template? For example, (this doesn't work): {% for note_type in note_types %} <div><h3>{{ note_type }}</h3> {% for notes in note_sets.index(parent.forloop.counter0) %} #only want to display the notes of this note_type! {% for note in notes %} <p>{{ note }}</p> {% endfor %} {% endfor %} </div> {% endfor %}

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  • How can I display multiple django modelformset forms in a grouped fieldsets?

    - by JT
    I have a problem with needing to provide multiple model backed forms on the same page. I understand how to do this with single forms, i.e. just create both the forms call them something different then use the appropriate names in the template. Now how exactly do you expand that solution to work with modelformsets? The wrinkle, of course, is that each 'form' must be rendered together in the appropriate fieldset. For example I want my template to produce something like this: <fieldset> <label for="id_base-0-desc">Home Base Description:</label> <input id="id_base-0-desc" type="text" name="base-0-desc" maxlength="100" /> <label for="id_likes-0-icecream">Want ice cream?</label> <input type="checkbox" name="likes-0-icecream" id="id_likes-0-icecream" /> </fieldset> <fieldset> <label for="id_base-1-desc">Home Base Description:</label> <input id="id_base-1-desc" type="text" name="base-1-desc" maxlength="100" /> <label for="id_likes-1-icecream">Want ice cream?</label> <input type="checkbox" name="likes-1-icecream" id="id_likes-1-icecream" /> </fieldset> I am using a loop like this to process the results (after form validation) base_models = base_formset.save(commit=False) like_models = like_formset.save(commit=False) for base_model, likes_model in map(None, base_models, likes_models): which works as I'd expect (I'm using map because the # of forms can be different). The problem is that I can't figure out a way to do the same thing with the templating engine. The system does work if I layout all the base models together then all the likes models after wards, but it doesn't meet the layout requirements. EDIT: Updated the problem statement to be more clear about what exactly I'm processing (I'm processing models not forms in the for loop)

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  • Get list of Unique many-to-many records from a queryset

    - by rsp
    My models: class Order(models.Model): ordered_by = models.ForeignKey(User) reasons = models.ManyToManyField(Reason) class Reason(models.Model): description = models.CharField() Basically a user creates an order and gives reasons for that order. ie, john has two orders (one for pencils because he is out AND because he doesn't like his current stock. a second order for pens because he is out). I want to print a list out of all reasons a user has placed his orders. So under john, it should print "he is out", "he doesn't like his current stock"; those two lines only. If I simply select all of john's orders, iterate through them and print out their "reasons" it'll print "he is out", "he doesn't like his current stock" and then "he is out" again. I don't want these duplicate values. How do I select a list of his reasons for ALL his orders so that the list has all unique rows?

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  • Django snippet with logic

    - by etam
    Hi, is there a way to create a Django snippet that has logic? I think about something like contact template tag: {% contact_form %} with template: <form action="send_contact_form" method="POST">...</form> with logic: def send_contact_form(): ... I want to be able to use it anywhere in my projects. It should work only by specifying 1 template tag... Do you know what I mean? Is it possible? Thanks in advance, Etam.

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  • boost smart pointers and BOOST_NO_MEMBER_TEMPLATES

    - by Johann Gerell
    After some struggling I managed to get boost smart pointers to build for Windows CE/Mobile at warning level 4. I found the least-resistance-way to get rid of compile errors and warnings to be #define BOOST_NO_MEMBER_TEMPLATES What does it actually mean? Did I sell my soul to the devil? Will all hell break loose when I actually use the types?

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  • Smart pointers and polymorphism

    - by qwerty
    hello. I implemented reference counting pointers (called SP in the example) and im having problems with polymorphism which i think i shouldn't have. In the following code: SP<BaseClass> foo() { // Some logic... SP<DerivedClass> retPtr = new DerivedClass(); return retPtr; } DerivedClass inherits from BaseClass. With normal pointers this should have worked, but with the smart pointers it says "cannot convert from 'SP<T>' to 'const SP<T>&" and i think it refers to the copy constructor of the smart pointer. How to i allow this kind of polymorphism with reference counting pointer? I'd appreciate code samples cause obviously im doing something wrong here if im having this problem. Thanks! :) [p.s., plz don't tell me to use standart liberary with smart pointers cuz that's impossible at this moment.]

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  • C++ "if then else" template substitution

    - by duli
    I would like to declare a template as follows: template <typename T> { if objects of class T have method foo(), then const int k=1 else if class has a static const int L then const int k=L else const int k=0; } How can I do this? In general, I would like a mechanism for setting static consts based on properties of T (or typedef defined inside T).

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  • Django Template tag, generating template block tag

    - by Issy
    Hi Guys, Currently a bit stuck, wondering if anyone can assist. I am using django-adminfiles. Which is a near little application. I want to use it to insert images into posts/articles/pages for a site i am building. How django-adminfiles works is it inserts a placeholder i.e <<< ImageFile and this gets rendered using a django template. It also has the feature of inserting custom options i.e (Insert Medium Image) , i figured i would used this to automatically resize images and include it in the post (similar to how WP does it). Django-adminfiles makes use of sorl.thumbnail app to generate thumbnails. So i have tried testing generating thumbnails: The current template that is used to render the inserted image is: {% spaceless %} <img src="{{ upload.upload.url }}" width="{{ upload.width }}" height="{{ upload.height }}" class="{{ options.class }}" class="{{ options.size }}" alt="{% if options.alt %}{{ options.alt }}{% else %}{{ upload.title }}{% endif %}" /> {% endspaceless %} I tried modifying this to: {% load thumbnail %} {% spaceless %} <img src="{% thumbnail upload.upload.url 200x50 %}" width="{{ upload.width }}" height="{{ upload.height }}" class="{{ options.class }}" class="{{ options.size }}" alt="{% if options.alt %}{{ options.alt }}{% else %}{{ upload.title }}{% endif %}" /> {% endspaceless %} I get the error: Exception Value: Caught an exception while rendering: Source file: '/media/uploads/DSC_0014.jpg' does not exist. I figured the thumbnail needs the absolute path so tried putting that in the template, and that works. i.e this works: {% thumbnail '/Users/me/media/uploads/DSC_0014.jpg' 200x50 %} So basically i need to generate the absolute path to the file give the relative path (to web root). You could do this by passing the MEDIA_ROOT setting to the template, but the reason i want to do a template tag is to programmatically set the image size.

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  • Using a type parameter and a pointer to the same type parameter in a function template

    - by Darel
    Hello, I've written a template function to determine the median of any vector or array of any type that can be sorted with sort. The function and a small test program are below: #include <algorithm> #include <vector> #include <iostream> using namespace::std; template <class T, class X> void median(T vec, size_t size, X& ret) { sort(vec, vec + size); size_t mid = size/2; ret = size % 2 == 0 ? (vec[mid] + vec[mid-1]) / 2 : vec[mid]; } int main() { vector<double> v; v.push_back(2); v.push_back(8); v.push_back(7); v.push_back(4); v.push_back(9); double a[5] = {2, 8, 7, 4, 9}; double r; median(v.begin(), v.size(), r); cout << r << endl; median(a, 5, r); cout << r << endl; return 0; } As you can see, the median function takes a pointer as an argument, T vec. Also in the argument list is a reference variable X ret, which is modified by the function to store the computed median value. However I don't find this a very elegant solution. T vec will always be a pointer to the same type as X ret. My initial attempts to write median had a header like this: template<class T> T median(T *vec, size_t size) { sort(vec, vec + size); size_t mid = size/2; return size % 2 == 0 ? (vec[mid] + vec[mid-1]) / 2 : vec[mid]; } I also tried: template<class T, class X> X median(T vec, size_t size) { sort(vec, vec + size); size_t mid = size/2; return size % 2 == 0 ? (vec[mid] + vec[mid-1]) / 2 : vec[mid]; } I couldn't get either of these to work. My question is, can anyone show me a working implementation of either of my alternatives? Thanks for looking!

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  • Django - markup parser in template or view?

    - by Amit Ron
    I am building a website where my pages are written in MediaWiki Markup, for which I have a working parser function in Python. Where exactly do I parse my markup: in the view's code, or in the template? My first guess would be something like: return render_to_response( 'blog/post.html', {'post': post, 'content': parseMyMarkup(post.content) }) Is this the usual convention, or should I do something different?

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  • ASP.NET MVC: Accessing ModelMetadata for items in a collection

    - by DanM
    I'm trying to write an auto-scaffolder for Index views. I'd like to be able to pass in a collection of models or view-models (e.g., IEnumerable<MyViewModel>) and get back an HTML table that uses the DisplayName attribute for the headings (th elements) and Html.Display(propertyName) for the cells (td elements). Each row should correspond to one item in the collection. When I'm only displaying a single record, as in a Details view, I use ViewData.ModelMetadata.Properties to obtain the list of properties for a given model. But what happens when the model I pass to the view is a collection of model or view-model objects and not a model or view-model itself? How do I obtain the ModelMetadata for a particular item in a collection?

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  • initializer_list and move semantics

    - by FredOverflow
    Am I allowed to move elements out of a std::initializer_list<T>? #include <initializer_list> #include <utility> template<typename T> void foo(std::initializer_list<T> list) { for (auto it = list.begin(); it != list.end(); ++it) { bar(std::move(*it)); // kosher? } } Since std::intializer_list<T> requires special compiler attention and does not have value semantics like normal containers of the C++ standard library, I'd rather be safe than sorry and ask.

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  • Higher order function « filter » in C++

    - by Red Hyena
    Hi all. I wanted to write a higher order function filter with C++. The code I have come up with so far is as follows: #include <iostream> #include <string> #include <functional> #include <algorithm> #include <vector> #include <list> #include <iterator> using namespace std; bool isOdd(int const i) { return i % 2 != 0; } template < template <class, class> class Container, class Predicate, class Allocator, class A > Container<A, Allocator> filter(Container<A, Allocator> const & container, Predicate const & pred) { Container<A, Allocator> filtered(container); container.erase(remove_if(filtered.begin(), filtered.end(), pred), filtered.end()); return filtered; } int main() { int const a[] = {23, 12, 78, 21, 97, 64}; vector<int const> const v(a, a + 6); vector<int const> const filtered = filter(v, isOdd); copy(filtered.begin(), filtered.end(), ostream_iterator<int const>(cout, " ")); } However on compiling this code, I get the following error messages that I am unable to understand and hence get rid of: /usr/include/c++/4.3/ext/new_allocator.h: In instantiation of ‘__gnu_cxx::new_allocator<const int>’: /usr/include/c++/4.3/bits/allocator.h:84: instantiated from ‘std::allocator<const int>’ /usr/include/c++/4.3/bits/stl_vector.h:75: instantiated from ‘std::_Vector_base<const int, std::allocator<const int> >’ /usr/include/c++/4.3/bits/stl_vector.h:176: instantiated from ‘std::vector<const int, std::allocator<const int> >’ Filter.cpp:29: instantiated from here /usr/include/c++/4.3/ext/new_allocator.h:82: error: ‘const _Tp* __gnu_cxx::new_allocator<_Tp>::address(const _Tp&) const [with _Tp = const int]’ cannot be overloaded /usr/include/c++/4.3/ext/new_allocator.h:79: error: with ‘_Tp* __gnu_cxx::new_allocator<_Tp>::address(_Tp&) const [with _Tp = const int]’ Filter.cpp: In function ‘Container<A, Allocator> filter(const Container<A, Allocator>&, const Predicate&) [with Container = std::vector, Predicate = bool ()(int), Allocator = std::allocator<const int>, A = const int]’: Filter.cpp:30: instantiated from here Filter.cpp:23: error: passing ‘const std::vector<const int, std::allocator<const int> >’ as ‘this’ argument of ‘__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> > std::vector<_Tp, _Alloc>::erase(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, __gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >) [with _Tp = const int, _Alloc = std::allocator<const int>]’ discards qualifiers /usr/include/c++/4.3/bits/stl_algo.h: In function ‘_FIter std::remove_if(_FIter, _FIter, _Predicate) [with _FIter = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >, _Predicate = bool (*)(int)]’: Filter.cpp:23: instantiated from ‘Container<A, Allocator> filter(const Container<A, Allocator>&, const Predicate&) [with Container = std::vector, Predicate = bool ()(int), Allocator = std::allocator<const int>, A = const int]’ Filter.cpp:30: instantiated from here /usr/include/c++/4.3/bits/stl_algo.h:821: error: assignment of read-only location ‘__result.__gnu_cxx::__normal_iterator<_Iterator, _Container>::operator* [with _Iterator = const int*, _Container = std::vector<const int, std::allocator<const int> >]()’ /usr/include/c++/4.3/ext/new_allocator.h: In member function ‘void __gnu_cxx::new_allocator<_Tp>::deallocate(_Tp*, size_t) [with _Tp = const int]’: /usr/include/c++/4.3/bits/stl_vector.h:150: instantiated from ‘void std::_Vector_base<_Tp, _Alloc>::_M_deallocate(_Tp*, size_t) [with _Tp = const int, _Alloc = std::allocator<const int>]’ /usr/include/c++/4.3/bits/stl_vector.h:136: instantiated from ‘std::_Vector_base<_Tp, _Alloc>::~_Vector_base() [with _Tp = const int, _Alloc = std::allocator<const int>]’ /usr/include/c++/4.3/bits/stl_vector.h:286: instantiated from ‘std::vector<_Tp, _Alloc>::vector(_InputIterator, _InputIterator, const _Alloc&) [with _InputIterator = const int*, _Tp = const int, _Alloc = std::allocator<const int>]’ Filter.cpp:29: instantiated from here /usr/include/c++/4.3/ext/new_allocator.h:98: error: invalid conversion from ‘const void*’ to ‘void*’ /usr/include/c++/4.3/ext/new_allocator.h:98: error: initializing argument 1 of ‘void operator delete(void*)’ /usr/include/c++/4.3/bits/stl_algobase.h: In function ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = false, _II = const int*, _OI = const int*]’: /usr/include/c++/4.3/bits/stl_algobase.h:435: instantiated from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = false, _II = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >, _OI = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >]’ /usr/include/c++/4.3/bits/stl_algobase.h:466: instantiated from ‘_OI std::copy(_II, _II, _OI) [with _II = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >, _OI = __gnu_cxx::__normal_iterator<const int*, std::vector<const int, std::allocator<const int> > >]’ /usr/include/c++/4.3/bits/vector.tcc:136: instantiated from ‘__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> > std::vector<_Tp, _Alloc>::erase(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, __gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >) [with _Tp = const int, _Alloc = std::allocator<const int>]’ Filter.cpp:23: instantiated from ‘Container<A, Allocator> filter(const Container<A, Allocator>&, const Predicate&) [with Container = std::vector, Predicate = bool ()(int), Allocator = std::allocator<const int>, A = const int]’ Filter.cpp:30: instantiated from here /usr/include/c++/4.3/bits/stl_algobase.h:396: error: no matching function for call to ‘std::__copy_move<false, true, std::random_access_iterator_tag>::__copy_m(const int*&, const int*&, const int*&)’ Please tell me what I am doing wrong here and what is the correct way to achieve the kind of higher order polymorphism I want. Thanks.

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  • Django Custom Template Tages: Inclusion Tags

    - by Harry
    Hello world! Im trieng to build my own template tags Im have no idea why I get the errors I get, im following the django doc's. this is my file structure of my app: pollquiz/ __init__.py show_pollquiz.html showpollquiz.py This is showpollquiz.py: from django import template from pollquiz.models import PollQuiz, Choice register = template.Library() @register.inclusion_tag('show_pollquiz.html') def show_poll(): poll = Choice.objects.all() return { 'poll' : poll } html file: <ul> {% for poll in poll <li>{{ poll.pollquiz }}</li> {% endfor </ul> in my base.html file im am including like this {% load showpollquiz %} and {% poll_quiz %} Bu then I get the the error: Exception Value: Caught an exception while rendering: show_pollquiz.html I have no idea why this happens. Any ideas? Please keep in mind Im still new to Django

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  • Django template call function

    - by cleg
    I'm passing to Django's template a function, which returns me some records. I want to call this function and iterate over it's result. {% for item in my_func(10) %} That doesn't work. I've tried to set fuction's return value to a variable and iterate over variable, but there seems to be no way to set variable in Django template. Is there any normal way to do it?

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  • Button template with image and text in wpf

    - by Archana R
    Hello, I want to create buttons with images and text inside. For example, i would use different images and text for buttons like 'Browse folders' and 'Import'. One of the options would be to use a template. I had a look at simliar question http://stackoverflow.com/questions/1933127/creating-an-imagetext-button-with-a-control-template But is there any way by which i can bind the source of image without using a dependency property or any other class? Thanks

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  • url template tag in django template

    - by user192048
    guys: I was trying to use the url template tag in django, but no lucky, I defined my urls.py like this urlpatterns = patterns('', url(r'^analyse/$', views.home, name="home"), url(r'^analyse/index.html', views.index, name="index"), url(r'^analyse/setup.html', views.setup, name="setup"), url(r'^analyse/show.html', views.show, name="show"), url(r'^analyse/generate.html', views.generate, name="generate"), I defined the url pattern in my view like this {% url 'show'%} then I got this error message Caught an exception while rendering: Reverse for ''show'' with arguments '()' and keyword arguments '{}' not found. Original Traceback (most recent call last): File "/Library/Python/2.5/site-packages/django/template/debug.py", line 71, in render_node result = node.render(context) File "/Library/Python/2.5/site-packages/django/template/defaulttags.py", line 155, in render nodelist.append(node.render(context)) File "/Library/Python/2.5/site-packages/django/template/defaulttags.py", line 382, in render raise e NoReverseMatch: Reverse for ''show'' with arguments '()' and keyword arguments '{}' not found. I am wondering why django failed to render? what is the right way to define it in the tempalte?

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  • How to have a policy class implement a virtual function?

    - by dehmann
    I'm trying to design a policy-based class, where a certain interface is implemented by the policy itself, so the class derives from the policy, which itself is a template (I got this kind of thinking from Alexandrescu's book): #include <iostream> #include <vector> class TestInterface { public: virtual void test() = 0; }; class TestImpl1 { public: void test() {std::cerr << "Impl1" << std::endl;} }; template<class TestPolicy> class Foo : public TestInterface, TestPolicy { }; Then, in the main() function, I call test() on (potentially) various different objects that all implement the same interface: int main() { std::vector<TestInterface*> foos; foos.push_back(new Foo<TestImpl1>()); foos[0]->test(); delete foos[0]; return 0; } It doesn't compile, though, because the following virtual functions are pure within ‘Foo<TestImpl1>’: virtual void TestInterface::test() I thought TestInterface::test() is implemented because we derive from TestImpl1?

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  • Codeigniter + Dwoo

    - by RedTruck
    I got problem when implementing my CMS using Codeigniter 1.7.2 and Dwoo. I use Phil Sturgeon Dwoo library. My problem is I want user create template from the admin panel, it means all template will be stored into database including all Dwoo variable and functions.My questions: Is it possible to load dwoo template from database? How to parse dwoo variable or function from database? I tried to load content from database which is include dwoo var and function inside it, and i have tried to do evaluation using dwoo eval() function and phil sturgeon string_parse() but still have no luck. for example: my controller $data['header'] = "<h1>{$header}</h1>"; --> this could be loaded from database $this->parser->parse('header',$data); my view {$header} Thank you,

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  • Call the cast operator of template base class within the derived class

    - by yoni
    I have a template class, called Cell, here the definition: template <class T> class OneCell { ..... } I have a cast operator from Cell to T, here virtual operator const T() const { ..... } Now i have derived class, called DCell, here template <class T> class DCell : public Cell<T> { ..... } I need to override the Cell's cast operator (insert a little if), but after I need to call the Cell's cast operator. In other methods it's should be something like virtual operator const T() const { if (...) { return Cell<T>::operator const T; } else throw ... } but i got a compiler error error: argument of type 'const int (Cell::)()const' does not match 'const int' What can I do? Thank you, and sorry about my poor English.

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  • Convert templated parameter type to string

    - by wheaties
    I've got a small bit of DRY going on in code I and others have written that I'd like to reduce but I'm failing to figure out how to get it done. This is legacy COM code but it's interfering with the readability. I'd like to do the following: bool queryInterface<class T, class V>(T &_input, V &_output, Logger &_logger){ if( FAILED( _input->QueryInterface( &_output ) ) ){ _logger.error() << "Failed to Query Interface between " << MAGICHAPPENS<T>() << " and " << MAGICHAPPENS<V>(); return false; } if( _output == NULL ){ _logger.warn() << "Unable to Query Interface between " << MAGICHAPPENS<T>() << " and " << MAGICHAPPENS<V>(); return false; } } Wherein the "MAGICHAPPENS()" function would spit out the name of the variable type. Such that if "V" were a IQueryFilter I'd get back a string of "IQueryFilter." I can't think of any reasonable solution without having to write a bunch of template specializations totally defeating the point in the first place. Is there a way to write ANDMAGICHAPPENS?

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  • Architecture for Qt SIGNAL with subclass-specific, templated argument type

    - by Barry Wark
    I am developing a scientific data acquisition application using Qt. Since I'm not a deep expert in Qt, I'd like some architecture advise from the community on the following problem: The application supports several hardware acquisition interfaces but I would like to provide an common API on top of those interfaces. Each interface has a sample data type and a units for its data. So I'm representing a vector of samples from each device as a std::vector of Boost.Units quantities (i.e. std::vector<boost::units::quantity<unit,sample_type> >). I'd like to use a multi-cast style architecture, where each data source broadcasts newly received data to 1 or more interested parties. Qt's Signal/Slot mechanism is an obvious fit for this style. So, I'd like each data source to emit a signal like typedef std::vector<boost::units::quantity<unit,sample_type> > SampleVector signals: void samplesAcquired(SampleVector sampleVector); for the unit and sample_type appropriate for that device. Since tempalted QObject subclasses aren't supported by the meta-object compiler, there doesn't seem to be a way to have a (tempalted) base class for all data sources which defines the samplesAcquired Signal. In other words, the following won't work: template<T,U> //sample type and units class DataSource : public QObject { Q_OBJECT ... public: typedef std::vector<boost::units::quantity<U,T> > SampleVector signals: void samplesAcquired(SampleVector sampleVector); }; The best option I've been able to come up with is a two-layered approach: template<T,U> //sample type and units class IAcquiredSamples { public: typedef std::vector<boost::units::quantity<U,T> > SampleVector virtual shared_ptr<SampleVector> acquiredData(TimeStamp ts, unsigned long nsamples); }; class DataSource : public QObject { ... signals: void samplesAcquired(TimeStamp ts, unsigned long nsamples); }; The samplesAcquired signal now gives a timestamp and number of samples for the acquisition and clients must use the IAcquiredSamples API to retrieve those samples. Obviously data sources must subclass both DataSource and IAcquiredSamples. The disadvantage of this approach appears to be a loss of simplicity in the API... it would be much nicer if clients could get the acquired samples in the Slot connected. Being able to use Qt's queued connections would also make threading issues easier instead of having to manage them in the acquiredData method within each subclass. One other possibility, is to use a QVariant argument. This necessarily puts the onus on subclass to register their particular sample vector type with Q_REGISTER_METATYPE/qRegisterMetaType. Not really a big deal. Clients of the base class however, will have no way of knowing what type the QVariant value type is, unless a tag struct is also passed with the signal. I consider this solution at least as convoluted as the one above, as it forces clients of the abstract base class API to deal with some of the gnarlier aspects of type system. So, is there a way to achieve the templated signal parameter? Is there a better architecture than the one I've proposed?

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