Category Archives: Models

Jongling models beetween threads

We know that in Qt the models are not thread-safe – they totally depend on your implementation. So what we may do to bypass model between threads? Guess that we have some models which implementation we can not adjust much or can not make thread-safe. Danger is that if some model is used somewhere (pointer […]
Also posted in Blog, Boost, C++, Qt | 3 Comments

Designing tree-like models

We found that developers are often confused about implementing tree-like models using Qt classes. Now we can show some tricks and considerations about the way of designing them. First for some refreshment, let’s remind what you have for addressing the elements in the model. This is QModelIndex, which have pointer to model that created the […]
Also posted in Blog, C++, Qt, Research | 2 Comments

Overhead cost of using Qt models

I decided to run very simple test to have glance on performance of Qt models and overhead cost of using them. Something very simple as make 1M random strings with random size (note: rnd_str(int) return some random string with specified size)
Also posted in Blog, C++, Qt, Research | 3 Comments

About Boost Multi-index Containers

I really like Qt Template Library (QTL), but still have lack of some important functionality which is usually called multi-index. Anyway there is very powerful implementation existing in Boost. I really need these templates to establish relations between different data structures. I often use it as internal “engine” for different Proxy models that I use […]
Also posted in Blog, Boost, C++, Qt, Research | 3 Comments

Jongling Qt models 2, Composition Gem

We are back to models again :). In Qt you may find a lot of flexibilities for Model-View programming. Especially due to proxies to do filtering, sorting or even rearranging data (see Jongling Qt models) to be organized in any way that is good for you. You can have one data source model which you […]
Also posted in Qt, Research | 6 Comments

Jongling Qt models

When you work intensively with data in your application then soon or not but you will realize that the best way of keeping them is some model object inherits from QAbstractItemModel, then data are hidden inside implementation of model. Adding, removing and modification are accessible through your API of the model class and it calls […]
Also posted in Blog, Qt, Research | 6 Comments