2 ways to get data from model

[Higgs]

Hi all.
I'm learning from Johan Thelin's book(based on Qt 4.x) and there is written that,to get data from model we use:

int value2 = index.model()->data(index,Qt::DisplayRole).toInt();

int value2 = index.model()->data(index,Qt::DisplayRole).toInt();

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But in documentation(Qt 5.1.1) there is another way:

int value = index.data().toInt();

int value = index.data().toInt();

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Both work for me very well. But what is the difference? Which one I should use?

[Infinity]

I would use the second version because it is shorter. You don't need to use the index twice. Apart from that there's not much difference.
There are also a lot of other convenience functions all over the Qt framework.

[anda_skoa]

Ultimately all calls for data end up in the model's data() method.

As Infinity wrote, QModelIndex::data() is just a short hand for getting the pointer to the model and calling its data() method.

Cheers,
_