[Qt-interest] QTreeView and custom QAbstractItemModel performance problem

[Felix Brack]

On 08.07.2010 11:45, Sean Harmer wrote:
> Hi,
>
> On 08/07/2010 09:58, Andreas Pakulat wrote:
>> Can you post your model implementation? It sure sounds like you're doing
>> the appending wrong, but without having a look at the code its not
>> possible
>> to say what exactly is wrong.
>>
>> A blind guess could be that you're reset'ting you're model every time you
>> add a row instead of using begin/endInsertRows correctly. See the example
>> models in Qt.
>>
>> Also I'd suggest to use a QTableView instead of QTreeView as that one is
>> significantly faster on non-tree structures (you can tweak it to have no
>> lines etc.) in case you ever get more than 100 rows.
>
> What Andreas says is all true. However if you are using QTreeView a good
> optimisation to use is to tell the view that all rows are the same
> height. With this information the view does nto have to query every row
> of the model to calculate the total height of the viewport for scrollbar
> calculations. See:
>
> http://doc.qt.nokia.com/4.7-snapshot/qtreeview.html#uniformRowHeights-prop
>
> Sean

Hello Sean,

Thanks for the tip but this is what I did first.

Felix