[Qt-interest] Why QListView is so slow and QTableView is fast?

[Justin Noel]

Kenneth Beck wrote:
> Sylvain Pointeau wrote:
>   
>> Hi,
>>
>> I am testing QListView for a large number of items (36'000)...
>> it is so sloooow (I stopped the application, it never shows up) .
>> (yes I set UniformItemSizes to true)
>>
>> I tried QTableView and it is immediate.
>> However the scrolling become slow if we are viewing the last elements.
>>
>> Please can someone give me some insights?
>>
>> Cheers,
>> Sylvain
>>
>>     
> I am having a very similar problem with a QTableView. Once the model is 
> filled and the user is just moving around the table, just moving from 
> one cell to the other, or moving the scroll bar, takes a lot of time. 
> Each call to the data() method requires a search into the model to find 
> the data, but the model only contains a few 10's of items, it is not 
> large. Does anyone know where to look for ways to speed this up? Are 
> there some optimization tricks?
>   

I think the OP is asking the opposite question. How to make QListView
perform as well as QTableView. QTableView in most cases is a  lot
faster. A huge improvement can be gotten by setting
setUniformItemSizes(). Of course to use that you need to make sure all
your items have the same row size.

Good Luck!
--Justin
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