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    Default Re: Advice on what is best to use when displaying lots of numerical data

    Only you understand your requirements. There are a dozen different techniques that could be made to work, some easy, some not so. Some (sort of) fast, some slow. Some that will be pleasing to the eye, many that won't.

    You'll have to try several techniques and see what works for you.

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    Default Re: Advice on what is best to use when displaying lots of numerical data

    QTableView (it is tabular data after all) and a model that supplies your data. You can control read/write ability with the flags method. Checkboxes using the relevant role in the data() call. The model knows when the user changes a value because setData() has to store it. A custom editor for a column can be done with a delegate and QComboBox etc.

    The precise details of the solution are up to you and your customer.

  3. The following user says thank you to ChrisW67 for this useful post:

    Drew (16th May 2011)

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    Default Re: Advice on what is best to use when displaying lots of numerical data

    Thanks Dan - that's a fair call. I suppose what I'm interested in hearing is about any of these dozen different techniques - especially those that don't use any of the things I've mentioned in the OP. Currently I'm learning towards using a QTableView or QTreeView - just want to beware of any potential gotcha's.

    If anyone's used had experience displaying large datasets and had success/problems - I'd be interested to hear their learnings (ie would they recommend it or if they were going to do it again, would they do it differently).

    Cheers

    [Edit] - Thanks also Chris - I was posted this and then saw your response

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    Default Re: Advice on what is best to use when displaying lots of numerical data

    Putting thousands of user interface widgets on display is almost certainly not going to perform well, particularly if many of them are receiving updates rapidly. You may be better off simply painting a grid yourself. If the checkboxes are for display only (not interactive) this would be fast and trivial - just reuse a check image over and over, along with a blank or unchecked image. If you need interactivity, that would take a little more work - but not very much, as it's just a matter of capturing mouse clicks and resolving them to a given rectangular area. This will almost certainly give you the best performance.

    But as others have said, it's really impossible to provide any guidance without more specific requirements.

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    Default Re: Advice on what is best to use when displaying lots of numerical data

    Thousands of data points are better displayed as some sort of graph. I've seen many implementations where details about any particular data point are displayed in a pop-up when you hover the cursor over a point in the graph, eg, if you need to provide access to the detailed data.

    It would also help to know whether you're talking phone (I hope not) or desktop.

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