Thumbnail View

Have a list of instances of a structure, you might want to add some more info later and there is no point in redesigning everything then. Or just use QStandardItemModel.

That's a good idea. The problem with QStandardItems is that it must store the whole path, but show only the name in the view.

Also, how do I avoid starting huge amounts of the concurrent thumbnail functions at once? Or is it OK?

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Originally Posted by MTK358

The problem with QStandardItems is that it must store the whole path, but show only the name in the view.

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Sorry? There is Qt::DisplayRole for what gets shown and an infinite number of custom roles you can use for any data you want (such as the full path).

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Also, how do I avoid starting huge amounts of the concurrent thumbnail functions at once? Or is it OK?

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It's ok, they will be queued.

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Originally Posted by wysota

Sorry? There is Qt::DisplayRole for what gets shown and an infinite number of custom roles you can use for any data you want (such as the full path).

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How am I supposed to do that when I'm not using a custom model?

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Originally Posted by wysota

It's ok, they will be queued.

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They will be queued automatically without me taking any action?

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Originally Posted by MTK358

How am I supposed to do that when I'm not using a custom model?

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You can pass any integer equal or larger than Qt::UserRole as the role for any method accepting a role identifier.

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They will be queued automatically without me taking any action?

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Yes. QtConcurrent will only run concurrently at most as many jobs as you have cores available in your machine (so 1 task for 1 core, 2 tasks for 2 cores, etc.), excluding the main execution thread (so Qt Concurrent guarantees that at least one job will be ran). The remaining jobs will be queued until there are idle threads available.

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Originally Posted by wysota

You can pass any integer equal or larger than Qt::UserRole as the role for any method accepting a role identifier.

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So you can add a non-visible piece of data to be used internally by your program to a QStandardItem?

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Originally Posted by wysota

Yes. QtConcurrent will only run concurrently at most as many jobs as you have cores available in your machine (so 1 task for 1 core, 2 tasks for 2 cores, etc.), excluding the main execution thread (so Qt Concurrent guarantees that at least one job will be ran). The remaining jobs will be queued until there are idle threads available.

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OK, that's nice.

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Originally Posted by MTK358

So you can add a non-visible piece of data to be used internally by your program to a QStandardItem?

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Yes, that's correct.

Code:

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enum { myCustomStringRole = Qt::UserRole+1, myCustomColorRole };
//...
QStandardItem *item = ...
item->setData("my custom string", myCustomStringRole);
item->setData(QColor("red"), myCustomColorRole);

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