How to reset model in Qt?

Question

I am using Qt model/view framework. When I reset the data in the model, I have to reset the model to let views update also. How to do it? I found a signal modelReset(QPrivateSignal); in the QAbstractItemModel, Is this the way to solve it? How to emit the signal? Thanks.

Worth to mention that there are other methods that help to update views. All depends on what changes are made. Model reset is useful when you're performing big canges in model. There is `beginInsertRow`, `beginMoveRows`, `beginRemoveRows`. All those methods also apply to columns. So if you're going to perform small changes don't use `beginResetModel` as it will rebuild whole model in view instead of applying small changes on view. — Kamil Klimek, Feb 08 '13 at 08:42

score 19 · Accepted Answer · answered Feb 07 '13 at 17:10

19

You call beginResetModel() before you reset your data, and then endResetModel() once you have finished. The endResetModel() emits the private signal.

answered Feb 07 '13 at 17:10

cmannett85

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Thanks, that did it. – Borzh Apr 07 '17 at 23:56

score 3 · Answer 2 · answered Feb 07 '13 at 17:21

As you can see here, the preferred method is to use the beginResetModel() and endResetModel() functions surrounding your reset code in your model subclass.

This should handle emitting the signal appropriately.

Some of the qabstractitemmodel subclasses might allow you to use model.removeRows(0,model.rowCount()) (others would require you to implement it yourself)

How to reset model in Qt?

2 Answers2