model view rowCount
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Hello!
I am trying to understand the way in which Table Models work by doing the tutorials provided by Qt, I am facing the problem that I am not able to understand the following code lines:
int rowCount(const QModelIndex &parent = QModelIndex())const override;Your are declaring a method (rowCount) and passing it a const of type QModelIndex pointing to a memory address (&parent) and why is equal to QModelIndex? for me this makes no sense, why pass a memory address to (neither know what parent really means or where it is, I guess it is the parent class).
Can someone (please), explain me this code?
Thank you!
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Hi,
parentif not given when calling the function will contain an invalid index. -
Hello!
I am trying to understand the way in which Table Models work by doing the tutorials provided by Qt, I am facing the problem that I am not able to understand the following code lines:
int rowCount(const QModelIndex &parent = QModelIndex())const override;Your are declaring a method (rowCount) and passing it a const of type QModelIndex pointing to a memory address (&parent) and why is equal to QModelIndex? for me this makes no sense, why pass a memory address to (neither know what parent really means or where it is, I guess it is the parent class).
Can someone (please), explain me this code?
Thank you!
@jss193 said in model view rowCount:
and passing it a const of type QModelIndex pointing to a memory address (&parent)
This not an adress, it's a reference.
rowCount is a abstract method you must implement in your QAbstractTableModel subclass.
The parent ModelIndex is only relevant in a TreeView and not use in a TableView.
