QItemSelection 类

详细说明

A QItemSelection describes the items in a model that have been selected by the user. A QItemSelection is basically a list of selection ranges, see QItemSelectionRange. It provides functions for creating and manipulating selections, and selecting a range of items from a model.

The QItemSelection class is one of the Model/View Classes and is part of Qt's model/view framework.

An item selection can be constructed and initialized to contain a range of items from an existing model. The following example constructs a selection that contains a range of items from the given model, beginning at the topLeft, and ending at the bottomRight.

QItemSelection *selection = new QItemSelection(topLeft, bottomRight);

An empty item selection can be constructed, and later populated as required. So, if the model is going to be unavailable when we construct the item selection, we can rewrite the above code in the following way

QItemSelection *selection = new QItemSelection();
...
selection->select(topLeft, bottomRight);

QItemSelection saves memory, and avoids unnecessary work, by working with selection ranges rather than recording the model item index for each item in the selection. Generally, an instance of this class will contain a list of non-overlapping selection ranges.

Use merge() to merge one item selection into another without making overlapping ranges. Use split() to split one selection range into smaller ranges based on a another selection range.