文章来自:qt帮助文档 检索model/view programming
Using Models and Views
The following sections explain how to use the model/view pattern in Qt. Each section includes an example and is followed by a section showing how to create new components.
Two models included in Qt
Two of the standard models provided by Qt are QStandardItemModel and QFileSystemModel. QStandardItemModel is a multi-purpose model that can be used to represent various different data structures needed by list, table, and tree views. This model also holds the items of data. QFileSystemModel is a model that maintains information about the contents of a directory. As a result, it does not hold any items of data itself, but simply represents files and directories on the local filing system.
QFileSystemModel provides a ready-to-use model to experiment with, and can be easily configured to use existing data. Using this model, we can show how to set up a model for use with ready-made views, and explore how to manipulate data using model indexes.
#include "mainwindow.h"
#include <QApplication>
#include <QSplitter>
#include <QFileSystemModel>
#include <QTreeView>
#include <QListView>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QSplitter *splitter = new QSplitter;
QFileSystemModel *model = new QFileSystemModel;
model->setRootPath(QDir::currentPath());
QTreeView *tree = new QTreeView(splitter);
tree->setModel(model);
tree->setRootIndex(model->index(QDir::currentPath()));
QListView *list = new QListView(splitter);
list->setModel(model);
list->setRootIndex(model->index(QDir::currentPath()));
splitter->setWindowTitle("Two views onto the same file system model");
splitter->show();
return a.exec();
}
The views are constructed in the same way as other widgets. Setting up a view to display the items in the model is simply a matter of calling its setModel() function with the directory model as the argument. We filter the data supplied by the model by calling the setRootIndex() function on each view, passing a suitable model index from the file system model for the current directory.