QDirModel and run a file depend of the filetype

[TomASS]

i'm showing a dir content by:

QDirModel *model = new QDirModel;
    QTreeView *tree = new QTreeView();
    tree->setModel(model);
    tree->setRootIndex(model->index(QDir::currentPath()));
    layout->addWidget(tree,0,0,1,1);

QDirModel *model = new QDirModel;
    QTreeView *tree = new QTreeView();
    tree->setModel(model);
    tree->setRootIndex(model->index(QDir::currentPath()));
    layout->addWidget(tree,0,0,1,1);

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And the question is - how to "run" a file whith is clicked in application depend of the filetype (example like in windows)