img viewer with Qt

Question

I'm trying to create an application based on model/view concept. i need to open some directory, find all imgs in it and show them in MainWindow (subclass of QMainWindow). The architecture is something like this: 1) via QDir create QStringList of "good" file names (using file names filter by extentions). 2) create QStandardItemModel and fill it with QStandardItem (QIcon(QImage(fileName).scaled(QSize)), fileName). 3) use QListView to show data from the model.

but there is some problems. first of all - theModel.columnCount is, e.g., 52 but only one picture is shown on the screen and without its name.

can someone help me: 1) how to fill model correctly? my approach:

QDir dirs(dir);
QStringList imgs = dirs.entryList(QStringList() << "*.jpg" << "*.jpeg" << "*.bmp" << "*.png");

itemModel->clear();

QList<QStandardItem *> listItem;
for(int i = 0; i < imgs.count(); ++i){
    QImage image = QImage(dir + "/" + imgs.at(i)).scaled(QSize(size().width()/4, size().height()/4));

    QStandardItem *item = new QStandardItem();
    item->setIcon(QIcon(QPixmap::fromImage(image)));
    item->setData(imgs.at(i));
    listItem << item;
}
itemModel->appendRow(listItem);

this code is in one slot of the MainWindow class.

2) as I understand, my view is automatically updated, so it should show all data from the model. am I right, or some code is necessary?

3) maybe I haven't done somethings in initialization of the model and the view (the code is in te constructor of class MainWindow):

    itemModel = new QStandardItemModel(this);

    listView = new QListView(this);
    listView->setModel(itemModel);
//    listView->setFlow(QListView::LeftToRight);
//    listView->setLayoutMode(QListView::Batched);
    listView->setViewMode(QListView::IconMode);
    listView->setResizeMode(QListView::Adjust);
//    listView->setGridSize(QSize(size().width()/4, size().height()/4));
    listView->setIconSize(QSize(size().width()/4, size().height()/4));

    setCentralWidget(listView);

You have mistake `itemModel->appendRows(listItem);` instead `itemModel->appendRow(listItem);` — Ruu, May 30 '13 at 07:38
C2039: 'appendRows': is not a member of 'QStandardItemModel' see declaration of 'QStandardItemModel' — Illia Levandovskyi, May 30 '13 at 08:52
appendColumn(listItem) makes all file names viewed. but the problem is still to show imgs, not thouse names. maybe QLabel would be usefull. can someone help me how to do it? — Illia Levandovskyi, May 30 '13 at 09:10

score 0 · Answer 1 · answered Jan 24 '14 at 23:36

Since you determined that you needed appendColumn the last bit would be to add the QIcon as data with the Qt::DecorationRole. The follow works for me for viewing images in the same folder the program is run (though I don't know why it is shown with a grid layout).

#include <QApplication>
#include <QStandardItemModel>
#include <QListView>
#include <QDir>
#include <QStringList>
#include <QList>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QStandardItemModel* itemModel = new QStandardItemModel();
    QListView* listView = new QListView();

    QDir dirs(".");
    QStringList imgs = dirs.entryList(QStringList() << "*.jpg" << "*.jpeg" << "*.bmp" << "*.png");

    QList<QStandardItem *> listItem;
    for(int i = 0; i < imgs.count(); ++i){
        QImage image = QImage(dirs.absoluteFilePath(imgs.at(i))).scaled(QSize(80, 60));

        QStandardItem *item = new QStandardItem();
        item->setData(QVariant(QPixmap::fromImage(image)), Qt::DecorationRole);
        listItem << item;
    }

    itemModel->appendColumn(listItem);

    listView->setModel(itemModel);
    listView->setViewMode(QListView::IconMode);

    listView->show();

    a.exec();
}

img viewer with Qt

1 Answers1