Getting value from QTableWidgetItem

Question

I want to set QTableWidgetItem's data as an image. imagePath may be different each time.

QTableWidgetItem *itemMedia = new QTableWidgetItem();
itemMedia->setTextAlignment(Qt::AlignCenter);
itemMedia->setData(Qt::DecorationRole, QPixmap(imagePath).scaled(width, 100, Qt::KeepAspectRatio, Qt::SmoothTransformation));
m_table->setItem(0,0,itemMedia);
m_table->setItem(0,1,itemMedia);
m_table->setItem(1,0,itemMedia);
m_table->setItem(1,1,itemMedia);

I've created it nicely. Next, I want to get data with this:

connect(m_table, SIGNAL(itemClicked(QTableWidgetItem *)), this, SLOT(onItemClicked(QTableWidgetItem *)));

void MUCSharedMedia::onItemClicked(QTableWidgetItem *item)
{
    qDebug()<<"DecorationRole: " <<item->data(Qt::DecorationRole).toString();
    qDebug()<<"DisplayRole: " <<item->data(Qt::DisplayRole).toString();
}

Actually I want imagePath in one of this role , but I get this line in Application Console:

DecorationRole:  ""
DisplayRole:  ""

How to get value? Any suggestion?

EDITED: I want to show image on each QTableWidgetItem after that I want to store image path of images which I've shown.

Do you want to store imagePath as string in each item? Then try to use DisplayRole in both cases? Or you want to store actual image, please clarify — demonplus, Dec 01 '15 at 11:50

Acha Bill · Answer 1 · 2015-12-01T12:36:30.737

1

QTableWidgetItem::data() returns QVariant where you'll get the data with QVariant::value().

Alternatively, use QTableWidget::text().

http://doc.qt.io/qt-5/qtablewidgetitem.html

edited Dec 01 '15 at 12:36

answered Dec 01 '15 at 11:44

Acha Bill

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demonplus · Accepted Answer · 2015-12-01T14:53:13.120

1

If you need to store QString actually, you need DisplayRole two times:

itemMedia->setData(Qt::DisplayRole, imagePath);

qDebug()<<"DisplayRole: " <<item->data(Qt::DisplayRole).toString();

EDIT: if you need to show image and get image file path I suggest you another way:

1) Set image like you did:

itemMedia->setData(Qt::DecorationRole, QPixmap(imagePath).scaled(width, 100, Qt::KeepAspectRatio, Qt::SmoothTransformation));

2) Set image path using Qt::UserRole

itemMedia->setData(Qt::UserRole, imagePath);

When you need it:

qDebug()<<"File Path: " <<item->data(Qt::UserRole).toString();

But application will use image for displaying.

edited Dec 01 '15 at 14:53

answered Dec 01 '15 at 11:56

demonplus

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I answered about QImage from filepath but same way you can get related image class you need – demonplus Dec 01 '15 at 12:39
I want to setData as an actual image and get data as a qstring – Farzan Najipour Dec 01 '15 at 13:07
@afn: you said from the very beginning you want to store imagePath in each item – demonplus Dec 01 '15 at 13:08
yes, but it was just last part. I want to show image on each QTableWidgetItem after that I want to store image path of images which I've shown. – Farzan Najipour Dec 01 '15 at 13:10
Could you please edit your question with all these details so it would be clear what you actually need? – demonplus Dec 01 '15 at 13:11
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/96682/discussion-between-afn-and-demonplus). – Farzan Najipour Dec 01 '15 at 13:12
@afn I added information which you wanted to my answer – demonplus Dec 01 '15 at 14:53

score 1 · Answer 3 · answered Dec 01 '15 at 15:34

You store a QPixmap:

itemMedia->setData(Qt::DecorationRole, QPixmap(imagePath).scaled(width, 100, Qt::KeepAspectRatio, Qt::SmoothTransformation));

but try to extract it as a QString:

qDebug()<<"DecorationRole: " <<item->data(Qt::DecorationRole).toString();

That will always give you a default-constructed (i.e. empty) QString.

You want to retrieve it as a QPixmap:

item->data(Qt::DecorationRole).value<QPixmap>()

(though there's little point sending that to a QDebug stream!)

There's a good chance you want the original, unscaled pixmap. In which case, you'll need to store that as well, perhaps in Qt::UserRole:

itemMedia->setData(Qt::UserRole, QPixmap(imagePath));

and change the retrieval to match.

Getting value from QTableWidgetItem

3 Answers3