How can I update a particular QAbstractListModel item?

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I have derived a class FeedItemViewModel from QAbstractListModel. I have implemented a method which adds items in the list model but I do not know how too update an item which has a specific id.

Here is the code:

void FeedItemViewModel::addFeedItem(FeedItem* feedItem)
{
    beginInsertRows(QModelIndex(), rowCount(), rowCount());
    m_feedItems.append(feedItem);
    endInsertRows();
}

void FeedItemViewModel::updateFeedItem(FeedItem* feedItem)
{
    int id = feedItem->id();
    auto iter = std::find_if(m_feedItems.begin(), m_feedItems.end(),
                         [id](FeedItem* item)
                         {
                            return item->id() == id;
                         });
}
2

There are 2 best solutions below

1
On BEST ANSWER

Here is the solution I found:

void FeedItemViewModel::updateFeedItem(FeedItem* feedItem)
{
    int id = feedItem->id();
    auto iter = std::find_if(m_feedItems.begin(), m_feedItems.end(),
                             [id](FeedItem* item)
    {
            return item->id() == id;
    });

    if(iter != m_feedItems.end())
    {
        int indx = m_feedItems.indexOf(*iter);
        m_feedItems[indx] = feedItem;
        dataChanged(index(indx), index(indx));
    }
}
0
On

If you are just updating an item and not replacing it, you could simplify by finding the pointer itself instead of using the id property


void FeedItemViewModel::updateFeedItem(FeedItem *feedItem){
    int indx = m_feedItems.indexOf(feedItem);
    if(indx != -1){
        dataChanged(index(indx), index(indx));
    }
}