@VRonin Thanks, a written example is a lot easier to understand. I was going through the Qt documentation over and over and couldn't find an good example for this.

@VRonin Thanks. It worked. We have used delegates because we have combobox, lineedit also. So we have put check for combobox, not to update via delegate.

@VRonin yea, ty, already fix it

@Bonnie said in Trying to programatically fill a model for QTableView: Yes, the life cycle is definitely a problem. You should show the code when making the tabletModel a member of MainWindow. And there's no need to call show() when appending data. It turns out I was not initializing the table model in the constructor when making it a member. and you are correct the show() isn't needed. Now it all works. Thanks again!

Although I still don't understand why setData returns false after the first selected row, this works. Thank you!

So I tried the suggestions by @jwernerny. I dumped the QSqlQueryModel and went with a QStandardItemModel. TableView now displays correctly. Code now looks like this: void MainWindow::on_btnLoadTable_clicked() { conn = new Connection("LOCALHOST\\SQLEXPRESS", "Plants"); stdModel = new QStandardItemModel(this); conn->init(); //Set driver and connection options conn->open(); qry1 = new QSqlQuery(conn->db); const int COL_COUNT = 3; if (qry1->exec("spBatchesPerPlant")) { qDebug() << "Executing query..."; int row = 0; //used for counting rows in the query while (qry1->next()) //Loop through the results { for (int col = 0; col < COL_COUNT; col++) { stdItem = new QStandardItem(qry1->value(col).toString()); stdModel->setItem(row, col, stdItem); } row++; } ui->tableView->setModel(stdModel); } } Motto of the story: stored procedures generate forward only queries. QSqlQueryModel does not work for forward only queries, so use a standard item (or custom) model.

@vronin that looks like exactly it, thanks for the link! The translation shouldn't be a problem, most of the qt documentation is written in c++ anyway. Is there a way to mark your post as the answer instead?

@JonB I added comments in my code. I think I should explain it clearly. Sorry... but please help.

Yes you do, or you can make your own custom QAbstractTableModel that will return the content of your vector of records. Yes you do. However you can use an in-memory database if you don't want to have another database in a file.

@SGaist said in Add Qlabel as item in QTableview: QStyledItemDelegate Ok..I'll try with that. from google search maybe this kind of output it will give, which maybe as our requirement. Else, I have some lengthy approach..implement custom label with mousepressevent handled which emits the object name and add these custom labels, 20 in HLayout and add hlayouts in a vlayout... Thanks!

Hi! Thank you very much for your help. I thought and I want to make little steps at first, so I changed my struct: // person.h struct person { int id; QStandardItem* name; QStandardItem* family; } Now I can directly use my members and append them. I do not need write access, but to show my objects directly in QAbstractTableModel is indeed a sexy idea. I am trying around with QModelIndex, club_model->item(), club_model->itemData() and roles, and when I am done with that, maybe I'll try my own model. For now, my question is solved! Regards Gerhard

Unfortunately it seems that it's not enough to trigger the scrollbar of the parent. The solution I found is to set the fixedWidth of the table like this : int size{ 0 }; for (int i = 0; i < table->columnCount(); ++i) size += table->columnWidth(i); table->setFixedWidth(size);

So my final solution is: class SqlRelationalDelegate : public QSqlRelationalDelegate { Q_OBJECT public: StorageSqlRelationalDelegate(QObject* parent = nullptr) : QSqlRelationalDelegate(parent) {} QWidget* createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const override { editor = QSqlRelationalDelegate::createEditor(parent, option, index); return editor; } void destroyEditor(QWidget* editor, const QModelIndex& index) const override { QSqlRelationalDelegate::destroyEditor(editor, index); this->editor = nullptr; } QWidget* getEditor() const { return editor; } private: mutable QWidget* editor = nullptr; }; ... class TableView : public QTableView { Q_OBJECT public: StorageTableView(QWidget* parent = nullptr) {} void openPersistentEditor(const QModelIndex &index) { QTableView::openPersistentEditor(index); emit persistentEditorOpened(index); } signals: void persistentEditorOpened(const QModelIndex &index); }; ... connect(view, &TableView::persistentEditorOpened, [view] (const QModelIndex& index) { auto model = view->model(); auto delegate = qobject_cast<SqlRelationalDelegate*>(view->itemDelegate(index)); if (!delegate) qFatal("Delegate cast error"); delegate->setModelData(delegate->getEditor(), model, index); });

@VRonin That's really useful, thank you very much. Also I didn't know about the "Model test", that's nice too.

I'll update this post once I go anywhere with it This feedback sounds promising. I am becoming more curious around another description for a similar use case: An associative table can be created. QStandardItem objects can be generated then based on table entries. Which ways would you like to recommend for the connection of entities to their relationship data?

@MrBolton Thanks for replying. Your solution is not what I am looking for, unfortunately. I do not even have a QSortFilterProxyModel. Specifically, I do not want sorting to happen at the client. I wish it to happen at the server with a ORDER BY. My problem, IIRC, is that QTableView::setSortingEnabled(true); QTableView::sortByColumn(col, Qt.DescendingOrder); causes two SQL queries to be sent to the database, one for each line. Reversing the order of the two lines does not help. According to me, it is therefore not possible to enable sorting and pick which column to sort by without executing two queries in a row, which is ridiculously wasteful since we only care about the result of the second query. Users may not even be aware that this is what is happening behind the scenes. There should surely be some way of enabling sorting and specifying the column+direction without issuing two separate queries to the database. Nobody else but me seems to think this is an issue/bad/wrong! I realise this question is now OT. If you would care to share your help on this matter please be kind enough to post in my original thread, https://forum.qt.io/topic/83294/how-to-prevent-qtableview-qtreeview-doing-query-sorting-multiple-times. Thank you.

What's the problem replacing the QSpinBox with a QComboBox in the example? Did you even try?

Do you mean custom graphicsView or tableView? If custom graphics view wouldn't it be too hard to reimplement everything? Any links or example would help.

@JonB This adds a new, blank row at the end of the table model. But you do not set that row to hold your component / text? How to do it? I did not correctly understand what this function does, so if it's not hard for you. You can suggest how to insert text in the first free cell

@Arthur-Araruna said in Replicate the contents of the current selected item in QTableView: both column and row indices All you need to do is replace currentRowChanged with currentIndexChanged

I created custom model which works fast enough. It fetches and writes data using queries. Seems like working solution.

@mmikeinsantarosa Hi just to be clear You do not name the parameter when using a function in a connect. Nor for signal OR the slot. So if you function is like void MySlot( int ID, QString Name) ( in .h and cpp) you would only use as MySlot( int, QString) for connect.

Hi it will only be a problem if you make too long lasting loop. Then it will stop redrawing.

You could set default sorting column to -1 by QHeaderView::setSortIndicator like this yourTableView->horizontalHeader()->setSortIndicator(-1, Qt::AscendingOrder); before running yourTableView->setSortingEnabled(true); because QTableView::setSortingEnabled uses QHeaderView::sortIndicatorOrder and QHeaderView::sortIndicatorSection to identify by which column should model be sorted. Note that documentation of QHeaderView::setSortIndicator tells that not all models support setting sort column to -1 and may even crash in this case.

@VRonin I got it corrected! searchProxy->setSourceModel(modal); ui->tableView->setModel(searchProxy); should be put inside the search button method!

The answer in stackoverflow is correct. Is there no other way to get notified when an Edit begins? just declare and emit your custom signal in the delegate subclass Remember 1 model can service multiple views so, normally, the model should not depend on the state of the view or delegate

@Kushan Or you can use resizeColumnsToContents() method for the same.

You can use either QTreeWidget, QTableWidget, QTreeView+QStandardItemModel, QTableView+QStandardItemModel, QTreeView+QAbstactTableModel subclass, QTableView+QAbstactTableModel subclass for what you are trying to do. I would go with a QT*View+QStandardItemModel (tree or table doesn't matter). The functionalities you describe are: only some columns will be editable use QStandardItem::setFlag Entering a value in the cents column (a logarithmic measure of frequency) will change the value in the hertz column, and vice versa connect a slot to QStandardItemModel::dataChanged signal There will be a button next to the table to add an additional note to the scale connect a slot that calls QStandardItemModel::insertRows to the QPushButton::clicked signal

Так проверьте соединение при запуске. И может, драйвер для SQLite собран только дебаговый? Надо и релизный тоже собрать.

@MrBolton Sorry, I really don't understand your comment. Precisely the point is that with "bigger data sets" you would have to fetch all the data, which is incredibly slow and may well exceed available memory. (OTOH, if the dataset is "small" the overhead of re-query compared to holding all the previous rows locally is also "small".) As a rule of thumb, one always wants as much work to be done at the server side as possible, not client side. Let's say the table has a million rows and the query I want to pose is: SELECT * FROM table ORDER BY column LIMIT 100 Very approximately, pushing the ORDER BY to the server instead of into a QSortFilterProxyModel will run 10 thousand times faster and use one ten-thousandth of the client memory. That's why I would be very careful before advising people to use QSortFilterProxyModel without understanding the ramifications!

Thanks everyone for answer. I am end up with write my own models, the load time reduce to 3s for 30k row and 150 col each.

Put a QSortFilterProxy model in-between. then save from the proxy instead of the main model. P.S. connect(currentTableHeader, SIGNAL(sectionClicked(int)), this, SLOT(on_sectionClicked(int))); and void mainWidget::on_sectionClicked(int index) are useless. this is the default behaviour of QTableView, you don't have to implement it manually

Did you already checked the bug report system to see if there was something related ? If not, please consider opening a new report providing a minimal compilable example showing the behaviour.

You might get error is the following statement, since ui is not included ui->MWtextEdit->setText(text) which can be got ridden by adding following syntax in in mainwindow.h #include "ui_mainwindow.h"

In 90% of the cases you can use QStandardItemModel instead of going through the minefield that is subclassing an abstract model. My advice is just to use that "universal model" instead of a custom one. If you really, really want to customise it as performance of QStandardItemModel is a problem then make sure you run your model through the Model Test (needs just a couple of trivial fixes to work on Qt5) that will tell you if you did everything as you were supposed to or you fell in the countless pitfalls of model subclassing