How to delete all rows from QTableWidget

Question

I am trying to delete all rows from a QTableWidget . Here is what I tried.

for ( int i = 0; i < mTestTable->rowCount(); ++i )
{
    mTestTable->removeRo         


        

Answer 1

QTableWidget test;
test.clear();
test.setRowCount( 0);

Answer 2

Just set the row count to 0 with:

mTestTable->setRowCount(0);

it will delete the QTableWidgetItems automatically, by calling removeRows as you can see in QTableWidget internal model code:

void QTableModel::setRowCount(int rows)
{
    int rc = verticalHeaderItems.count();
    if (rows < 0 || rc == rows)
        return;
    if (rc < rows)
        insertRows(qMax(rc, 0), rows - rc);
    else
        removeRows(qMax(rows, 0), rc - rows);
}

Answer 3

Your code does not delete last row.

Try this one.

int totalRow = mTestTable->rowCount();
for ( int i = 0; i < totalRow ; ++i )
{
       mTestTable->removeRow(i);
}

In your code, on the first time, rowCount() have value 2 and value of the i is 0, so its delete 1st row,

But on the second time value of i incremented with 1, but rowCount() return the updated row count which is now 1, so, it does not delete the last row.

Hope now you ll be clear.

Answer 4

Removes all items not in the headers from the view. This will also remove all selections. The table dimensions stay the same.

void QTableWidget::clearContents()

Removes all items in the view. This will also remove all selections and headers.

void QTableWidget::clear()

Answer 5

The simple way to delete rows is to set the row count to zero. This uses removeRows() internally.

table->setRowCount(0);

You could also clear the content and then remove all rows.

table->clearContents();
table->model()->removeRows(0, table->rowCount());

Both snippets leave the headers untouched!

If you need to get rid of headers, too, you could switch from clearContents() to clear().

Answer 6

In order to prevent an app crash, disconnect all signals from the QTableView.

// Deselects all selected items
ui->tableWidget->clearSelection();

// Disconnect all signals from table widget ! important !
ui->tableWidget->disconnect();

// Remove all items
ui->tableWidget->clearContents();

// Set row count to 0 (remove rows)
ui->tableWidget->setRowCount(0);