How to delete all rows from QTableWidget
C++QtQtablewidgetC++ Problem Overview
I am trying to delete all rows from a QTableWidget . Here is what I tried.
for ( int i = 0; i < mTestTable->rowCount(); ++i )
{
mTestTable->removeRow(i);
}
I had two rows in my table. But this just deleted a single row. A reason could be that I did not create the the table with a fixed table size. The Qt Documentation for rowCount() says,
> This property holds the number of rows in the table. > > By default, for a table constructed without row and column counts, > this property contains a value of 0.
So if that is the case, what is the best way to remove all rows from table?
C++ Solutions
Solution 1 - C++
Just set the row count to 0 with:
mTestTable->setRowCount(0);
it will delete the QTableWidgetItem
s 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);
}
Solution 2 - C++
I don't know QTableWidget
but your code seems to have a logic flaw. You are forgetting that as you go round the loop you are decreasing the value of mTestTable->rowCount()
. After you have removed one row, i
will be one and mTestTable->rowCount()
will also be one, so your loop stops.
I would do it like this
while (mTestTable->rowCount() > 0)
{
mTestTable->removeRow(0);
}
Solution 3 - C++
AFAIK setRowCount(0)
removes nothing. Objects are still there, but no more visible.
yourtable->model()->removeRows(0, yourtable->rowCount());
Solution 4 - C++
QTableWidget test;
test.clear();
test.setRowCount( 0);
Solution 5 - C++
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()
.
Solution 6 - C++
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);
Solution 7 - C++
Look this post : http://forum.qt.io/topic/1715/qtablewidget-how-to-delete-a-row
QList<QTableWidgetItem*> items = table.findItems(.....);
QMap<int, int> rowsMap;
for(int i = 0; i < items.count(); i++{
rowsMap[items.at(i).row()] = -1; //garbage value
}
QList<int> rowsList = rowsMap.uniqueKeys();
qSort(rowsList);
//Now go through your table and delete rows in descending order as content would shift up and hence cannot do it in ascending order with ease.
for(int i = rowList.count() - 1; i >= 0; i--){
table.removeRow(rowList.at(i));
}
Solution 8 - C++
You can just add empty item model (QStandardItemModel) to your QTableView (myTableView):
itemModel = new QStandardItemModel;
ui->myTableView->setModel(itemModel);
Solution 9 - C++
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 1
st 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.
Solution 10 - C++
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()
Solution 11 - C++
This works for me:
for i in reversed(range(self.tableWidget.rowCount())):
self.tableWidget.removeRow(i)
Solution 12 - C++
In python
you can just set the rowCount to zero and that'll work!
tableWidget.setRowCount(0)
This code is tested with PySide6. Hope it will work for PyQt5 and PyQt6 too.