QTreeWidget: how to prevent selection change by user

[Diracsbracket]

Hi,
I am using a QTreeWidget as a multi-column list. The row selection within the widget is controlled by a script, which sequentially processes a row at the time, selecting it in the process to provide feedback to the user as to which row is being processed.

I want to prevent the user of making any selection: the selection may only be done by the program, but the user may still scroll the list to see other rows.

How can I achieve this?

Thanks!

[Chrisw01]

Hi,

Take a look at selectionMode and or setSelectionMode. I'm not sure if this would disable it for just the user or both user and system.

[SGaist]

Hi,

Then why not disable the widget while the processing is being done ?

[Diracsbracket]

This post is deleted!

[Diracsbracket]

@Chrisw01 said in QTreeWidget: how to prevent selection change by user:

setSelectionMode

Setting setSelectionMode to NoSelection also disables selection higlighting by the code.

[Diracsbracket]

@SGaist If I disable the widget, the scroll does not work, and I need to override the stylesheet to give the disabled widget the same look as the enabled one (which is not a big deal, I suppose).

[SGaist]

Then you can install an event filter that will eat the keys and mouse related events.

[VRonin]

@Diracsbracket said in QTreeWidget: how to prevent selection change by user:

Setting setSelectionMode to NoSelection also disables selection higlighting by the code

How do you implement the "higlighting by the code"?

[Diracsbracket]

@VRonin said in QTreeWidget: how to prevent selection change by user:

How do you implement the "higlighting by the code"?

Just by selecting the row using setCurrentItem.

ui->treeWidget->setCurrentItem(ui->treeWidget->topLevelItem(scriptLineIndex));

The default styleSheet for the selected state (which you can override) applies then, which is different from the not-selected state.

[Diracsbracket]

I finally chose the following option:
I made all items in the QTreeWidget enabled, but non-selectable:

itm->setFlags(Qt::ItemIsEnabled);

This still allows for row highlighting upon mouse hovering, which is good, and I can still scroll the list.

Then, using two variables to hold the indices of the currently selected row, and the previously selected row, I apply my formatting directly:

• the currently selected row is highlighted
• the color formatting of the previously selected row is restored

    setRowColor(prevLineIndex, Qt::white, Qt::black);
    setRowColor(scriptLineIndex, Qt::blue, Qt::white);

setRowColor does the following:

void MainWindow::setRowColor(int rowIndex, const QColor& backColor, const QColor& textColor)
{
    if ((rowIndex<0) || (rowIndex>=numLines))
        return;

    for (int i=0; i<UM_NUM_TW_COL;i++)
    {
        ui->treeWidget->topLevelItem(rowIndex)->setBackgroundColor(i, backColor);
        ui->treeWidget->topLevelItem(rowIndex)->setTextColor(i, textColor);
    }
}

Thanks for your feedback everyone!