datagrids.md

Data grids

Getting column values from the UI Selected Item

Add a Runtime NetLogic as children of the DataGrid, add the following NetLogic and invoke the DataGridSelectionChanged method in the User selection changed event of the DataGrid itself, remember to pass the NodeId of the DataGrid as argument of the function (to make it session-independent). The UI Selected Item is actually an object which has a children variable per each column of the DataGrid.

[ExportMethod]
public void DataGridSelectionChanged(NodeId dataGrid)
{
    // Session variables where to store the output of the SelectedItem
    var sessionClientId = Session.GetVariable("selectedClientId");
    var sessionUsedCnt = Session.GetVariable("selectedUsedCnt");
    var sessionLastUsedTime = Session.GetVariable("selectedLastUsedTime");

    // Retrieve the DataGrid object
    var dataGridItem = InformationModel.Get<DataGrid>(dataGrid);
    if (dataGridItem == null)
    {
        Log.Error("DataGrid is null");
        return;
    }

    // Get the UI Selected Item variable (an object)
    var selectedRow = InformationModel.Get(dataGridItem.UISelectedItem);
    if (selectedRow == null)
    {
        Log.Error("Selected row is null");
        return;
    }

    // Get the value at the column called "ClientID" (string)
    var selectedRowClientId = selectedRow.Children.OfType<IUAVariable>().FirstOrDefault(x => x.BrowseName == "ClientID");
    if (selectedRowClientId == null)
    {
        Log.Error("ClientID is null");
        return;
    }

    // Get the value at the column called "Used" (Bool)
    var selectedRowUsedCnt = selectedRow.Children.OfType<IUAVariable>().FirstOrDefault(x => x.BrowseName == "Used");
    if (selectedRowUsedCnt == null)
    {
        Log.Error("Used is null");
        return;
    }

    // Get the value at the column called "LastUsedTime" (DateTime)
    var selectedRowLastUsedTime = selectedRow.Children.OfType<IUAVariable>().FirstOrDefault(x => x.BrowseName == "LastUsedTime");
    if (selectedRowLastUsedTime == null)
    {
        Log.Error("LastUsedTime is null");
        return;
    }

    // Set the variables in the editor object
    sessionClientId.Value = selectedRowClientId.Value.Value.ToString();
    sessionUsedCnt.Value = Convert.ToInt32(selectedRowUsedCnt.Value.Value.ToString());
    sessionLastUsedTime.Value = Convert.ToDateTime(selectedRowLastUsedTime.Value.Value.ToString());
}

Interacting with the content of a DataGrid

[ExportMethod]
public void UpdateDataGridValues()
{
    // Retrieve the DataGrid object
    DataGrid dg = (DataGrid)Owner;
    // Get the "Models" object which is the parent of all the rows of the DataGrid
    IUAObject t = dg.Children.GetObject("Models");

    // Get all rows as a list
    List<UAVariable> rows = new List<UAVariable>();
    foreach (var child in t.Children)
    {
        if (child is UAVariable variable)
            rows.Add(variable);
    }

    double previousEl = 0;
    double previousGas = 0;
    double previousWater = 0;
    double previousSteam = 0;

    // Row 0: header of the grid
    // Row 1: selected item
    // Row 2 and following: actual content of the grid, where each row is an object with a variable per each column of the grid
    for (int i = 2; i < rows.Count; i++)
    {
        var row = rows[i];
        // Get all columns as a list
        List<UAVariable> cols = new List<UAVariable>();
        foreach (var child in row.Children)
        {
            if (child is UAVariable variable)
                cols.Add(variable);
        }
        DateTime timestamp = (DateTime)cols[0].Value;
        if (timestamp.Minute == 0 && i > 0)
        {
            // Edit the value of a column by name
            previousEl = UpdateDGField(ref cols, 2, previousEl);
            previousGas = UpdateDGField(ref cols, 3, previousGas);
            previousWater = UpdateDGField(ref cols, 4, previousWater);
            previousSteam = UpdateDGField(ref cols, 5, previousSteam);
        }
    }
}

private double UpdateDGField(ref List<UAVariable> cols, int i, double prev)
{
    double current = Convert.ToDouble(cols[i].Value);
    if (current >= prev)
        cols[i+4].Value = current - prev;
    else
        cols[i+4].Value = (current + 32767) - prev;
    prev = current;
    return prev;
}