RowFocusChanging – PB Docs 2022

Description

Occurs when the current row is about to change in the DataWindow.
(The current row of the DataWindow is not necessarily the same as the
current row in the database.)

The RowFocusChanging event occurs just before the RowFocusChanged
event.

PowerBuilder event
information

Event ID: pbm_dwnrowchanging

Return Values

Set the return code to affect the outcome of the event:

0 — Continue processing (setting the current row)

1 — Prevent the current row from changing

For information on setting the return code in a particular
environment, see About return
values for DataWindow events.

Usage

Typically the RowFocusChanging event is coded to respond to a mouse
click or keyboard action that would change the current row in the
DataWindow object. The following methods can also trigger the
RowFocusChanging event, as well as the RowFocusChanged and
ItemFocusChanged events, when the action changes the current row:

In these cases, the RowFocusChanging event script can prevent the
changing of the DataWindow object’s current row only. The script cannot
prevent the data from being changed (for example, the rows still get
moved).

When you use the ScrollToRow method to change focus, the
RowFocusChanging event is triggered before the scroll occurs, and the
RowFocusChanged event is triggered after the scroll occurs.

In a tabular DataWindow, if the user clicks to change rows, the row
focus does not change, and the row and DataWindow do not scroll. You can
still scroll programmatically or by using the scroll bar.

In a read-only DataWindow, when you click on any column that is not
in the current row, the RowFocusChanging and RowFocusChanged events fire,
but the current column is not changed — the current column remains at 0,
since no column can have focus. DataWindows are read-only if updates are
not allowed, all tab orders are set to 0, or all tab columns are
protected.

However, if focus is on an editable column in an updatable
DataWindow (a DataWindow that has one or more editable columns), the row
focus events do not fire when you click on a protected column or on a
column whose tab order is 0. The focus remains on the current, editable
column.

If focus moves off an editable column in an updatable DataWindow,
the DataWindow switches to read-only mode. This can happen when the last
row in the DataWindow does not have an editable column. In this case,
tabbing off the last editable column causes the row focus to move to the
row following the row with the last editable column. The DataWindow then
remains in read-only mode until focus is given to an editable
column.

Examples

This example displays a message alerting you that changes have been
made in the window dw_detail which will be lost if the row focus is
changed to the window dw_master.

See also

ItemFocusChanged

RowFocusChanged