AcceptText method (DataWindows)
Description
Applies the contents of the DataWindow’s edit control
to the current item in the buffer of a DataWindow control or DataStore.
The data in the edit control must pass the validation rule for the
column before it can be stored in the item.
Controls
|
DataWindow type |
Method applies to |
|---|---|
|
PowerBuilder |
DataWindow control, DataWindowChild object, DataStore |
|
Web |
Client control |
|
Web ActiveX |
DataWindow control, DataWindowChild object |
Syntax
[PowerBuilder]
|
1 |
integer <span>dwcontrol</span>.<span>AcceptText</span> ( ) |
[Web DataWindow client control and Web ActiveX]
|
1 |
number <span>dwcontrol</span>.<span>AcceptText</span> ( ) |
|
Argument |
Description |
|---|---|
|
dwcontrol |
A reference to a DataWindow control, |
Return Values
Returns 1 if it succeeds and –1 if it fails (for
example, the data did not pass validation).
If there is no DataWindow object assigned to the DataWindow
control or DataStore, this method returns 1.
Usage
When a user moves from item to item in a DataWindow control,
the control validates and accepts data the user has edited.
How to call AcceptText
When a user modifies a DataWindow item then immediately changes
focus to another control in the window, the DataWindow control does
not accept the modified data—the data remains in the edit
control. Use the AcceptText method in this situation
to ensure that the DataWindow object contains the data the user
edited.
However, you must not call AcceptText in
the LoseFocus event or in a user event posted from LoseFocus if
the DataWindow control still has focus. If you do, an infinite loop
can occur.
The problem
Normally, new data is validated and accepted when the user
moves to a new cell in the DataWindow. If the new data causes an error,
a message box displays, which causes the DataWindow to lose focus.
If you have also coded the LoseFocus event or an event posted from LoseFocus
to call AcceptText to validate data when the
control loses focus, this AcceptText runs because
of the message box and triggers an infinite loop of validation errors.
The solution
It is desirable to validate the last changed data when the control
loses focus. You can accomplish this by making sure AcceptText gets
called only when the DataWindow control really has lost focus. The third
PowerBuilder example illustrates how to use an instance variable
to keep track of whether the DataWindow control has focus. The posted event
calls AcceptText only when the DataWindow control
does not have focus.
This is a change from previous versions of PowerBuilder. Previously,
the posted user event would run while the message box for the validation
error was displayed. Now, it runs after the message box is dismissed,
causing another validation error to occur and another message box
to be displayed, resulting in an infinite loop.
Events
AcceptText can trigger an ItemChanged or
an ItemError event.
AcceptText in the ItemChanged event
Calling AcceptText in the ItemChanged event
has no effect.
Examples
In this example, the user is expected to enter a
key value (such as an employee number) in a column of the DataWindow
object, then click the OK button. This script for the Clicked event
for the button calls AcceptText to validate the
entry and place it in the DataWindow control. Then the script uses
the item in the Retrieve method to retrieve the
row for that key:
|
1 |
IF dw_emp.<span>AcceptText</span>() = 1 THEN |
|
1 |
dw_emp.Retrieve(dw_emp.GetItemNumber & |
|
1 |
(dw_emp.GetRow(), dw_emp.GetColumn())) |
|
1 |
END IF |
This script for the Clicked event for a CommandButton
accepts the text in the DataWindow dw_Emp and counts the
rows in which the column named balance is greater than 0:
|
1 |
integer i, Count |
|
1 |
dw_employee.<span>AcceptText</span>() |
|
1 |
FOR i = 1 to dw_employee.RowCount() |
|
1 |
IF dw_employee.GetItemNumber(i,'balance') & |
|
1 |
> 0 THEN |
|
1 |
Count = Count + 1 |
|
1 |
END IF |
|
1 |
NEXT |
This example illustrates how to validate newly entered
data when the DataWindow control loses focus. An instance variable
keeps track of whether the DataWindow control has focus. It is set
in the GetFocus and LoseFocus events. The LoseFocus event posts
the ue_acceptText event, which calls the AcceptText method
only if the DataWindow control does not have focus.
The instance variable:
|
1 |
boolean dw_has_focus |
The GetFocus event:
|
1 |
dw_has_focus = true |
The LoseFocus event:
|
1 |
dw_has_focus = false |
|
1 |
dw_1.event post ue_acceptText( ) |
|
1 |
The ue_acceptText event:
|
1 |
IF dw_has_focus = false THEN |
|
1 |
dw_1.accepttext( ) |
|
1 |
END IF |