borland Packages  Class Hierarchy  dx.dataset Package 

ColumnChangeListener interface

java.util.EventListener
   +----com.borland.dx.dataset.ColumnChangeListener

About the ColumnChangeListener interface

Methods  

Implemented by ColumnChangeAdapter

This interface is used for notification that data has changed in a column. One listener can be written for each column, or for an entire StorageDataSet, for which you want to be notified of changes. This is the listener to use for checks on field values that should be done before a user leaves the field. One example of when this might be useful is to check that a part number is in stock before the rest of the line item information is entered. Writing a listener for a StorageDataSet enables it to be called for all columns.


ColumnChangeListener methods

Methods defined in this interface


ColumnChangeListener methods

changed(com.borland.dx.dataset.DataSet, com.borland.dx.dataset.Column, com.borland.dx.dataset.Variant)

  void changed(DataSet dataSet, Column column, Variant value)
Called after all column level validations have been performed and a column value has been successfully posted inside a ReadWriteRow.

Parameters:

dataSet
Which data set contains the column that has data that has been accepted as a valid field value.
column
Which column has data that has been changed and verified as valid.
value
The new, valid value of the data in the column that changed.

validate(com.borland.dx.dataset.DataSet, com.borland.dx.dataset.Column, com.borland.dx.dataset.Variant)

  void validate(DataSet dataSet, Column column, Variant value)
Called before column level validations like readOnly, min, or max are performed, and before the new value is recorded in a ReadWriteRow. Note that if values are set programmatically, EditMask constraints are not applied. You can change the value stored in value, but it must still pass the column level validations. To prevent the value from being set, throw an Exception. If an Exception is constructed with a String parameter, this String is used in the default error handling display, for example,
throw new Exception("My error message");

Parameters:

dataSet
Which data set contains the column that has data that has changed.
column
Which column has data that has changed.
value
The new value of the data in the column that changed.