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TcxTreeListColumn.OnValidateDrawValue Event

In This Article

Enables you to customize the manner in which validation errors are visualized in the column’s data cells.

#Declaration

Delphi
property OnValidateDrawValue: TcxTreeListValidateDrawValueEvent read; write;

#Remarks

The Sender and ANode parameters identify the column and the node that correspond to the currently processed data cell.

The AValue parameter contains the cell editor‘s edit value. Test the AValue against the same validation logic as you have for the column Properties.OnValidate event handler to determine if this value is valid.

The AData parameter references a TcxEditValidateInfo object to be used to visualize validation errors in the cell editor. For this event, the object properties are initialized with the values that correspond to a valid edit value. If AValue fails validation, you can customize these properties to specify the error icon and error message for the cell editor.

Note that error icons and error messages can be displayed only if the appropriate flags are set within the column Properties.ValidationOptions property.

To see how to tailor the OnValidateDrawValue event, the Properties.ValidationOptions property, and the column Properties.OnValidate event for validating data in cell editors, run the EditorsInPlaceValidationDemo shipped with the ExpressQuantumTreeList Suite.

See Also