IDLitParameter::OnDataChangeUpdate

Syntax | Arguments | Keywords | Example | Version History

The IDLitParameter::OnDataChangeUpdate method is called when a data value has been updated or a new data object has been associated with the visualization object.

Note
A visualization class based on the IDLitVisualization class must implement this method in order for changes or additions to the data parameters to be updated automatically in the resulting visualizations.

Syntax

Obj->[IDLitParameter::]OnDataChangeUpdate, Data, ParameterName

Arguments

Data

An object reference to the IDLitData object or the IDLitParameterSet object containing the changed parameter data. If Data is an IDLitParameterSet object, the ParameterName argument must be set to the string '<PARAMETER SET>'.

ParameterName

An upper-case scalar string containing the name of the parameter that has changed. The parameter specified via this argument must be registered with the visualization object. If oData is an IDLitParameterSet object, this argument must be set to the string '<PARAMETER SET>'.

Keywords

None

Example

Normally, an implementation of this method will contain a CASE statement that switches based on the value of the ParameterName argument. For example, the following code handles a parameter named Z:

PRO MyVis::OnDataChangeUpdate, oData, ParameterName 
 
CASE ParameterName OF 
   'Z': BEGIN 
      ;; do something with the z data 
   END 
   '<PARAMETER SET>': BEGIN 
      oZ = oData->GetByName('Z') 
      ;; do something with the z data. 
   END 
ENDCASE 
 
END 


Note

The Z parameter is handled twice — once if supplied as an individual IDLitData object and once if supplied via the IDLitParameterSet object.

See Creating an OnDataChangeUpdate Method in the section Creating a New Visualization Type (iTool Developer's Guide) for more discussion of the OnDataChangeUpdate method.

Version History