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IDLitDataOperation::DoExecuteUI

Syntax | Return Value | Arguments | Keywords | Example | Version History

The IDLitDataOperation::DoExecuteUI function method provides a way for the iTool developer to request user input before performing an operation. If the SHOW_EXECUTION_UI property is set, this method will be called before the operation's Execute method is called.


Note
Every operation based directly on the IDLitDataOperation class that requires user interaction before execution must implement its own DoExecuteUI method. See Creating an Operation for details.

The DoExecuteUI method itself can present any interface. In practice, most iTool DoExecuteUI methods use the IDLitTool::DoUIService method to display a user interface requesting user input. User interfaces and UI Services are discussed in iTool User Interface Architecture.


Warning
If the DoExecuteUI method does not return success, the Execute method will not be called.

Syntax

Result = Obj->[IDLitDataOperation::]DoExecuteUI()

Return Value

Returns a 1 if the displayed user interface code executed successfully, and the operation should be executed. If user interface code does not execute successfully, or if the user cancels the operation, this function returns a 0.

Arguments

None

Keywords

None

Example

The following is an example of a DoExecuteUI method, taken from the iTools "Scale Factor" operation: 

FUNCTION IDLitopScalefactor::DoExecuteUI  
  
oTool = self->GetTool()  
IF (oTool EQ OBJ_NEW()) THEN RETURN, 0  
  
RETURN, oTool->DoUIService('ScaleFactor', self)  
  
END

This implementation of the DoExecuteUI method does the following:

  1. Retrieves an object reference to the current iTool using the GetTool method.

    2.  

  2. Checks to make sure the returned object reference is not a null object (which would be the case if the GetTool method failed).

    3.  

  3. Calls the ScaleFactor UI Service.

Version History

6.0
Introduced

  IDL Online Help (March 06, 2007)