This function defines a specific step within a workflow.
Note: When users finish or close a workflow dialog, the actual workflow object and all the workflow step objects it contains will be destroyed.
Example
See the example for ENVIWorkflow and other examples in the Creating Workflows topic.
Syntax
Result = ENVIWorkflowStep([Properties=value], ERROR=value)
Return Value
This routine returns a reference to an ENVIWorkflowStep object.
Methods
GetUIObject
StyleSheetHideParameters
StyleSheetResetUIClass
StyleSheetSetUIClass
StyleSheetShowParameters
Arguments
None
Properties
CALLBACK_APPLY_STYLESHEET (Get, Set)
Set this property to a string with the name an ENVI procedure that will be invoked before a stylesheet is applied to the task. See Callback Example: Show and Hide Task Parameters to learn more.
CALLBACK_EXECUTE (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked when the task is executed. This is used only when defining a custom task workflow step.
CALLBACK_POSTBUILDUI (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked immediately after the workflow step dialog is created. See Callbacks to learn more.
CALLBACK_POSTEXECUTE (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked immediately after the task is executed. See Callbacks to learn more.
Tip: If you add a DISPLAY_RESULT=displayResult keyword to your post-execute callback routine, the CALLBACK_POSTEXECUTE property will return the value that you specified for SHOW_DISPLAY_RESULT.
CALLBACK_PREBUILDUI (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked immediately before the workflow step dialog is created. See Callbacks to learn more.
CALLBACK_PREDESTROYUI (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked immediately before the workflow step dialog is destroyed. See Callbacks to learn more.
CALLBACK_PREEXECUTE (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked immediately before the task is executed. See Callbacks to learn more.
CALLBACK_SKIP_STEP (Get, Set)
Set this property to a string with the name of an ENVI procedure that will be invoked when a workflow step dialog is displayed, allowing a user to optionally skip the step.
DESCRIPTION (Get, Set)
Specify a string with a description of the workflow step.
NAME (Get, Set)
Specify a string with a custom name for the step. Naming individual steps is helpful when you need to access them via callbacks within a workflow.
SHOW_DISPLAY_RESULT (Get, Set)
This property controls the Display result option in workflow steps. The default value is -1, which means this option is hidden in every workflow step except the last one. You can override this behavior by setting SHOW_DISPLAY_RESULT to 1 in any step where you want to expose the Display result option. To hide this option in the last step, set SHOW_DISPLAY_RESULT to 0 in the final step of your workflow.
SHOW_PREVIEW (Get, Set)
This property controls the Preview option in workflow steps. The default value is -1, which means ENVI will determine if the task can be previewed (normally available when the task has both input and output raster parameters). You can override this behavior by setting SHOW_PREVIEW to 1 in any step where you want to expose the Preview option. To hide this option, set SHOW_PREVIEW to 0.
SUBTITLE (Get, Set)
Set this property to a string with a subtitle to display in the workflow step. See Customize the Visual Appearance of Workflow Dialogs to learn more.
TASK (Get, Set)
Specify the task to run in the step by invoking the ENVITask function with a valid task name; for example:
step1.TASK = ENVITask('QUAC')
TIMELINE_TITLE (Get, Set)
Set this property to a string with the timeline title to display in the workflow step. See Customize the Visual Appearance of Workflow Dialogs to learn more.
TITLE (Get, Set)
Set this property to a string with the main title to display in the workflow step. See Customize the Visual Appearance of Workflow Dialogs to learn more.
Keywords
ERROR
Set this keyword to a named variable that will contain any error message issued during execution of this routine. If no error occurs, the ERROR variable will be set to a null string (''). If an error occurs and the routine is a function, then the function result will be undefined.
When this keyword is not set and an error occurs, ENVI returns to the caller and execution halts. In this case, the error message is contained within !ERROR_STATE and can be caught using IDL's CATCH routine. See IDL Help for more information on !ERROR_STATE and CATCH.
See Manage Errors for more information on error handling in ENVI programming.
Workflow dialogs are not modal, which means that after the first step displays, further errors will not be captured by this keyword.
Version History
API Version
4.2
See Also
ENVIWorkflow, ENVIDataContainer