Building a window

One other object you need when piping data in your application
is a window. You use this window to provide a user interface to
the pipeline, enabling people to interact with it in one or more
ways. These include:

Starting the
pipeline’s execution
Displaying and repairing any
errors that occur
Canceling the pipeline’s
execution if necessary

Required features for your window

When you build your window, you must include a DataWindow
control that the pipeline itself can use to display error rows (that
is, rows it cannot pipe to the destination table for some reason).
You do not have to associate a DataWindow object with this DataWindow
control—the pipeline provides one of its own at runtime.

To learn how to work with this DataWindow
control in your application, see “Starting the pipeline “ and “Handling row errors “.

Optional features for your window

Other than including the required DataWindow control, you
can design the window as you like. You will typically want to include
various other controls, such as:

CommandButton or PictureButton controls to
let the user initiate actions (such as starting, repairing, or canceling
the pipeline)
StaticText controls to display
pipeline status information
Additional DataWindow controls to
display the contents of the source and/or destination tables

If you need assistance with building a window,
see the PowerBuilder Users Guide.

Example

The following window handles the user-interface aspect of
the data piping in the order entry application. This window is named w_sales_extract:

Several of the controls in this window are used to implement
particular pipeline-related capabilities. Table 17-2 provides more information
about them.

Table 17-2: Window controls to implement
pipeline capabilities
Control type	Control name	Purpose
RadioButton	rb_create	Selects pipe_sales_extract1 as the Pipeline object to execute
RadioButton	rb_insert	Selects pipe_sales_extract2 as the Pipeline object to execute
CommandButton	cb_write	Starts execution of the selected pipeline
	cb_stop	Cancels pipeline execution or applying of row repairs
	cb_applyfixes	Applies row repairs made by the user (in the dw_pipe_errors DataWindow control) to the destination table
	cb_forgofixes	Clears all error rows from the dw_pipe_errors DataWindow control (for use when the user decides not to make repairs)
DataWindow	dw_review_extract	Displays the current contents of the destination table (Quarterly_extract)
DataWindow	dw_pipe_errors	(Required) Used by the pipeline itself to automatically display the PowerBuilder pipeline-error DataWindow (which lists rows that cannot be piped due to some error)
StaticText	st_status_read	Displays the count of rows that the pipeline reads from the source tables
	st_status_written	Displays the count of rows that the pipeline writes to the destination table or places in dw_pipe_errors
	st_status_error	Displays the count of rows that the pipeline places in dw_pipe_errors (because they are in error)

Document get from Powerbuilder help

Thank you for watching.

Powerbuilder Documentation 12.5

August 9, 2023

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