Allowing the user to select output options

Users can choose the format to see the report output.

In the GRW demo program Order Report, this form allows the user to make choices regarding the output:

This figure is a screenshot of the Report demo form. — Figure: Report demo Form

This code implements this functionality. The form definition file, Configuration.4fd, is included in the demo files for Reports, the GRW Demo.

The MAIN block of SimpleReport.4gl would change as follows:

Call a function named select_output that displays the form and returns the user's choices
Configure the report using the mandatory Reporting API functions plus these additional functions:
- fgl_report_selectDevice - sets the report output; the parameter is one of: "Printer", "PDF", "Image", "SVG" .
- fgl_report_selectPreview - sets the preview option; the parameter is TRUE (preview) or FALSE (no preview).

 MAIN

   DEFINE handler om.SaxDocumentHandler, -- report handler 
          data_file String,              -- XML file containing data 
          report_ok boolean,             -- return value from function 
          r_filename STRING,             -- filename of desired report   
          r_output  STRING,              -- output format 
          preview INTEGER                -- preview indicator 

   -- call the mandatory functions that configure the report using the
     -- choices made by the user 
   -- in your new select_output function
   CALL select_output() RETURNING r_filename, r_output, preview 
   IF fgl_report_loadCurrentSettings(r_filename) THEN  -- if the file loaded OK
     CALL fgl_report_selectDevice(r_output)            -- changing default
     CALL fgl_report_selectPreview(preview)            -- changing default
     LET handler = fgl_report_commitCurrentSettings()  -- commit changes
   ELSE 
     EXIT PROGRAM
  END IF

   -- run the report by calling the report driver contained in
   --  your function runReportFromDatabase
   IF handler IS NOT NULL THEN  
     CALL runReportFromDatabase()
   END IF

 END MAIN

select_output - this new function displays a form allowing the user to specify the name of the report to be run (the name of the 4rp file), the output format, and whether a preview is preferred.

 FUNCTION select_output()
    DEFINE
      r_output   STRING,   -- output format option
      r_action   STRING,   -- used to set preview option
      r_filename STRING,   -- filename of Report Design document (4rp filename)
      preview    INTEGER   -- preview option TRUE/FALSE, to display 
                             -- report in Report Viewer
  
   CLOSE WINDOW SCREEN
   OPTIONS INPUT WRAP 
    -- display form allowing  user to select the 4rp filename and output options 
   OPEN WINDOW f_configuration WITH FORM "Configuration"
   LET INT_FLAG=FALSE
   LET preview = FALSE
   INPUT BY NAME r_filename,r_output,r_action 
     ON ACTION CANCEL
       EXIT PROGRAM
     ON ACTION CLOSE
       EXIT PROGRAM
   END INPUT
   CLOSE WINDOW f_configuration 
   CALL ui.interface.refresh()        

   -- set preview variable to match output option r_action
   IF r_action IS NOT NULL THEN
     IF r_action == "preview" THEN
      LET preview = TRUE
     END IF
   END IF

   -- return report name (filename of Report Design Document) and output
     -- option variables to be used to configure the report engine
   RETURN r_filename||"4rp", r_output, preview 

 END FUNCTION