Rendering a Chart
After you have initialized your chart, provided the data to plot and set any other desired attributes, you render the chart by calling the .CHART RENDER routine. This requires just one argument, a field to contain the name of the generated graphic file. The routine will then invoke Chart Director, which will create the graphic file. You can also pass a file name, in which case it will create that file in the default chart directory. If you pass a complete path and file name, the chart will be rendered to that location. If you pass a blank field, the API will assign a unique name for you, using the settings in the parameter file.
If you have standard colors or other attributes that should be the same across all charts, you can create your own subroutine that sets all these attributes before calling .CHART RENDER. In your applications, you would call this subroutine instead of calling .CHART RENDER directly. This would give all your charts a common look and feel.
To use the chart in an input or output process, place an alpha field on your image, drag it out to the appropriate size, and set the GUI attributes to PICTURE, Location Type of SERVER, Position to EXPAND PROP'L and check the Transparent flag. You can then pass this field to the .CHART RENDER routine, and Appx will display the completed chart on your image. Make sure the alpha field is long enough to contain the complete path and file name.
The rendered chart file is not automatically removed, it is your responsbility to clean up any chart files that are no longer needed. The End of Process Event point (for both Inputs and Outputs) is a logical choice, if you are only rendering one chart in the process. If you are rendering more than one chart in the process, you will have to use another technique.
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