LiveCycle Designer ES lets you preview and test your form by using sample XML data. It is recommended that you frequently test your form with sample data to ensure that the form renders correctly. If you do not have sample data, LiveCycle Designer ES can create it, or you can create it yourself. (See To automatically generate sample data to preview your form and To create sample data to preview your form.)
Testing your form by using a sample data source ensures that the data and fields are mapped and that repeating subforms repeat as you expected. You can create a balanced form layout that provides the appropriate space for each object to display the merged data.
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To preview a form using sample data