An interface object does not open in the Interface Designer when selected from the Appian Designer. Instead, the “Working…” indicator and the Appian wallpaper is shown. After a short time, the “Working…” indicator will disappear. Refreshing the page with the web browser’s Refresh results in the same behavior.
When trying to swap views from Expression View to Design View while editing an interface object with this issue a pink box error message should display:
The Appian application server log shows the following:
com.appiancorp.process.expression.ExpressionRuntimeException$AppianExceptionProvider: Expression evaluation error : Unmatched close parenthesis ) (APNX-1-4198-000)
The issue can be seen with the following test:
In some circumstances, the SAIL parser in the Interface Designer is unable to detect incorrectly placed commas resulting in this behavior. This has been seen when using some Appian Functions and incorrect comma placement within conditional expressions. The example above demonstrates the issue with incorrect comma placement using the Appian a!save function within the conditional if() function.
This issue has been reported to the Appian product team. The reference number for this issue is AN-74118.
Correct the SAIL syntax by placing the comma after the appropriate ending curly brace rather than before the ending curly brace. Since the Interface Designer will not load the SAIL form to allow you to correct the syntax, the interface object must be exported, modified directly in XML, then re-imported. Steps to perform this include:
This article applies to Appian 7.11 and later.
Last Reviewed: March 2017
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