Visible and Invisible Operation Parameters

Understand the differences between client-visible and invisible operation parameters, and how to make an operation parameter invisible to the client.

You can hide client-visible object parameters using the Device Application Designer. That is, you can configure the device application so the operation parameter is not visible to the device application user. But the parameter itself is still visible in the object API.

Client-visible operation parameters – the client application can change the value of the parameter (a parameter of an MBO Create, Update, or Delete operation that is client-visible) and pass the value through the client object API.
Non-client-visible operation parameters – if a parameter is not client-visible, the client application cannot see or directly pass a value for the parameter. Client-invisible parameters can be either:
1. No parameter at all – delete the operation parameter from Unwired WorkSpace, in which case the personalization key column is disabled and the constant value is passed at runtime. Or
2. Fill-from-attribute parameters – the API consumer operates on attributes that have no create() operation parameters. For example:
```
cust.setName('Jones');
cust.setAddress("1 sybase dr.");
cust.create();
```
Structured parameters – If a structure-typed parameter has all its fields mapped to client-invisible bindings, a corresponding parameter element is not generated and therefore not available through the client object API. Client visibility of a structured parameter is determined by the visibility of its children: if all children of a structured parameter are not client-visible, then the structure parameter is not client-visible. If any one of the parameters is client-visible then the parent structured parameter is client-visible. This rule applies recursively in cases of nested structured parameters.
If all the subnode values in the nested structure are null, an empty structure type instance is created instead of null, for the flattened structure parameter.
Visibility of client parameters that use personalization key and constant values – By default, Read, Create, Update, or Delete operation parameters that are not fill-from-attribute parameters are client-visible (that is, operation parameters are visible when developing a device application in the Device Application Designer). To hide these parameters from the device application user:
1. From the Device Application Designer Screen Designer, select Edit operation action on the Submit button to open the Operation Action dialog.
2. Double-click the operation parameter to configure the parameter's source.
3. From the Operation Action screen, you can assign the parameter value from personalization key, literal, variable, or Null value. If you assign Null to a Create, Update, or Delete operation parameter, or personalization key value, then constant values are checked for at runtime. This does not apply to Read operations.