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1. Value help 默认加载行为

(1). CDS annotation

@Consumption.valueHelpDefault.fetchValues

Possible Values:
#AUTOMATICALLY_WHEN_DISPLAYED (default in OData V4)，自动加载，当你打开value help dialog时，请求已经触发。
#ON_EXPLICIT_REQUEST (default in OData V2)，手动加载，需要在value help dialog上点击GO button触发请求。

(2). XML annotation

XML annotation for loading behavior of Value Helps

FetchValues = 1: Show values in the result table of the Value Help Dialog immediatelly when opening the dialog.
FetchValues = 2: Show values in the result table of the Value Help Dialog only on request, i.e. only after pressing Go in the Value Help Dialog.
If the property is not provided then the default applies as defined by UX (data are loaded immediately).

2. Definition of context dependent Value Helps

It is possible to offer for a field different value helps: the value helps which are shown depend on the context of other fields.

Example: A sales order has different type of partners which can be assigned to it. Depending on the partner function different details have to be offered in the value help in which the partner can be added.

For a customer a customer specific value help is needed
For a personnel a person specific value help is needed
The context dependent value helps can be achieved by providing the annotation Common.ValueListRelevantQualifiers.
Technical example:

(1). XML annotation

XML annotation for context dependent Value Helps

3. Definition of a smaller number of fields for Type Ahead

设置type ahead list中显示的字段

(1). CDS annotation

@UI.lineItem.importance: #HIGH

(2). XML annotation

XML annotation for field importance

Columns which are not annotated with the UI.Importance High will not be shown in the Type Ahead window.

Please note: all search enabled fields of a value help have to be shown as columns in type ahead result list, i.e. searchable fields must never be hidden for the type ahead suggestion list.

4. Hidden Fields in the Filter Area

Filter area 是value help dialog上显示filter的区域

The value help dialog displays various filter fields. Usually the filter fields are identical with the columns of the result table. It is, however, possible to reduce the number of filter fields without removing the corresponsing columns from the result table: this can be achieved by the annotation UI.HiddenFilter. If fields shall be completely removed as filters fields and as columns in the result list then one can achieve this either by removing them from the parameters collection of the ValueHelp annotation or by annotating them with UI.Hidden.

(1). XML annotation

XML annotation for Hidden Fields in the Filter Area