Interface AttributeValuesEnumeratorInterface

The AttributeValuesEnumeratorInterface is used to query available values of a string attribute (AttributeInfoInterface).

The AttributeValuesEnumeratorInterface is created from a connected DataSessionInterface by the use of the DataSessionInterface.createAttributeValuesEnumerator function.

/** 
 * Sample to illustrate the use of an AttributeValuesEnumeratorInterface.
 * The AttributeValuesEnumeratorInterface is used to query available values of a string attribute.
 */
import {
    AttributesDictionaryInterface, AttributeInfoInterface, AttributeType, DataSessionInterface,
    AttributeValuesEnumeratorInterface, AttributeValuesEnumeratorInterfaceSignal,
} from 'generated_files/documentation/appinfiniteapi';

// the DataSessionInterface has been created previously and is connected
let lDataSession : DataSessionInterface;

// the attribute name to query
const lAttributeNameToQuery : string = 'CompletionStatus';
// MAKE SURE the attributes "CompletionStatus" is relevant
const lAttributeDictionary : AttributesDictionaryInterface = lDataSession.getAttributesDictionary();
const lAttributeInfo : AttributeInfoInterface | undefined = lAttributeDictionary.getAttributeInfo(lAttributeNameToQuery);
// make sure the attribute is a string one
console.assert((lAttributeInfo !== undefined) && (lAttributeInfo.getAttributeType() === AttributeType.ATTR_STRING));
// the expected values
const lAvailableValues : Array<string> = [];
// using an attribute value enumerator to query available values
const lAttributeValueEnumerator : AttributeValuesEnumeratorInterface = lDataSession.createAttributeValuesEnumerator();

// we may have queried only values that strictly begin with a fixed pattern
// but here we want to query all values => use an empty string
// WARNING : the enumeration is case sensitive !!!
const lAttributeInitResult : boolean = lAttributeValueEnumerator.initEnumeration(lAttributeNameToQuery, '');
// make sure the enumeration has started
console.assert(lAttributeInitResult);

// make sure we are ready to get the result
lAttributeValueEnumerator.addEventListener(AttributeValuesEnumeratorInterfaceSignal.AttributesEnumerationReady, () : void => {
    // make sure everything went well
    if(lAttributeValueEnumerator.getLastError() !== undefined)
    {
        console.log('Enumeration request failed');
        return;
    }
    // retrieve the enumeration result
    const lValues : Array<string> = lAttributeValueEnumerator.getEnumerationResult();
    // push the result to our array
    lAvailableValues.push(...lValues);
    // and if further values can be queries, go on !
    if(lAttributeValueEnumerator.hasOtherValues())
    {
        lAttributeValueEnumerator.nextValues();
    }
    else
    {
        // we have done it !
        // display the available values
        console.log(lAvailableValues);
        // perhaps here some GUI code ?
    }
});

// and start the enumeration !
lAttributeValueEnumerator.nextValues();

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or asynchronously :

/** 
 * Sample to illustrate the asynchronous use of an AttributeValuesEnumeratorInterface.
 * The AttributeValuesEnumeratorInterface is used to query available values of a string attribute.
 */
import {
    AttributesDictionaryInterface, AttributeInfoInterface, AttributeType, DataSessionInterface,
    AttributeValuesEnumeratorInterface, AsyncAttributeEnumerationResult,
} from 'generated_files/documentation/appinfiniteapi';

// the DataSessionInterface has been created previously and is connected
let lDataSession : DataSessionInterface;

// the attribute name to query
const lAttributeNameToQuery : string = 'CompletionStatus';
// MAKE SURE the attributes "CompletionStatus" is relevant
const lAttributeDictionary : AttributesDictionaryInterface = lDataSession.getAttributesDictionary();
const lAttributeInfo : AttributeInfoInterface | undefined = lAttributeDictionary.getAttributeInfo(lAttributeNameToQuery);
// make sure the attribute is a string one
console.assert((lAttributeInfo !== undefined) && (lAttributeInfo.getAttributeType() === AttributeType.ATTR_STRING));
// the expected values
const lAvailableValues : Array<string> = [];
// using an attribute value enumerator to query available values
const lAttributeValueEnumerator : AttributeValuesEnumeratorInterface = lDataSession.createAttributeValuesEnumerator();

// we may have queried only values that strictly begin with a fixed pattern
// but here we want to query all values => use an empty string
// WARNING : the enumeration is case sensitive !!!
const lAttributeInitResult : boolean = lAttributeValueEnumerator.initEnumeration(lAttributeNameToQuery, '');
// make sure the enumeration has started
console.assert(lAttributeInitResult);

const fetchValues = async () : Promise<void> => {
    // loop till no other values are available
    let lHasAvailableValues : boolean = true;
    let lRequestResult : AsyncAttributeEnumerationResult;
    while (lHasAvailableValues)
    {
        lRequestResult = await lAttributeValueEnumerator.asyncNextValues();
        // make sure we are ready to get the result
        // make sure everything went well
        if(lRequestResult.error !== undefined || lRequestResult.value === undefined)
        {
            console.log('Enumeration request failed');
            return;
        }
        // retrieve the enumeration result
        const lValues : Array<string> = lRequestResult.value;
        // push the result to our array
        lAvailableValues.push(...lValues);
        // and if further values can be queries, go on !
        lHasAvailableValues = lAttributeValueEnumerator.hasOtherValues();
    }
    // we have done it !
    // display the available values
    console.log(lAvailableValues);
    // perhaps here some GUI code ?
};
fetchValues();

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The AttributeValuesEnumeratorInterface must be used to fully handle FilterAttributeInterface.

See

AttributeValuesEnumeratorInterfaceSignal