[Pas2js] External class with custom event

[Michael Van Canneyt]

On Mon, 22 May 2023, Michael Van Canneyt via Pas2js wrote:

>
>
> On Mon, 22 May 2023, Luca Olivetti via Pas2js wrote:
>
>> Hello,
>> 
>> with the help of chatGPT I defined a wrapper for
>> 
>> https://github.com/Choices-js/Choices
>> 
>> now, that class fires a custom event
>> 
>> https://github.com/Choices-js/Choices#events
>> 
>> how can I wrap that?
>> 
>> What I'm doing now is quite cumbersome/inelegant (here I'm trying to get 
>> the value of the selection):
>> 
>> procedure TMyApplication.BindElements;
>> begin
>> theselect:=TJSHTMLSelectElement(document.getElementById('choices-test'));
>> thechoice:=TChoices.new(theselect,new([
>>    'allowHTML', true
>>    ]));
>>  thechoice.setChoices(
>>    [
>>      new(['value','a','label','valor a']),
>>      new(['value','b','label','valor b']),
>>      new(['value','c','label','valor c'])
>>    ],'value','label',true
>>  );
>>  theselect.addEventListener('choice', at ShowSelection);
>> end;
>> 
>> 
>> procedure TMyApplication.ShowSelection(event: TJSEvent);
>> var
>>  detail,choice: TJSObject;
>>  value: JSValue;
>> begin
>>  detail:=TJSObject(event.Properties['detail']);
>>  console.log(detail);
>>  choice:=TJSObject(detail.Properties['choice']);
>>  console.log(choice);
>>  value:=choice.Properties['value'];
>>  console.log(value);
>> end;
>> 
>> 
>> gpt suggestion (that I didn't try because the "external name 'Event'" is 
>> already used for the definition of TJSEvent) is:
>> 
>> type
>>  TEvent = class external name 'Event'
>>  public
>>    property target: TJSObject; external name 'target';
>>    property currentTarget: TJSObject; external name 'currentTarget';
>>    property type_: string; external name 'type';
>>    property detail: TJSObject; external name 'detail';
>>    // Add other properties and methods as needed
>>  end;
>
> You can reuse a external name.
>
> The chatGPT suggestion is not quite correct.
>
> One of the following should do it.
>
> type
>  // read-only properties
>  TMyDetail = class external name 'Event' (TJSObject)

Copy & paste error, this should be
   TMyDetail = class external name 'Object' (TJSObject)

Michael.