make dragndrop example work for a class not an ID.

[laurencefass]

I'm trying to adapt the drag and drop to work for a class of divs not just an ID.
https://github.com/Reactive-Extensions/RxJS/blob/master/examples/dragndrop/dragndrop.html

simple changes to give the div a class nor an ID dont work and i lose ability to drag the element

3 simple changes:

HTML line 7 i.e.

Drag Me!

CSS line 1 i.e. .dragTarget { style attributes unchanged }
JS line 4 i.e var dragTarget = document.getElementsByClassName('dragTarget');

Im not skilled enough to know if this is a bug in RXJS or that the example is not generalised enough. The documentation on events suggests these changes should be sufficient.

[paulpdaniels]

My first guess would be that the events 'mouseup' and 'mousedown' are not supported on an HTMLCollection, which is what getElementsByClassName() returns. You probably have to apply the observable to each item in the collection.

[laurencefass]

theres an example here: https://github.com/Reactive-Extensions/RxJS/blob/master/doc/gettingstarted/events.md. suggests maybe it should work:

var result = document.getElementById('result');
var sources = document.querySelectorAll('div');

var source = Rx.Observable.fromEvent(sources, 'click');

var subscription = source.subscribe(function (e) {
result.innerHTML = e.clientX + ', ' + e.clientY;
});

[mattpodwysocki]

@laurencefass this was an easy fix as getElementsByClassName and getElementsByTagName return an HTMLCollection so we can detect this via Object.prototype.toString.call(el) === '[object HTMLCollection]';.

[laurencefass]

thanks matt, when you say 'easy fix' do you mean you have fixed Rx core and that thegetElementsByClassName example will now just work?