Fix collection undefined when used with other drag and drop components

[szszoke]

#170
Returning find only when this.active is not undefined fixes the issue.

[clauderic]

Hey @szabolcsx, while this does look like it fixes the issue you ran into, I think the root of the issue must be somewhere else, as getActive() should never be called in the first place if this.active is undefined

[szszoke]

I see. I will investigate further the problem.

[clauderic]

Much appreciated, thank you 🙏

[szszoke]

Hi,

I think I found the cause: the problem appeared when I started to move the cursor. I think the mouse move event was bubbling up, so I just had to do the following to stop that:

<Draggable
    { ...props }
    onDrag={event => event.stopPropagation()} />

[elie222]

stopPropagation doesn't seem to be the best solution with React Draggable as it will stop the drag handle moving. For others looking I recommend using: shouldCancelStart.