fix multiple items ios

[RZulfikri]

Hi, I'm trying to fix this issue #77 based on the code I check it will return the first item using a callback. In my case, I'm trying to share multiple messages (text) from WhatsApp but I always get one message only.

so in this code, I add a code to wait until all item provider finishes and pass to the callback. so it might have changes on return data()

before:

{data: "", mimetype: ""}

now:

[{data: "", mimetype: ""}]

hope it helps, thank you.

[vstoyanoff]

@RZulfikri I have a PR opened that fixes this - #119

[flogy]

If you need this feature right now, check this: #158