Update to include action buttons on android

[pinkfish]

Redid the structure a bit to make it easier to include. Plus added action button support on Android.

[MaikuB]

First off all, thanks a lot for submitting a PR. It's good to see other members of the community trying to contribute. Unfortunately, I think I'll have to turn down your changes as both of your changes are things I had already started looking into. Originally I didn't move the Dart classes into lib/src, thinking in future there could be ambiguity if there were platforms with the same class names and the namespaces could be used to solve that issue.

With regards to see notification actions, if you looked at the issues board then you can see I'm already tracking this in #17 and that I'm waiting to see if members of the Flutter team can provide more information. Your changes only covers the scenario where actions launch an app but the actions should also be able to execute Dart code without having the app running. My testing shows that this is possible but it would seem like the APIs exposed by Flutter on Android are missing the capability to pass the payload back. Thus, I'm waiting to see if there the APIs will be changed to support this

[MaikuB]

Hey @pinkfish, not sure where else to ask so I thought I'd comment here. Wanted to check with you on an issue (#88) that other devs experienced I noticed you had a change on your fork around checking if the notification id is an int or long so am wondering if it's because you had the same problem. I haven't run into the same problem with the values they had used though but perhaps I'm missing something.

[pinkfish]

Yes, I ran into that same problem. Not sure why it is in an int vs a long, but I get the error at times when it does a callback. The fix works :)

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On Mon, 13 Aug 2018 at 21:23, Michael Bui ***@***.***> wrote: Hey @pinkfish <https://github.com/pinkfish>, not sure where else to ask so I thought I'd comment here. Wanted to check with you on an issue (#88 <#88>) that other devs experienced I noticed you had a change on your fork around checking if the notification id is an int or long so am wondering if it's because you had the same problem. I haven't run into the same problem with the values they had used though but perhaps I'm missing something. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#38 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ACbmMUjgzYrdSaBwZd4GP0Ybivv2Auztks5uQlCygaJpZM4UF0Ix> .

[MaikuB]

Thanks for getting back to me :)
Actually I think your case might be bit different, I'd imagine your using numbers that requires more than 32 bits, a Dart int will become a Long on the Android side. The values used in the aforementioned issue should fit within an int