Snapshot-friendly

[DickSmith]

Changes to allow this plugin to be used with android webpack/snapshot.

Java package/namespaces usage evaluated at build time will cause snapshot to fail so must be placed in a function that will not execute until runtime. Additional typing added via interfaces to compensate for the loss of having the class inside a function.

[PeterStaev]

Hey @DickSmith , can you explain in which cases doe snapshot fail? Because the current demo and demo-ng apps are compiled with snapshot during CI and from what I see there are no problems (https://travis-ci.org/PeterStaev/NativeScript-Drop-Down/jobs/340329407#L3645). So seems there is some specific use case where snapshots are failing and I want to include those in the demo apps so it is properly tested by TravisCI.

Thanks!

[PeterStaev]

You can safely add the package-lock.json to git.

[DickSmith]

Hey @PeterStaev,

So snapshot only takes a snapshot of the vendor bundle (by default), so plugins will only get snapshotted if you add import 'nativescript-drop-down' (TS-style) or require('nativescript-drop-down') (JS-style) to app/vendor.ts.

So in looking at the vendor.ts for both demo and demo-ng it looks like the plugin isn't actually being snapshotted. If you add the plugin there (without my changes) you should see it fail snapshot complaining about ReferenceError: android is not defined or for java depending on which packages are being used. Otherwise nativescript-drop-down doesn't get included in the snapshot, which it ideally is if used in multiple modules (like I do in my form-heavy app :D ).

I had to fork and make similar changes for ~8 plugins to be able to make snapshot work with my current vendor.ts imports. Totally worth it, though, as I shaved ~50% off my boot times (from about ~6 seconds down to ~4 seconds on my own LG G6, with similar ratios on even slower devices).

For reference I made a similar PR to nativescript-background-http.

I've added now added the package-lock.json to the repo with my latest commit and also added require("nativescript-drop-down") to demo-ng (for PAN apps I'm not sure if it should be added before, after, or in-between .vendor-platform and bundle-entry-points so you'd have to find out what the best practice is there).

[PeterStaev]

Very interesting! I might have to look at my apps and add some of the plugins to the vendor chunk 😉 Thanks for your work!