Addresses #80.
Caveat: I am not an Android developer. This code comes from a fork of the original RN WebView that we have been using in production for some time, so all credit goes to @Oblongmana: https://github.com/Oblongmana/react-native-webview-file-upload-android.
Setting up a DownloadManager for the WebView is pretty straightforward, as is adding any known cookies to the request. Most of the complication comes from the requirement after SDK 23 to ask the user for the WRITE_EXTERNAL_STORAGE permission. Unfortunately there is no mechanism to suspend the download request until permission is resolved so this code stores off the request and sets up a listener that enqueues the download once permissions are resolved so the user experience is really nice.
I didn't see anything in the way of tests or documentation that needs to be added for this change, so let me know if I missed anything. Thanks!
In the current code using `startInLoadingState` and `injectedJavaScript` will result in an infinite loading state if `injectedJavaScript` fails to evaluate for some reason. This adds a red box error explaining there was a failure to evaluate javascript. In my case this was do to the JS string not returning a valid type so I've added a that as a potential solution in the error message and added some documentation to the API Reference with some additional warnings.
To reproduce the existing behavior setup a webview with `startInLoadingState` and `injectedJavaScript` that returns an invalid type (in my case it returned a function). You should see an infinite loading state as `onLoadEnd` is never called.
Try the same with this branch and you'll get a nice red box error suggesting one potential solution to the problem.
Fixes#33
I could really use some help from an Android developer on this one, because I just "made it work", don't know how to "make it work good".
Some things that should be reviewed:
- [ ] validate Android 5.0 devices (my emulator work, but outputs some weird sounds; a Galaxy 4 I tested on crashes)
- [ ] validate Android 5.1 devices (emulator works, couldn't find a real device)
- [ ] how to handle File Extensions? (https://www.w3schools.com/tags/att_input_accept.asp)
I'm sure that there's more refactoring to be done, so any help and advice would be appreciated.
Roy Zheng
