Manually bind PickerAndroid instance methods

[dzautner]

In the current version of react-native, the Picker component would some times fail on Android due undefined context (this === undefined) in the methods that are defined using the experimental class property syntax.

As this is experimental syntax which seems to be unreliable in its current form and usage, I suggest to manually bind these methods in the component's constructor.

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@dzautner updated the pull request - view changes

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@dzautner updated the pull request - view changes

[mkonicek]

As this is experimental syntax which seems to be unreliable in its current form and usage, I suggest to manually bind these methods in the component's constructor.

We're using this syntax a lot and it should be reliable thanks to Babel. It looks like the code is equivalent actually. Can you consistently reproduce the bug with this being undefined? When does it happen? Does the bug go away with your change?

[dzautner]

@mkonicek, sorry for not providing enough information.

Yes, we can consistently reproduce the issue with this specific component. We actually use this exact code to resolve the issue temporarily until it is resolved upstream.

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@dzautner updated the pull request - view changes

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@dzautner updated the pull request - view changes

[sophiebits]

Can you please determine why the current code is breaking?

[dzautner]

I'll try to run some tests and narrow it down to the exact cause of the issue.

[dzautner]

@spicyj:

I narrowed the issue down to an issue with babel the is already acknowledged. When using babel with passPerPreset the class property syntax will not be bound to the wrong context.

babel/babel#4230
babel/babel#4337

[sophiebits]

Yeah, that's unfortunate. If you have transform-class-properties in the plugins section then it will work.

[dzautner]

👍 thanks!