How to access native UI components' instance methods in React Native

Question

We can control custom native UI components\' properties by exporting native properties using RCT_EXPORT_VIEW_PROPERTY.

But how to export instance method

Answer 1

I'm not an Objective C expert but a Swift developer.

I better use this way just for readability (maybe there are drawbacks in Obj-C?):

• In Manager: store a reference to your view in an instance private property
• it will then help to call your view's method

Obj-C side - component manager:

@implementation RNAnalogClockManager {
  RNAnalogClock* _AnalogClock;
}

RCT_EXPORT_MODULE()

- (UIView *)view
{
  // keep a reference to the view before returning it
  _AnalogClock = [[RNAnalogClock alloc] init];
  return _AnalogClock;
}

// export method and easily call view method 
RCT_EXPORT_METHOD(startRealTime) {
  [_AnalogClock startRealTime];
};

JS side remains the same

NOTE: I don't need callback in my example but it does not change the principle it is just another parameter.