In addition to implementing the RCTBridgeModule protocol, your class must also include the RCT_EXPORT_MODULE() macro. This takes an optional argument that specifies the name that the module will be accessible as in your JavaScript code (more on this later). If you do not specify a name, the JavaScript module name will match the Objective-C class name.
React Native will not expose any methods of CalendarManager to JavaScript unless explicitly told to. This is done using the RCT_EXPORT_METHOD() macro:
RCTResponseSenderBlock accepts only one argument - an array of parameters to pass to the JavaScript callback. In this case we use node's convention to make the first parameter an error object (usually null when there is no error) and the rest are the results of the function.
RCTResponseSenderBlock accepts only one argument - an array of parameters to pass to the JavaScript callback. In this case we use Node's convention to make the first parameter an error object (usually null when there is no error) and the rest are the results of the function.
A native module is supposed to invoke its callback only once. It can, however, store the callback and invoke it later. This pattern is often used to wrap iOS APIs that require delegates. See RCTAlertManager for an example.
If you want to pass error-like objects to JavaScript, use RCTMakeError from RCTUtils.h. Right now this just passes an Error-shaped dictionary to JavaScript, but we would like to automatically generate real JavaScript Error objects in the future.
Native modules can also fulfill a promise, which can simplify your code, especially when using ES2016's async/await syntax. When the last parameters of a bridged native method are an RCTPromiseResolveBlock and RCTPromiseRejectBlock, its corresponding JS method will return a JS Promise object.
Refactoring the above code to use a promise instead of callbacks looks like this:
A native module should invoke its callback exactly once. It's okay to store the callback and invoke it later. This pattern is often used to wrap iOS APIs that require delegates - see RCTAlertManager for an example. If the callback is never invoked, some memory is leaked. If both onSuccess and onFail callbacks are passed, you should only invoke one of them.
If you want to pass error-like objects to JavaScript, use RCTMakeError from RCTUtils.h. Right now this just passes an Error-shaped dictionary to JavaScript, but we would like to automatically generate real JavaScript Error objects in the future.
Native modules can also fulfill a promise, which can simplify your code, especially when using ES2016's async/await syntax. When the last parameters of a bridged native method are an RCTPromiseResolveBlock and RCTPromiseRejectBlock, its corresponding JS method will return a JS Promise object.
Refactoring the above code to use a promise instead of callbacks looks like this: