59.3 Returning Data from an Activity

As the example in the previous section stands, while data is transferred to ActivityB, there is no way for data to be returned to the first activity (which we will call ActivityA). This can, however, be achieved by launching ActivityB as a sub-activity of ActivityA. An activity is started as a sub-activity by creating an ActivityResultLauncher instance. An ActivityResultLauncher instance is created by a call to the registerForActivityResult() method and is passed a callback handler in the form of a lambda. This handler will be called and passed return data when the sub-activity returns. Once an ActivityResultLauncher instance has been created, it can be called with an intent parameter to launch the sub-activity. The code to create an ActivityResultLauncher instance typically reads as follows:

val startForResult = registerForActivityResult(

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