ActivityResultContract

ActivityResultContract is a class in the Android Jetpack library that provides a standardized way to handle activity results. It abstracts away the complexities of starting an activity for a result and receiving that result back, offering a cleaner and more robust solution compared to the traditional `startActivityForResult` and `onActivityResult` methods.

The core idea behind ActivityResultContract is to define a contract between the caller and the called activity. This contract specifies the input type required to launch the activity and the output type that will be returned. This clearly defines the expected data flow and improves code readability.

A typical implementation involves creating a class that extends `ActivityResultContract`. This class has two main methods: `createIntent` to construct the intent for the activity to be launched, and `parseResult` to parse the data returned from that activity into the desired output type.

To use an ActivityResultContract, you first register a callback with the `ActivityResultRegistry`. This is typically done using `registerForActivityResult`. You provide an instance of your contract and a callback that will be executed when the result is received. The callback receives the parsed result from the contract.

When you want to launch the activity, you call the `launch` method on the registered activity result launcher, passing in the input data required by your contract. The system then handles starting the activity and delivering the result back to your registered callback. This pattern simplifies handling permissions requests, launching activities for photos, and many other scenarios where you need to get data back from another activity.