How can i get and pass the user input from one fragment to another fragment with only one mainactivity

Question

I just start to learn how to use Android studio for a while and my teacher asks me the question above with many require. But I don't even get the concept to get and pass the data. Hope someone can tell me the concept with some coding.

Answer 1

In case both fragments display on activity, you should use viewmodel, this is link for more infor and has code sample pass data via viewModel document . With other cases, you can use bundle to transfer data.

Answer 2

You can choose FragmentResult API or viewModel. It depends on the nature of the data you want to pass. If it is just a simple "result", like your fragment A want to know you click which button in fragment B, the FragmentResult is enough. If you need to share data between A and B, viewModel is better.

FragmentResult:

fragment A

setFragmentResultListener("requestKey") { requestKey, bundle ->
    // We use a String here, but any type that can be put in a Bundle is supported
    val result = bundle.getString("bundleKey")
    // Do something with the result
}

fragment B

button.setOnClickListener {
    val result = "result"
    // Use the Kotlin extension in the fragment-ktx artifact
    setFragmentResult("requestKey", bundleOf("bundleKey" to result))
}

Here is the doc