What factors can influence the retention of the View user interface state?

The retention of the user interface View state in Android depends on several factors:

• Activity/Fragment lifecycle: when an Activity or Fragment is recreated (for example, during screen rotation), the View state may be lost if it is not saved and restored.
• State saving methods: methods onSaveInstanceState(Bundle) and onRestoreInstanceState(Bundle) allow saving and restoring the View state.
• View identifiers: for automatic View state saving, they must have a unique identifier (android:id), otherwise the state will not be saved.
• View types: some standard Views (like EditText) automatically save their state, while custom Views require implementing state saving methods.
• External changes: changes in data that the UI is based on can affect the View state.

Example of saving EditText state:

override fun onSaveInstanceState(outState: Bundle) {
    super.onSaveInstanceState(outState)
    outState.putString("input_text", editText.text.toString())
}

override fun onRestoreInstanceState(savedInstanceState: Bundle) {
    super.onRestoreInstanceState(savedInstanceState)
    val text = savedInstanceState.getString("input_text")
    editText.setText(text)
}