// Find the TextView in the layout TextView textView = findViewById(R.id.my_text_view); // Add a TextWatcher to listen for changes in the text content textView.addTextChangedListener(new TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { // Do something before the text changes } @Override public void onTextChanged(CharSequence s, int start, int before, int count) { // Do something when the text changes } @Override public void afterTextChanged(Editable s) { // Do something after the text changes } });In this example, we find a TextView with the ID "my_text_view" and add a TextWatcher instance to it using the addTextChangedListener method. The TextWatcher has three callback methods: beforeTextChanged, onTextChanged, and afterTextChanged. These methods allow us to perform actions before, during, and after the text changes. The addTextChangedListener method belongs to the android.widget.TextView class, which is part of the Android framework's standard widget package. The package library is therefore android.widget.