Text selection events and notifications

class MyActivity : PdfActivity(), TextSelectionManager.OnTextSelectionChangeListener, TextSelectionManager.OnTextSelectionModeChangeListener {

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    requirePdfFragment().addOnTextSelectionModeChangeListener(this)
    requirePdfFragment().addOnTextSelectionChangeListener(this)
  }

  override fun onDestroy() {
    pdfFragment?.removeOnTextSelectionModeChangeListener(this)
    pdfFragment?.removeOnTextSelectionChangeListener(this)
    super.onDestroy()
  }

  override fun onEnterTextSelectionMode(controller: TextSelectionController) {
    Log.i(TAG, "Text selection mode has started.")
  }

  override fun onExitTextSelectionMode(controller: TextSelectionController) {
    Log.i(TAG, "Text selection mode has ended.")
  }

  override fun onBeforeTextSelectionChange(newTextSelection: TextSelection?, currentTextSelection: TextSelection?): Boolean {
    // Return `false` to prevent changes to the current selection state, if needed.
    return true
  }

  override fun onAfterTextSelectionChange(newTextSelection: TextSelection?, oldTextSelection: TextSelection?) {
    if (newTextSelection != null) {
      Log.i(TAG, "Selected text was: ${newTextSelection.text}")
    } else {
      Log.i(TAG, "Text selection is cleared.")
    }
  }

  companion object {
    private const val TAG = "MyActivity.TextSelection"
  }
}

public class MyActivity extends PdfActivity implements TextSelectionManager.OnTextSelectionChangeListener,
    TextSelectionManager.OnTextSelectionModeChangeListener{

  private static final String TAG = "MyActivity.TextSelection";

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      requirePdfFragment().addOnTextSelectionModeChangeListener(this);
      requirePdfFragment().addOnTextSelectionChangeListener(this);
  }

  @Override
  protected void onDestroy() {
      getPdfFragment().removeOnTextSelectionModeChangeListener(this);
      getPdfFragment().removeOnTextSelectionChangeListener(this);
      super.onDestroy();
  }

  @Override
  public void onEnterTextSelectionMode(@NonNull TextSelectionController controller) {
      Log.i(TAG, "Text selection mode has started.");
  }

  @Override
  public void onExitTextSelectionMode(@NonNull TextSelectionController controller) {
      Log.i(TAG, "Text selection mode has ended.");
  }

  @Override
  public boolean onBeforeTextSelectionChange(@Nullable TextSelection newTextSelection, @Nullable TextSelection currentTextSelection) {
      // Return `false` to prevent changes to the current selection state, if needed.
      return true;
  }

  @Override
  public void onAfterTextSelectionChange(@Nullable TextSelection newTextSelection, @Nullable TextSelection oldTextSelection) {
      if (newTextSelection != null) {
          Log.i(TAG, String.format("Selected text was: %s", newTextSelection.text));
      } else {
          Log.i(TAG, "Text selection is cleared.");
      }
  }
}