Activity EditTask

package corso.java.todotasks;

import androidx.appcompat.app.AppCompatActivity;

import android.content.ContentValues;
import android.net.Uri;
import android.os.Bundle;
import android.provider.CalendarContract;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

import corso.java.todotasks.datamodel.Task;
import corso.java.todotasks.localpersist.TasksDao;

public class EditTaskActivity extends AppCompatActivity {

    public static class TextChangeListener implements TextWatcher {
        private final EditText first;
        private final EditText second;
        private final Button buttonToHandle;

        public TextChangeListener(EditText first, EditText second, Button buttonToHandle) {
            this.first = first;
            this.second = second;
            this.buttonToHandle = buttonToHandle;
        }

        @Override
        public void beforeTextChanged(CharSequence charSequence, int start, int before, int count) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int start, int before, int count) {
            buttonToHandle.setEnabled(first.getText().length() > 0 && second.getText().length() > 0);
        }

        @Override
        public void afterTextChanged(Editable editable) {

        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_edit_task);
        final SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
        Date today = Calendar.getInstance().getTime();

        final EditText txtTitle = findViewById(R.id.txt_title);
        final EditText txtDescription = findViewById(R.id.txt_description);
        final EditText txtStartDate = findViewById(R.id.txt_start_date);
        txtStartDate.setText(sdf.format(today));
        final EditText txtEndDate = findViewById(R.id.txt_end_date);
        txtEndDate.setText(sdf.format(today));
        final Button btnAdd = findViewById(R.id.btn_add);

        txtTitle.addTextChangedListener(new TextChangeListener(txtTitle, txtDescription, btnAdd));
        txtDescription.addTextChangedListener(new TextChangeListener(txtTitle, txtDescription, btnAdd));
        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                try {
                    TasksDao dao = new TasksDao(EditTaskActivity.this);
                    Task task = new Task.Builder()
                            .withTitle(txtTitle.getText().toString())
                            .withDescription(txtDescription.getText().toString())
                            .withStartDate(sdf.parse(txtStartDate.getText().toString()))
                            .withEndDate(sdf.parse(txtEndDate.getText().toString()))
                            .build();
                    dao.create(task);

                    Uri eventsUri = CalendarContract.Events.CONTENT_URI;
                    // oggetto di mappatura delle proprietà di un evento
                    ContentValues cv = new ContentValues();
                    cv.put(CalendarContract.Events.TITLE, task.title);
                    cv.put(CalendarContract.Events.DTSTART, task.startDate.getTime());
                    cv.put(CalendarContract.Events.DTEND, task.endDate.getTime());
                    cv.put(CalendarContract.Events.CALENDAR_ID, 1);
                    cv.put(CalendarContract.Events.EVENT_TIMEZONE, "Europe/Rome");
                    Uri uri = getContentResolver().insert(eventsUri, cv);
                    onBackPressed();
                } catch (Exception ex) {
                    Log.e("EditTaskActivity", "onClick: " + ex.toString());
                }
            }
        });
    }
}