How to make a sound when the stopwatch is finished in the ANDROID STUDIO?

Good evening!

I am developing a timer and I do not know how to enter a warning sound to notify that the timer has zeroed.

Could you help me?

Follow the code:

package coleti.a.homebrew;

import android.content.Context; import android.content.SharedPreferences; import android.os.CountDownTimer; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.view.inputmethod.InputMethodManager; import android.widget.Button; import android.widget.EditText; import android.widget.TextView; import android.widget.Toast;

import java.util.Locale;

public class testcronometro extends AppCompatActivity {

private EditText mEditTextInput;
private TextView mTextViewCountDown;
private Button mButtonSet;
private Button mButtonStartPause;
private Button mButtonReset;

private CountDownTimer mCountDownTimer;

private boolean mTimerRunning;

private long mStartTimeInMillis;
private long mTimeLeftInMillis;
private long mEndTime;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_testecronometro);

    mEditTextInput = findViewById(R.id.edit_text_input);
    mTextViewCountDown = findViewById(R.id.text_view_countdown);

    mButtonSet = findViewById(R.id.button_set);
    mButtonStartPause = findViewById(R.id.button_start_pause);
    mButtonReset = findViewById(R.id.button_reset);

    mButtonSet.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String input = mEditTextInput.getText().toString();
            if (input.length() == 0) {
                Toast.makeText(testecronometro.this, "Field can't be empty", Toast.LENGTH_SHORT).show();
                return;
            }

            long millisInput = Long.parseLong(input) * 60000;
            if (millisInput == 0) {
                Toast.makeText(testecronometro.this, "Please enter a positive number", Toast.LENGTH_SHORT).show();
                return;
            }

            setTime(millisInput);
            mEditTextInput.setText("");
        }
    });

    mButtonStartPause.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (mTimerRunning) {
                pauseTimer();
            } else {
                startTimer();
            }
        }
    });

    mButtonReset.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            resetTimer();
        }
    });
}

private void setTime(long milliseconds) {
    mStartTimeInMillis = milliseconds;
    resetTimer();
    closeKeyboard();
}

private void startTimer() {
    mEndTime = System.currentTimeMillis() + mTimeLeftInMillis;

    mCountDownTimer = new CountDownTimer(mTimeLeftInMillis, 1000) {
        @Override
        public void onTick(long millisUntilFinished) {
            mTimeLeftInMillis = millisUntilFinished;
            updateCountDownText();
        }

        @Override
        public void onFinish() {
            mTimerRunning = false;
            updateWatchInterface();
        }
    }.start();

    mTimerRunning = true;
    updateWatchInterface();
}

private void pauseTimer() {
    mCountDownTimer.cancel();
    mTimerRunning = false;
    updateWatchInterface();
}

private void resetTimer() {
    mTimeLeftInMillis = mStartTimeInMillis;
    updateCountDownText();
    updateWatchInterface();
}

private void updateCountDownText() {
    int hours = (int) (mTimeLeftInMillis / 1000) / 3600;
    int minutes = (int) ((mTimeLeftInMillis / 1000) % 3600) / 60;
    int seconds = (int) (mTimeLeftInMillis / 1000) % 60;

    String timeLeftFormatted;
    if (hours > 0) {
        timeLeftFormatted = String.format(Locale.getDefault(),
                "%d:%02d:%02d", hours, minutes, seconds);
    } else {
        timeLeftFormatted = String.format(Locale.getDefault(),
                "%02d:%02d", minutes, seconds);
    }

    mTextViewCountDown.setText(timeLeftFormatted);
}

private void updateWatchInterface() {
    if (mTimerRunning) {
        mEditTextInput.setVisibility(View.INVISIBLE);
        mButtonSet.setVisibility(View.INVISIBLE);
        mButtonReset.setVisibility(View.INVISIBLE);
        mButtonStartPause.setText("Pause");
    } else {
        mEditTextInput.setVisibility(View.VISIBLE);
        mButtonSet.setVisibility(View.VISIBLE);
        mButtonStartPause.setText("Start");

        if (mTimeLeftInMillis < 1000) {
            mButtonStartPause.setVisibility(View.INVISIBLE);
        } else {
            mButtonStartPause.setVisibility(View.VISIBLE);
        }

        if (mTimeLeftInMillis < mStartTimeInMillis) {
            mButtonReset.setVisibility(View.VISIBLE);
        } else {
            mButtonReset.setVisibility(View.INVISIBLE);
        }
    }
}

private void closeKeyboard() {
    View view = this.getCurrentFocus();
    if (view != null) {
        InputMethodManager imm = (InputMethodManager) getSystemService(INPUT_METHOD_SERVICE);
        imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
    }
}

@Override
protected void onStop() {
    super.onStop();

    SharedPreferences prefs = getSharedPreferences("prefs", MODE_PRIVATE);
    SharedPreferences.Editor editor = prefs.edit();

    editor.putLong("startTimeInMillis", mStartTimeInMillis);
    editor.putLong("millisLeft", mTimeLeftInMillis);
    editor.putBoolean("timerRunning", mTimerRunning);
    editor.putLong("endTime", mEndTime);

    editor.apply();

    if (mCountDownTimer != null) {
        mCountDownTimer.cancel();
    }
}

@Override
protected void onStart() {
    super.onStart();

    SharedPreferences prefs = getSharedPreferences("prefs", MODE_PRIVATE);

    mStartTimeInMillis = prefs.getLong("startTimeInMillis", 600000);
    mTimeLeftInMillis = prefs.getLong("millisLeft", mStartTimeInMillis);
    mTimerRunning = prefs.getBoolean("timerRunning", false);

    updateCountDownText();
    updateWatchInterface();

    if (mTimerRunning) {
        mEndTime = prefs.getLong("endTime", 0);
        mTimeLeftInMillis = mEndTime - System.currentTimeMillis();

        if (mTimeLeftInMillis < 0) {
            mTimeLeftInMillis = 0;
            mTimerRunning = false;
            updateCountDownText();
            updateWatchInterface();
        } else {
            startTimer();
        }
    }
}

}