Timer

package sourceit.com.timer;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.Button;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;

public class MainActivity extends AppCompatActivity {
//
    @BindView(R.id.action_timer)
    Button actionTimer;
    @BindView(R.id.action_stopwatch)
    Button actionStopwatch;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);

        getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.container, TimerFragment.newInstance())
                .commit();
    }

    @OnClick(R.id.action_stopwatch)
    public void onClickStopwatch() {
        getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.container,
                        StopwatchFragment.newInstance())
                .addToBackStack(null)
                .commit();
    }

    @OnClick(R.id.action_timer)
    public void onClickTimer() {
        getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.container,
                        TimerFragment.newInstance())
                .addToBackStack(null)
                .commit();
    }

}
________________________________________________________________________________________________
package sourceit.com.timer;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import butterknife.OnLongClick;
import butterknife.Unbinder;

public class TimerFragment extends Fragment {

    private static final int START = 1;
    private static final int STOP = 2;
    int time = 30;
    int timeLongClick = 30;
    private boolean isStarted;
    @BindView(R.id.text_timer)
    TextView textTimer;
    Handler h = new Handler() {
        @Override
        public void dispatchMessage(Message msg) {
            if (msg.what == START) {
                textTimer.setText(String.valueOf(time));
                time--;
                if (time >= 0) {
                    h.sendEmptyMessageDelayed(START, 1_000);
                }
            } else if (msg.what == STOP) {
                stopTimer();
            }
        }
    };
    Unbinder unbinder;

    public static TimerFragment newInstance() {
        TimerFragment fragment = new TimerFragment();
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View root = inflater.inflate(R.layout.fragment_timer, container, false);
        unbinder = ButterKnife.bind(this, root);
        startTimer();
        return root;
    }

    public void startTimer() {
        isStarted = true;
        h.sendEmptyMessage(START);
    }

    public void stopTimer() {
        isStarted = false;
        h.removeMessages(START);
    }

    @OnClick(R.id.text_timer)
    public void onNumberClick() {
        if (isStarted) {
            stopTimer();
        } else {
            startTimer();
        }
    }

    @OnLongClick(R.id.text_timer)
    public boolean onNumberLongClick() {
        stopTimer();
        textTimer.setText(String.valueOf(timeLongClick));
        time = timeLongClick;
        return true;
    }

    @Override
    public void onDestroyView() {
        unbinder.unbind();
        h.removeMessages(START);
        h.removeMessages(STOP);
        super.onDestroyView();
    }
}
_____________________________________________________________________________________

package sourceit.com.timer;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;
import butterknife.OnLongClick;
import butterknife.Unbinder;

public class StopwatchFragment extends Fragment {

    private static final int START = 1;
    private static final int STOP = 2;
    private int seconds = 0;
    private boolean isStarted;
    @BindView(R.id.text_stopwatch)
    TextView textStopwatch;
    Handler h = new Handler() {
        @Override
        public void dispatchMessage(Message msg) {
            int hours = seconds / 3600;
            int minutes = (seconds % 3600) / 60;
            int sec = seconds % 60;
            String time = String.format("%d:%02d:%02d", hours, minutes, sec);
            textStopwatch.setText(time);
            if (msg.what == START) {
                seconds++;
                if (isStarted) {
                    h.sendEmptyMessageDelayed(START, 1000);
                }
            } else if (msg.what == STOP) {
                stopStopwatch();
            }
        }
    };
    Unbinder unbinder;

    public static StopwatchFragment newInstance() {
        StopwatchFragment fragment = new StopwatchFragment();
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View root = inflater.inflate(R.layout.fragment_stopwatch, container, false);
        unbinder = ButterKnife.bind(this, root);
        startStopwatch();
        return root;
    }

    public void startStopwatch() {
        isStarted = true;
        h.sendEmptyMessage(START);
    }

    public void stopStopwatch() {
        isStarted = false;
        h.removeMessages(START);
    }

    @OnClick(R.id.text_stopwatch)
    public void onStopwatchClick() {
        if (isStarted) {
            stopStopwatch();
        } else {
            startStopwatch();
        }
    }

    @OnLongClick(R.id.text_stopwatch)
    public boolean onStopWatchLongClick() {
        stopStopwatch();
        seconds = 0;
        return true;
    }

    @Override
    public void onDestroyView() {
        unbinder.unbind();
        h.removeMessages(START);
        h.removeMessages(STOP);
        super.onDestroyView();
    }

}

______________________________________________________________

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="sourceit.com.timer.MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">


        <Button
            android:id="@+id/action_timer"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="@string/action_timer" />

        <Button
            android:id="@+id/action_stopwatch"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="@string/action_stopwatch" />

    </LinearLayout>

    <FrameLayout
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    </FrameLayout>


</LinearLayout>

______________________________________________________________________

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/activity_second"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin">

    <TextView
        android:id="@+id/text_timer"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:textSize="80sp" />
</RelativeLayout>

_________________________________________________________________

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/activity_second"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin">

    <TextView
        android:id="@+id/text_stopwatch"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:textSize="50sp" />
</RelativeLayout>