public
class
DateUtil {
public
static
String formattedTime(Date date): String {
SimpleDateFormat sdf =
new
SimpleDateFormat(
"...."
);
return
sdf.format(date);
}
}
public
class
ClockRepository {
private
static
final
TIME_KEY =
"mTime"
;
private
final
SharedPreferences prefs = ,,,
private
void
saveTime(
long
time) {
prefs.editor()
.putLong(TIME_KEY, time);
.apply();
}
public
String readTime() {
long
time = pref.getLong(TIME_KEY, 0L);
return
DateUtil.formattedTime(time);
}
}
public
class
ClockActivity
extends
AppCompatActivity() {
private
ClockRepository clockRepository;
@Override
public
void
onCreate(...) {
super
.onCreate(...);
setContentView(...);
clockRepository =
new
ClockRepository();
setupViews();
}
private
void
setupViews() {
btnStart.setOnClickListener(
new
View.OnClickListener() {
@Override
public
void
onClick(View view) {
saveCurrentTime();
}
});
}
private
void
saveCurrentTime() {
clockRepository.saveTime(System.currentTimeMills(););
tVSecond.setText(clockRepository.readTime());
}
}