我当前正在开发一个应用程序，在这个应用程序中，您需要能够选择日期。我通过显示DatePickerDialog并将值应用于EditText解决了此问题。我的同事告诉我，我不应该在函数中创建新对象，而应该将其声明为变量。
final Calendar c = Calendar.getInstance();
int mYear = c.get(Calendar.YEAR);
int mMonth = c.get(Calendar.MONTH);
int mDay = c.get(Calendar.DAY_OF_MONTH);
DatePickerDialog datePickerDialog = new DatePickerDialog(this,
new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet(DatePicker view, int year,
int monthOfYear, int dayOfMonth) {
startDate.setText(year + "-" +(monthOfYear + 1) + "-" + dayOfMonth);
}
}, mYear, mMonth, mDay);
//datePickerDialog.onDateChanged();
datePickerDialog.getDatePicker().setMinDate(System.currentTimeMillis());
datePickerDialog.show();
这是一种好习惯还是有更好的方法来解决这个问题？
答案 0 :(得分：0)
尝试此操作，我们可以为此方法创建自定义日期选择器：
public class TimePickerDialogCustom extends Dialog implements View.OnClickListener {
public Activity c;
public Dialog d;
public RelativeLayout close;
TextView time;
private Button ok;
private TimePicker timePicker;
int status;
AlexPoppinsLightTextView error_msg_txtView;
public TimePickerDialogCustom(FragmentActivity a, TextView time, int status) {
super(a);
this.c = a;
this.time = time;
this.status = status;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.pick_time_layout);
close = findViewById(R.id.closepopup);
ok = findViewById(R.id.btn_ok_time);
timePicker = findViewById(R.id.tp_for_activity);
AppGlobalValidation.hideKeyboard(getContext());
if (status == 1) {
SimpleDateFormat displayFormat = new SimpleDateFormat("HH:mm");
SimpleDateFormat parseFormat = new SimpleDateFormat("hh:mm a");
try {
Date date = parseFormat.parse(time.getText().toString());
String time = displayFormat.format(date); //which is from server;
String splitTime[] = time.split(":");
int hours = Integer.parseInt(splitTime[0]);
int minutes = Integer.parseInt(splitTime[1]);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
timePicker.setHour(hours);
timePicker.setMinute(minutes);
}
} catch (ParseException e) {
e.printStackTrace();
}
} else if (status == 2) {
SimpleDateFormat displayFormat = new SimpleDateFormat("HH:mm");
SimpleDateFormat parseFormat = new SimpleDateFormat("hh:mm a");
try {
Date date = parseFormat.parse(time.getText().toString());
String time = displayFormat.format(date); //which is from server;
String splitTime[] = time.split(":");
int hours = Integer.parseInt(splitTime[0]);
int minutes = Integer.parseInt(splitTime[1]);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
timePicker.setHour(hours);
timePicker.setMinute(minutes);
}
} catch (ParseException e) {
e.printStackTrace();
}
}
error_msg_txtView = findViewById(R.id.error_msg_txtView);
close.setOnClickListener(this);
ok.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (status == 1) {
int hour = timePicker.getCurrentHour();
int minute = timePicker.getCurrentMinute();
if (hour >= 0 && hour < 12) {
error_msg_txtView.setVisibility(View.GONE);
time.setText(AppGlobalValidation.convertTo12Hour("" + hour + ":" + "" + minute));
AppGlobalValidation.hideKeyboard(getContext());
dismiss();
} else {
error_msg_txtView.setVisibility(View.VISIBLE);
error_msg_txtView.setText("Please Select Morning");
}
} else if (status == 2) {
int hour = timePicker.getCurrentHour();
int minute = timePicker.getCurrentMinute();
if (hour >= 12 && hour < 18) {
error_msg_txtView.setVisibility(View.GONE);
time.setText(AppGlobalValidation.convertTo12Hour("" + hour + ":" + "" + minute));
dismiss();
AppGlobalValidation.hideKeyboard(getContext());
} else {
error_msg_txtView.setVisibility(View.VISIBLE);
error_msg_txtView.setText("Please Select Afternoon ");
}
}
}
@Override
public void onClick(View view) {
dismiss();
AppGlobalValidation.hideKeyboard(getContext());
}
}
创建此方法后，可在您的活动或片段中调用此方法：
在单击侦听器上调用此方法：
TimePickerDialogCustom timePickerDialogCustom = new
TimePickerDialogCustom(getActivity(), morning_time_txtView, 1);
timePickerDialogCustom.show();
timePickerDialogCustom.setCancelable(false);
timePickerDialogCustom.setCanceledOnTouchOutside(true);
答案 1 :(得分：0)
我建议
LocalDate代替Calendar。 Calendar设计欠佳，已经过时。所以您的代码片段变成了这样的东西：
LocalDate today = LocalDate.now(ZoneId.systemDefault());
int mYear = today.getYear();
Month mMonth = today.getMonth();
int mDay = today.getDayOfMonth();
DatePickerDialog datePickerDialog = new DatePickerDialog(this,
new DatePickerDialog.OnDateSetListener() {
@Override
public void onDateSet(DatePicker view, int year,
int monthOfYear, int dayOfMonth) {
DateTimeFormatter dateFormatter = DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM);
LocalDate date = LocalDate.of(mYear, monthOfYear + 1, dayOfMonth);
startDate.setText(date.format(dateFormatter));
}
}, mYear, mMonth.getValue() - 1, mDay);
是的，java.time中的类在旧的和更新的Android设备上都能很好地工作。他们只需要至少 Java 6 。
org.threeten.bp导入日期和时间类。java.time。java.time向Java 6和7（JSR-310的ThreeTen）的反向端口。