$Android中日期和时间选择器的实现

　　创建日期或时间选择窗口需要弹出Dialog的时候，Activity类的showDialog方法已经弃用了，而推荐使用的是DialogFragment，本文总结一下其具体用法.

　　（一）日期选择器

　　1、创建MyDatePickerDialog类，继承自DatePickerDialog类，实现构造方法，重写onDateChanged方法：

 import android.app.DatePickerDialog;
 import android.content.Context;
 import android.widget.DatePicker;

 public class MyDatePickerDialog extends DatePickerDialog {

     public MyDatePickerDialog (Context context, OnDateSetListener callBack,
             int year, int monthOfYear, int dayOfMonth) {
         super(context, callBack, year, monthOfYear, dayOfMonth);

         this.setTitle("选择任务的日期");
         this.setButton2("取消", (OnClickListener)null);
         this.setButton("确定", this);  //setButton和this参数组合表示这个按钮是确定按钮

     }

     @Override
     public void onDateChanged(DatePicker view, int year, int month, int day) {
         super.onDateChanged(view, year, month, day);
         this.setTitle("选择任务的日期");
     }

 }

　　注：隐藏日期选择器的“日”选择项的方法：在MyDatePickerDialog的构造方法中添加一个参数：代表日期选择器类型的整型参数，比如0代表年月日都显示，1表示只显示年和月等，然后用如下代码来隐藏“日”选择项（隐藏年月的方法同理，时间选择器也同理）：

 　　　　 // 获取当前系统的语言
         Locale locale = context.getResources().getConfiguration().locale;
         String language = locale.getLanguage();
 　　　　　　  // 隐藏日选择栏
             if (language.endsWith("zh")) {
                 ((ViewGroup) ((ViewGroup) this.getDatePicker().getChildAt(0))
                         .getChildAt(0)).getChildAt(2).setVisibility(View.GONE);
             } else {
                 ((ViewGroup) ((ViewGroup) this.getDatePicker().getChildAt(0))
                         .getChildAt(0)).getChildAt(1).setVisibility(View.GONE);
             }

　　2、创建DatePickerFragment类，继承自DialogFragment类并实现DatePickerDialog.OnDateSetListener接口，重写其onCreateDialog和onDateSet方法：

 import java.util.Calendar;

 import android.app.Dialog;
 import android.app.DialogFragment;
 import android.os.Bundle;
 import android.widget.DatePicker;
 import android.app.DatePickerDialog;

 public class DatePickerFragment extends DialogFragment implements
         DatePickerDialog.OnDateSetListener {
     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         final Calendar c = Calendar.getInstance();
         int year = c.get(Calendar.YEAR);
         int month = c.get(Calendar.MONTH);
         int day = c.get(Calendar.DAY_OF_MONTH);
         return new MyDatePickerDialog(getActivity(), this, year, month, day);
     }

     @Override
     public void onDateSet(DatePicker view, int year, int month, int day) {

     }

 }

　　3、在活动中显示日期选择器

 　　　　　　  DatePickerFragment datePickerFrg = new DatePickerFragment() {
                 @Override
                 public void onDateSet(DatePicker view, int year, int month,
                         int day) {
                     Log.d("DateSet","选择的日期是：" + year +"-" + (month + 1) + "-" + day);                }
             };
             datePickerFrg.show(getFragmentManager(), "datePickerFrg");

　　效果：

　　（二）时间选择器

　　时间选择器的使用其实和日期选择器差不多.

　　1、创建MyTimePickerDialog类，继承自TimePickerDialog，实现构造方法，重写onTimeChanged方法：

 import android.app.TimePickerDialog;
 import android.content.Context;
 import android.content.DialogInterface.OnClickListener;
 import android.widget.TimePicker;

 public class MyTimePickerDialog extends TimePickerDialog {

     public MyTimePickerDialog (Context context, OnTimeSetListener callBack,
             int hourOfDay, int minute, boolean is24HourView) {
         super(context, callBack, hourOfDay, minute, is24HourView);

         this.setTitle("选择任务的时间");
         this.setButton2("取消", (OnClickListener)null);
         this.setButton("确定", this);  //setButton和this参数组合表示这个按钮是确定按钮
     }

     @Override
     public void onTimeChanged(TimePicker view, int hourOfDay, int minute) {
         super.onTimeChanged(view, hourOfDay, minute);
         this.setTitle("选择任务的时间");
     }

 }

　　2、创建TimePickerFragment类，继承自DialogFragment类并实现TimePickerDialog.OnTimeSetListener接口，重写其onCreateDialog和onTimeSet方法：

 public class TimePickerFragment extends DialogFragment implements
         TimePickerDialog.OnTimeSetListener {

     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         final Calendar calendar = Calendar.getInstance();
         int hour = calendar.get(Calendar.HOUR_OF_DAY);
         int minute = calendar.get(Calendar.MINUTE);

         return new MyTimePickerDialog(getActivity(), this, hour, minute,
                 DateFormat.is24HourFormat(getActivity()));
     }

     @Override
     public void onTimeSet(TimePicker view, int hourOfDay, int minute) {

     }
 }

　　3、在活动中显示时间选择器：

 　　　　　　  TimePickerFragment timePickerFrg = new TimePickerFragment() {
                 @Override
                 public void onTimeSet(android.widget.TimePicker view,
                         int hourOfDay, int minute) {
                     Log.d("TimeSet", "选择的时间是：" + hourOfDay + ":" + minute);
                 };
             };
             timePickerFrg.show(getFragmentManager(), "timePickerFrg");

　　效果：