直接上程式碼：
MainActivity：

package wkk.demo6;

import android.app.AlertDialog;
import android.app.DatePickerDialog;
import android.app.TimePickerDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.LayoutInflater;
import
 
 android.view.View;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.TimePicker;

import java.util.Calendar;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Button showdailogTwo;
    private
 
 Button showdailog;
    private Button time;
    //選擇日期Dialog
    private DatePickerDialog datePickerDialog;
    //選擇時間Dialog
    private TimePickerDialog timePickerDialog;

    private Calendar calendar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        showdailogTwo = (Button) findViewById(R.id.showdailogTwo);
        showdailog = (Button) findViewById(R.id.showdailog);
        time = (Button) findViewById(R.id.time);

        time.setOnClickListener(this
 
);
        showdailogTwo.setOnClickListener(this);
        showdailog.setOnClickListener(this);
        calendar = Calendar.getInstance();
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.showdailog:
                showDailog();
                break;
            case R.id.showdailogTwo:
                showDialogTwo();
                break;
            case R.id.time:
                showTime();
                break;
        }
    }



    private void showDailog() {
        datePickerDialog = new DatePickerDialog(
                this, new DatePickerDialog.OnDateSetListener() {
            @Override
            public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
                //monthOfYear 得到的月份會減1所以我們要加1
                String time = String.valueOf(year) + "　" + String.valueOf(monthOfYear + 1) + "  " + Integer.toString(dayOfMonth);
                Log.d("測試", time);
            }
        },
                calendar.get(Calendar.YEAR),
                calendar.get(Calendar.MONTH),
                calendar.get(Calendar.DAY_OF_MONTH));
        datePickerDialog.show();
        //自動彈出鍵盤問題解決
        datePickerDialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN);
    }


    private void showDialogTwo() {
        View view = LayoutInflater.from(this).inflate(R.layout.dialog_date, null);
        final DatePicker startTime = (DatePicker) view.findViewById(R.id.st);
        final DatePicker endTime = (DatePicker) view.findViewById(R.id.et);
        startTime.updateDate(startTime.getYear(), startTime.getMonth(), 01);
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("選擇時間");
        builder.setView(view);
        builder.setPositiveButton("確定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                int month = startTime.getMonth() + 1;
                String st = "" + startTime.getYear() + month + startTime.getDayOfMonth();
                int month1 = endTime.getMonth() + 1;
                String et = "" + endTime.getYear() + month1 + endTime.getDayOfMonth();
            }
        });
        builder.setNegativeButton("取消", null);
        AlertDialog dialog = builder.create();
        dialog.show();
        //自動彈出鍵盤問題解決
        dialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN);
    }

    private void showTime() {
        timePickerDialog = new TimePickerDialog(this, new TimePickerDialog.OnTimeSetListener() {
            @Override
            public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
                Log.d("測試", Integer.toString(hourOfDay));
                Log.d("測試", Integer.toString(minute));
            }
        }, calendar.get(Calendar.HOUR_OF_DAY), calendar.get(Calendar.MINUTE), true);
        timePickerDialog.show();
        timePickerDialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN);
    }
}

activity_main.xml

<?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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="wkk.demo6.MainActivity">

    <Button
        android:text="日期選擇"
        android:id="@+id/showdailog"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/showdailogTwo"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="日期選擇-雙" />
    <Button
        android:id="@+id/time"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="時間選擇" />

</LinearLayout>

dialog_date.xml

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


    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:layout_marginTop="15dp"
        android:text="開始時間" />

    <DatePicker
        android:id="@+id/st"
        android:layout_width="wrap_content"
        android:layout_height="190dp"
        android:calendarViewShown="false"></DatePicker>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:text="結束時間" />

    <DatePicker
        android:id="@+id/et"
        android:layout_width="wrap_content"
        android:layout_height="190dp"
        android:calendarViewShown="false"></DatePicker>


</LinearLayout>

效果如下：