android实现双日期选择控件（可隐藏日，只显示年月）

在安卓开发中，会碰到选开始日期和结束日期的问题。特别是在使用Pad时，如果弹出一个Dialog，能够同时选择开始日期和结束日期，那将是极好的。我在开发中在DatePickerDialog的基础上做了修改，实现了这种Dialog。效果如下：

具体实现方法为：

先新建一个安卓项目DoubleDatePicker，在res/layout文件夹下新建date_picker_dialog.xml，内容如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:gravity="center_horizontal"
 android:orientation="horizontal"
 android:paddingTop="10dp" >

<LinearLayout
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:gravity="center_horizontal"
   android:orientation="vertical"
   android:padding="5dip" >

<TextView
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:text="开始日期" />

<DatePicker
     android:id="@+id/datePickerStart"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:calendarViewShown="false" />
 </LinearLayout>

<ImageView
   android:layout_width="wrap_content"
   android:layout_height="fill_parent"
   android:src="@drawable/fenge" />

<LinearLayout
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:gravity="center_horizontal"
   android:orientation="vertical"
   android:padding="5dip" >

<TextView
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:text="结束日期" />

<DatePicker
     android:id="@+id/datePickerEnd"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:calendarViewShown="false" />
 </LinearLayout>

</LinearLayout>

然后，在src的 默认包下新建文件DoubleDatePickerDialog.java，内容如下：

/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

package com.example.doubledatepicker;

import java.lang.reflect.Field;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.DatePicker;
import android.widget.DatePicker.OnDateChangedListener;

/**
* A simple dialog containing an {@link android.widget.DatePicker}.
*
* <p>
* See the <a href="{@docRoot}guide/topics/ui/controls/pickers.html">Pickers</a>
* guide.
* </p>
*/
public class DoubleDatePickerDialog extends AlertDialog implements OnClickListener, OnDateChangedListener {

private static final String START_YEAR = "start_year";
 private static final String END_YEAR = "end_year";
 private static final String START_MONTH = "start_month";
 private static final String END_MONTH = "end_month";
 private static final String START_DAY = "start_day";
 private static final String END_DAY = "end_day";

private final DatePicker mDatePicker_start;
 private final DatePicker mDatePicker_end;
 private final OnDateSetListener mCallBack;

/**
  * The callback used to indicate the user is done filling in the date.
  */
 public interface OnDateSetListener {

/**
    * @param view
    *      The view associated with this listener.
    * @param year
    *      The year that was set.
    * @param monthOfYear
    *      The month that was set (0-11) for compatibility with
    *      {@link java.util.Calendar}.
    * @param dayOfMonth
    *      The day of the month that was set.
    */
   void onDateSet(DatePicker startDatePicker, int startYear, int startMonthOfYear, int startDayOfMonth,
       DatePicker endDatePicker, int endYear, int endMonthOfYear, int endDayOfMonth);
 }

/**
  * @param context
  *      The context the dialog is to run in.
  * @param callBack
  *      How the parent is notified that the date is set.
  * @param year
  *      The initial year of the dialog.
  * @param monthOfYear
  *      The initial month of the dialog.
  * @param dayOfMonth
  *      The initial day of the dialog.
  */
 public DoubleDatePickerDialog(Context context, OnDateSetListener callBack, int year, int monthOfYear, int dayOfMonth) {
   this(context, 0, callBack, year, monthOfYear, dayOfMonth);
 }

public DoubleDatePickerDialog(Context context, int theme, OnDateSetListener callBack, int year, int monthOfYear,
     int dayOfMonth) {
   this(context, 0, callBack, year, monthOfYear, dayOfMonth, true);
 }

/**
  * @param context
  *      The context the dialog is to run in.
  * @param theme
  *      the theme to apply to this dialog
  * @param callBack
  *      How the parent is notified that the date is set.
  * @param year
  *      The initial year of the dialog.
  * @param monthOfYear
  *      The initial month of the dialog.
  * @param dayOfMonth
  *      The initial day of the dialog.
  */
 public DoubleDatePickerDialog(Context context, int theme, OnDateSetListener callBack, int year, int monthOfYear,
     int dayOfMonth, boolean isDayVisible) {
   super(context, theme);

mCallBack = callBack;

Context themeContext = getContext();
   setButton(BUTTON_POSITIVE, "确 定", this);
   setButton(BUTTON_NEGATIVE, "取 消", this);
   // setButton(BUTTON_POSITIVE,
   // themeContext.getText(android.R.string.date_time_done), this);
   setIcon(0);

LayoutInflater inflater = (LayoutInflater) themeContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
   View view = inflater.inflate(R.layout.date_picker_dialog, null);
   setView(view);
   mDatePicker_start = (DatePicker) view.findViewById(R.id.datePickerStart);
   mDatePicker_end = (DatePicker) view.findViewById(R.id.datePickerEnd);
   mDatePicker_start.init(year, monthOfYear, dayOfMonth, this);
   mDatePicker_end.init(year, monthOfYear, dayOfMonth, this);
   // updateTitle(year, monthOfYear, dayOfMonth);

// 如果要隐藏当前日期，则使用下面方法。
   if (!isDayVisible) {
     hidDay(mDatePicker_start);
     hidDay(mDatePicker_end);
   }
 }

/**
  * 隐藏DatePicker中的日期显示
  *
  * @param mDatePicker
  */
 private void hidDay(DatePicker mDatePicker) {
   Field[] datePickerfFields = mDatePicker.getClass().getDeclaredFields();
   for (Field datePickerField : datePickerfFields) {
     if ("mDaySpinner".equals(datePickerField.getName())) {
       datePickerField.setAccessible(true);
       Object dayPicker = new Object();
       try {
         dayPicker = datePickerField.get(mDatePicker);
       } catch (IllegalAccessException e) {
         e.printStackTrace();
       } catch (IllegalArgumentException e) {
         e.printStackTrace();
       }
       // datePicker.getCalendarView().setVisibility(View.GONE);
       ((View) dayPicker).setVisibility(View.GONE);
     }
   }
 }

public void onClick(DialogInterface dialog, int which) {
   // Log.d(this.getClass().getSimpleName(), String.format("which:％d",
   // which));
   // 如果是“取 消”按钮，则返回，如果是“确 定”按钮，则往下执行
   if (which == BUTTON_POSITIVE)
     tryNotifyDateSet();
 }

@Override
 public void onDateChanged(DatePicker view, int year, int month, int day) {
   if (view.getId() == R.id.datePickerStart)
     mDatePicker_start.init(year, month, day, this);
   if (view.getId() == R.id.datePickerEnd)
     mDatePicker_end.init(year, month, day, this);
   // updateTitle(year, month, day);
 }

/**
  * 获得开始日期的DatePicker
  *
  * @return The calendar view.
  */
 public DatePicker getDatePickerStart() {
   return mDatePicker_start;
 }

/**
  * 获得结束日期的DatePicker
  *
  * @return The calendar view.
  */
 public DatePicker getDatePickerEnd() {
   return mDatePicker_end;
 }

/**
  * Sets the start date.
  *
  * @param year
  *      The date year.
  * @param monthOfYear
  *      The date month.
  * @param dayOfMonth
  *      The date day of month.
  */
 public void updateStartDate(int year, int monthOfYear, int dayOfMonth) {
   mDatePicker_start.updateDate(year, monthOfYear, dayOfMonth);
 }

/**
  * Sets the end date.
  *
  * @param year
  *      The date year.
  * @param monthOfYear
  *      The date month.
  * @param dayOfMonth
  *      The date day of month.
  */
 public void updateEndDate(int year, int monthOfYear, int dayOfMonth) {
   mDatePicker_end.updateDate(year, monthOfYear, dayOfMonth);
 }

private void tryNotifyDateSet() {
   if (mCallBack != null) {
     mDatePicker_start.clearFocus();
     mDatePicker_end.clearFocus();
     mCallBack.onDateSet(mDatePicker_start, mDatePicker_start.getYear(), mDatePicker_start.getMonth(),
         mDatePicker_start.getDayOfMonth(), mDatePicker_end, mDatePicker_end.getYear(),
         mDatePicker_end.getMonth(), mDatePicker_end.getDayOfMonth());
   }
 }

@Override
 protected void onStop() {
   // tryNotifyDateSet();
   super.onStop();
 }

@Override
 public Bundle onSaveInstanceState() {
   Bundle state = super.onSaveInstanceState();
   state.putInt(START_YEAR, mDatePicker_start.getYear());
   state.putInt(START_MONTH, mDatePicker_start.getMonth());
   state.putInt(START_DAY, mDatePicker_start.getDayOfMonth());
   state.putInt(END_YEAR, mDatePicker_end.getYear());
   state.putInt(END_MONTH, mDatePicker_end.getMonth());
   state.putInt(END_DAY, mDatePicker_end.getDayOfMonth());
   return state;
 }

@Override
 public void onRestoreInstanceState(Bundle savedInstanceState) {
   super.onRestoreInstanceState(savedInstanceState);
   int start_year = savedInstanceState.getInt(START_YEAR);
   int start_month = savedInstanceState.getInt(START_MONTH);
   int start_day = savedInstanceState.getInt(START_DAY);
   mDatePicker_start.init(start_year, start_month, start_day, this);

int end_year = savedInstanceState.getInt(END_YEAR);
   int end_month = savedInstanceState.getInt(END_MONTH);
   int end_day = savedInstanceState.getInt(END_DAY);
   mDatePicker_end.init(end_year, end_month, end_day, this);

}
}

这些代码是以DatePickerDialog.java为基础修改的。总的来说，阅读源码是一种好习惯。这里面最需要注意的是hidDay方法，该方法如果调用，则隐藏“日”的选择框，只能选择“年月”。这个方法的实现也比较有难度，需要通过反射，找出DatePicker中表示日的字段，并将其设置为隐藏。

还有一点需要注意的是，为了让控件显示更加好看，我用了一张名字为fenge.png的图片，图片在我提供的源码中可以找到。

下面就需要编辑activity_main.xml了，这个内容相当简单，只要一个显示的text和一个button即可，代码如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:id="@+id/LinearLayout01"
 android:layout_width="fill_parent"
 android:layout_height="fill_parent"
 android:orientation="vertical" >

<EditText
   android:id="@+id/et"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:cursorVisible="false"
   android:editable="false" />

<Button
   android:id="@+id/dateBtn"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:text="日期对话框" />

</LinearLayout>

最后，在MainActivity.java中，加入测试代码：

package com.example.doubledatepicker;

import java.util.Calendar;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.DatePicker;
import android.widget.TextView;

public class MainActivity extends Activity {

Button btn;
 TextView et;

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

btn = (Button) findViewById(R.id.dateBtn);
   et = (TextView) findViewById(R.id.et);

btn.setOnClickListener(new View.OnClickListener() {
     Calendar c = Calendar.getInstance();

@Override
     public void onClick(View v) {
       // 最后一个false表示不显示日期，如果要显示日期，最后参数可以是true或者不用输入
       new DoubleDatePickerDialog(MainActivity.this, 0, new DoubleDatePickerDialog.OnDateSetListener() {

@Override
         public void onDateSet(DatePicker startDatePicker, int startYear, int startMonthOfYear,
             int startDayOfMonth, DatePicker endDatePicker, int endYear, int endMonthOfYear,
             int endDayOfMonth) {
           String textString = String.format("开始时间：％d-％d-％d\n结束时间：％d-％d-％d\n", startYear,
               startMonthOfYear + 1, startDayOfMonth, endYear, endMonthOfYear + 1, endDayOfMonth);
           et.setText(textString);
         }
       }, c.get(Calendar.YEAR), c.get(Calendar.MONTH), c.get(Calendar.DATE), true).show();
     }
   });
 }
}

可以看到，在新建DoubleDatePickerDialog时， 我们实现了一个new DoubleDatePickerDialog.OnDateSetListener()的匿名类，这个类被DoubleDatePickerDialog引用，当DoubleDatePickerDialog中的“确 定”按钮被点击时，就会调用匿名类的onDateSet方法。（这也是事件绑定的基本原理）。

DoubleDatePickerDialog构造函数的最后一个参数，true为显示日期，false为不显示日期。

当最后一个参数为true时，显示效果如下：

当最后一个参数为false时，显示如下

源码下载地址：http://xiazai.jb51.net/201701/yuanma/DoubleDatePicker_jb51.rar

来源：http://www.cnblogs.com/jilianggqq/p/4139510.html