安卓开发中的双日期选择控件（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"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3     android:layout_width="wrap_content" 4     android:layout_height="wrap_content" 5     android:gravity="center_horizontal" 6     android:orientation="horizontal" 7     android:paddingTop="10dp" > 8  9     <LinearLayout10         android:layout_width="wrap_content"11         android:layout_height="wrap_content"12         android:gravity="center_horizontal"13         android:orientation="vertical"14         android:padding="5dip" >15 16         <TextView17             android:layout_width="wrap_content"18             android:layout_height="wrap_content"19             android:text="开始日期" />20 21         <DatePicker22             android:id="@+id/datePickerStart"23             android:layout_width="wrap_content"24             android:layout_height="wrap_content"25             android:calendarViewShown="false" />26     </LinearLayout>27 28     <ImageView29         android:layout_width="wrap_content"30         android:layout_height="fill_parent"31         android:src="@drawable/fenge" />32 33     <LinearLayout34         android:layout_width="wrap_content"35         android:layout_height="wrap_content"36         android:gravity="center_horizontal"37         android:orientation="vertical"38         android:padding="5dip" >39 40         <TextView41             android:layout_width="wrap_content"42             android:layout_height="wrap_content"43             android:text="结束日期" />44 45         <DatePicker46             android:id="@+id/datePickerEnd"47             android:layout_width="wrap_content"48             android:layout_height="wrap_content"49             android:calendarViewShown="false" />50     </LinearLayout>51 52 </LinearLayout>

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

/*  2  * Copyright (C) 2007 The Android Open Source Project  3  *  4  * Licensed under the Apache License, Version 2.0 (the "License");  5  * you may not use this file except in compliance with the License.  6  * You may obtain a copy of the License at  7  *  8  *      http://www.apache.org/licenses/LICENSE-2.0  9  * 10  * Unless required by applicable law or agreed to in writing, software 11  * distributed under the License is distributed on an "AS IS" BASIS, 12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13  * See the License for the specific language governing permissions and 14  * limitations under the License. 15  */ 16  17 package com.example.doubledatepicker; 18  19 import java.lang.reflect.Field; 20  21 import android.app.AlertDialog; 22 import android.content.Context; 23 import android.content.DialogInterface; 24 import android.content.DialogInterface.OnClickListener; 25 import android.os.Bundle; 26 import android.view.LayoutInflater; 27 import android.view.View; 28 import android.widget.DatePicker; 29 import android.widget.DatePicker.OnDateChangedListener; 30  31 /** 32  * A simple dialog containing an {@link android.widget.DatePicker}. 33  * 34  * <p> 35  * See the <a href="{@docRoot}guide/topics/ui/controls/pickers.html">Pickers</a> 36  * guide. 37  * </p> 38  */ 39 public class DoubleDatePickerDialog extends AlertDialog implements OnClickListener, OnDateChangedListener { 40  41     private static final String START_YEAR = "start_year"; 42     private static final String END_YEAR = "end_year"; 43     private static final String START_MONTH = "start_month"; 44     private static final String END_MONTH = "end_month"; 45     private static final String START_DAY = "start_day"; 46     private static final String END_DAY = "end_day"; 47  48     private final DatePicker mDatePicker_start; 49     private final DatePicker mDatePicker_end; 50     private final OnDateSetListener mCallBack; 51  52     /** 53      * The callback used to indicate the user is done filling in the date. 54      */ 55     public interface OnDateSetListener { 56  57         /** 58          * @param view 59          *            The view associated with this listener. 60          * @param year 61          *            The year that was set. 62          * @param monthOfYear 63          *            The month that was set (0-11) for compatibility with 64          *            {@link java.util.Calendar}. 65          * @param dayOfMonth 66          *            The day of the month that was set. 67          */ 68         void onDateSet(DatePicker startDatePicker, int startYear, int startMonthOfYear, int startDayOfMonth, 69                 DatePicker endDatePicker, int endYear, int endMonthOfYear, int endDayOfMonth); 70     } 71  72     /** 73      * @param context 74      *            The context the dialog is to run in. 75      * @param callBack 76      *            How the parent is notified that the date is set. 77      * @param year 78      *            The initial year of the dialog. 79      * @param monthOfYear 80      *            The initial month of the dialog. 81      * @param dayOfMonth 82      *            The initial day of the dialog. 83      */ 84     public DoubleDatePickerDialog(Context context, OnDateSetListener callBack, int year, int monthOfYear, int dayOfMonth) { 85         this(context, 0, callBack, year, monthOfYear, dayOfMonth); 86     } 87  88     public DoubleDatePickerDialog(Context context, int theme, OnDateSetListener callBack, int year, int monthOfYear, 89             int dayOfMonth) { 90         this(context, 0, callBack, year, monthOfYear, dayOfMonth, true); 91     } 92  93     /** 94      * @param context 95      *            The context the dialog is to run in. 96      * @param theme 97      *            the theme to apply to this dialog 98      * @param callBack 99      *            How the parent is notified that the date is set.100      * @param year101      *            The initial year of the dialog.102      * @param monthOfYear103      *            The initial month of the dialog.104      * @param dayOfMonth105      *            The initial day of the dialog.106      */107     public DoubleDatePickerDialog(Context context, int theme, OnDateSetListener callBack, int year, int monthOfYear,108             int dayOfMonth, boolean isDayVisible) {109         super(context, theme);110 111         mCallBack = callBack;112 113         Context themeContext = getContext();114         setButton(BUTTON_POSITIVE, "确 定", this);115         setButton(BUTTON_NEGATIVE, "取 消", this);116         // setButton(BUTTON_POSITIVE,117         // themeContext.getText(android.R.string.date_time_done), this);118         setIcon(0);119 120         LayoutInflater inflater = (LayoutInflater) themeContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);121         View view = inflater.inflate(R.layout.date_picker_dialog, null);122         setView(view);123         mDatePicker_start = (DatePicker) view.findViewById(R.id.datePickerStart);124         mDatePicker_end = (DatePicker) view.findViewById(R.id.datePickerEnd);125         mDatePicker_start.init(year, monthOfYear, dayOfMonth, this);126         mDatePicker_end.init(year, monthOfYear, dayOfMonth, this);127         // updateTitle(year, monthOfYear, dayOfMonth);128 129         // 如果要隐藏当前日期，则使用下面方法。130         if (!isDayVisible) {131             hidDay(mDatePicker_start);132             hidDay(mDatePicker_end);133         }134     }135 136     /**137      * 隐藏DatePicker中的日期显示138      * 139      * @param mDatePicker140      */141     private void hidDay(DatePicker mDatePicker) {142         Field[] datePickerfFields = mDatePicker.getClass().getDeclaredFields();143         for (Field datePickerField : datePickerfFields) {144             if ("mDaySpinner".equals(datePickerField.getName())) {145                 datePickerField.setAccessible(true);146                 Object dayPicker = new Object();147                 try {148                     dayPicker = datePickerField.get(mDatePicker);149                 } catch (IllegalAccessException e) {150                     e.printStackTrace();151                 } catch (IllegalArgumentException e) {152                     e.printStackTrace();153                 }154                 // datePicker.getCalendarView().setVisibility(View.GONE);155                 ((View) dayPicker).setVisibility(View.GONE);156             }157         }158     }159 160     public void onClick(DialogInterface dialog, int which) {161         // Log.d(this.getClass().getSimpleName(), String.format("which:%d",162         // which));163         // 如果是“取 消”按钮，则返回，如果是“确 定”按钮，则往下执行164         if (which == BUTTON_POSITIVE)165             tryNotifyDateSet();166     }167 168     @Override169     public void onDateChanged(DatePicker view, int year, int month, int day) {170         if (view.getId() == R.id.datePickerStart)171             mDatePicker_start.init(year, month, day, this);172         if (view.getId() == R.id.datePickerEnd)173             mDatePicker_end.init(year, month, day, this);174         // updateTitle(year, month, day);175     }176 177     /**178      * 获得开始日期的DatePicker179      *180      * @return The calendar view.181      */182     public DatePicker getDatePickerStart() {183         return mDatePicker_start;184     }185 186     /**187      * 获得结束日期的DatePicker188      *189      * @return The calendar view.190      */191     public DatePicker getDatePickerEnd() {192         return mDatePicker_end;193     }194 195     /**196      * Sets the start date.197      *198      * @param year199      *            The date year.200      * @param monthOfYear201      *            The date month.202      * @param dayOfMonth203      *            The date day of month.204      */205     public void updateStartDate(int year, int monthOfYear, int dayOfMonth) {206         mDatePicker_start.updateDate(year, monthOfYear, dayOfMonth);207     }208 209     /**210      * Sets the end date.211      *212      * @param year213      *            The date year.214      * @param monthOfYear215      *            The date month.216      * @param dayOfMonth217      *            The date day of month.218      */219     public void updateEndDate(int year, int monthOfYear, int dayOfMonth) {220         mDatePicker_end.updateDate(year, monthOfYear, dayOfMonth);221     }222 223     private void tryNotifyDateSet() {224         if (mCallBack != null) {225             mDatePicker_start.clearFocus();226             mDatePicker_end.clearFocus();227             mCallBack.onDateSet(mDatePicker_start, mDatePicker_start.getYear(), mDatePicker_start.getMonth(),228                     mDatePicker_start.getDayOfMonth(), mDatePicker_end, mDatePicker_end.getYear(),229                     mDatePicker_end.getMonth(), mDatePicker_end.getDayOfMonth());230         }231     }232 233     @Override234     protected void onStop() {235         // tryNotifyDateSet();236         super.onStop();237     }238 239     @Override240     public Bundle onSaveInstanceState() {241         Bundle state = super.onSaveInstanceState();242         state.putInt(START_YEAR, mDatePicker_start.getYear());243         state.putInt(START_MONTH, mDatePicker_start.getMonth());244         state.putInt(START_DAY, mDatePicker_start.getDayOfMonth());245         state.putInt(END_YEAR, mDatePicker_end.getYear());246         state.putInt(END_MONTH, mDatePicker_end.getMonth());247         state.putInt(END_DAY, mDatePicker_end.getDayOfMonth());248         return state;249     }250 251     @Override252     public void onRestoreInstanceState(Bundle savedInstanceState) {253         super.onRestoreInstanceState(savedInstanceState);254         int start_year = savedInstanceState.getInt(START_YEAR);255         int start_month = savedInstanceState.getInt(START_MONTH);256         int start_day = savedInstanceState.getInt(START_DAY);257         mDatePicker_start.init(start_year, start_month, start_day, this);258 259         int end_year = savedInstanceState.getInt(END_YEAR);260         int end_month = savedInstanceState.getInt(END_MONTH);261         int end_day = savedInstanceState.getInt(END_DAY);262         mDatePicker_end.init(end_year, end_month, end_day, this);263 264     }265 }

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"?> 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 3     android:id="@+id/LinearLayout01" 4     android:layout_width="fill_parent" 5     android:layout_height="fill_parent" 6     android:orientation="vertical" > 7  8     <EditText 9         android:id="@+id/et"10         android:layout_width="fill_parent"11         android:layout_height="wrap_content"12         android:cursorVisible="false"13         android:editable="false" />14 15     <Button16         android:id="@+id/dateBtn"17         android:layout_width="fill_parent"18         android:layout_height="wrap_content"19         android:text="日期对话框" />20 21 </LinearLayout>

最后，在MainActivity.java中，加入测试代码：

package com.example.doubledatepicker; 2  3 import java.util.Calendar; 4  5 import android.app.Activity; 6 import android.os.Bundle; 7 import android.view.View; 8 import android.widget.Button; 9 import android.widget.DatePicker;10 import android.widget.TextView;11 12 public class MainActivity extends Activity {13 14     Button btn;15     TextView et;16 17     @Override18     protected void onCreate(Bundle savedInstanceState) {19         super.onCreate(savedInstanceState);20         setContentView(R.layout.activity_main);21 22         btn = (Button) findViewById(R.id.dateBtn);23         et = (TextView) findViewById(R.id.et);24 25         btn.setOnClickListener(new View.OnClickListener() {26             Calendar c = Calendar.getInstance();27 28             @Override29             public void onClick(View v) {30                 // 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31                 new DoubleDatePickerDialog(MainActivity.this, 0, new DoubleDatePickerDialog.OnDateSetListener() {32 33                     @Override34                     public void onDateSet(DatePicker startDatePicker, int startYear, int startMonthOfYear,35                             int startDayOfMonth, DatePicker endDatePicker, int endYear, int endMonthOfYear,36                             int endDayOfMonth) {37                         String textString = String.format("开始时间：%d-%d-%d\n结束时间：%d-%d-%d\n", startYear,38                                 startMonthOfYear + 1, startDayOfMonth, endYear, endMonthOfYear + 1, endDayOfMonth);39                         et.setText(textString);40                     }41                 }, c.get(Calendar.YEAR), c.get(Calendar.MONTH), c.get(Calendar.DATE), true).show();42             }43         });44     }45 }

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：https://github.com/jilianggqq/DoubleDatePicker