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:
1 <?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 <LinearLayout 10 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 <TextView 17 android:layout_width="wrap_content" 18 android:layout_height="wrap_content" 19 android:text="开始日期" /> 20 21 <DatePicker 22 android:id="@+id/datePickerStart" 23 android:layout_width="wrap_content" 24 android:layout_height="wrap_content" 25 android:calendarViewShown="false" /> 26 </LinearLayout> 27 28 <ImageView 29 android:layout_width="wrap_content" 30 android:layout_height="fill_parent" 31 android:src="@drawable/fenge" /> 32 33 <LinearLayout 34 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 <TextView 41 android:layout_width="wrap_content" 42 android:layout_height="wrap_content" 43 android:text="结束日期" /> 44 45 <DatePicker 46 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:
1 /* 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 year 101 * The initial year of the dialog. 102 * @param monthOfYear 103 * The initial month of the dialog. 104 * @param dayOfMonth 105 * 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 mDatePicker 140 */ 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 @Override 169 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DatePicker 179 * 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DatePicker 188 * 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 year 199 * The date year. 200 * @param monthOfYear 201 * The date month. 202 * @param dayOfMonth 203 * 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 year 213 * The date year. 214 * @param monthOfYear 215 * The date month. 216 * @param dayOfMonth 217 * 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 @Override 234 protected void onStop() { 235 // tryNotifyDateSet(); 236 super.onStop(); 237 } 238 239 @Override 240 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 @Override 252 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:
1 <?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 <Button 16 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:
1 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 @Override 18 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 @Override 29 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 @Override 34 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