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Android UI-自定义日历控件
2014年博客之星，投票地址点击打开链接
本篇博客笔者给大家分享一个日历控件，这里有个需求：要求显示当前月的日期，左右可以切换月份来查看日期。
我们想一想会如何去实现这样的一个控件，有开源的，但可能不太满足我们的特定的需求，这里笔者自定义了一个，读者可以根据自己的需求来修改代码。下面来说一下实现的思路：
首先我们要显示当前月份，自然我们要计算出当前的日期，并且把每一天对应到具体的星期，我们会有以下效果：
我们先想一下这样的效果用什么控件可以实现？很自然可以想到用网格视图GridView，但这里笔者使用的不是GridView, 因为使用GridView可能无法实现那个红色的圈圈，所以笔者决定自定义View，通过绘制来达到这样的效果。
这里我们定于一个日历卡，每一个月代表一个日历卡，我们通过计算每个月的日期，然后根据计算出来的位置绘制我们的数字。
我们知道，一个星期有七天，分别为星期日、星期一、星期二、星期三、星期四、星期五、星期六，这里有7列，一个月至少有28天，最多31天，所以至少应该有6行。组成6*7的方格图。
直接上代码：
package com.xiaowu.calendar;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.util.AttributeSet;import android.view.MotionEvent;import android.view.View;import android.view.ViewConfiguration;/** * 自定义日历卡 * * @author wuwenjie * */public class CalendarCard extends View { private static final int TOTAL_COL = 7; // 7列 private static final int TOTAL_ROW = 6; // 6行 private Paint mCirclePaint; // 绘制圆形的画笔 private Paint mTextPaint; // 绘制文本的画笔 private int mViewWidth; // 视图的宽度 private int mViewHeight; // 视图的高度 private int mCellSpace; // 单元格间距 private Row rows[] = new Row[TOTAL_ROW]; // 行数组，每个元素代表一行 private static CustomDate mShowDate; // 自定义的日期，包括year,month,day private OnCellClickListener mCellClickListener; // 单元格点击回调事件 private int touchSlop; // private boolean callBackCellSpace; private Cell mClickCell; private float mDownX; private float mDownY; /** * 单元格点击的回调接口 * * @author wuwenjie * */ public interface OnCellClickListener { void clickDate(CustomDate date); // 回调点击的日期 void changeDate(CustomDate date); // 回调滑动ViewPager改变的日期 } public CalendarCard(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(context); } public CalendarCard(Context context, AttributeSet attrs) { super(context, attrs); init(context); } public CalendarCard(Context context) { super(context); init(context); } public CalendarCard(Context context, OnCellClickListener listener) { super(context); this.mCellClickListener = listener; init(context); } private void init(Context context) { mTextPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mCirclePaint = new Paint(Paint.ANTI_ALIAS_FLAG); mCirclePaint.setStyle(Paint.Style.FILL); mCirclePaint.setColor(Color.parseColor("#F24949")); // 红色圆形 touchSlop = ViewConfiguration.get(context).getScaledTouchSlop(); initDate(); } private void initDate() { mShowDate = new CustomDate(); fillDate();// } private void fillDate() { int monthDay = DateUtil.getCurrentMonthDay(); // 今天 int lastMonthDays = DateUtil.getMonthDays(mShowDate.year, mShowDate.month - 1); // 上个月的天数 int currentMonthDays = DateUtil.getMonthDays(mShowDate.year, mShowDate.month); // 当前月的天数 int firstDayWeek = DateUtil.getWeekDayFromDate(mShowDate.year, mShowDate.month); boolean isCurrentMonth = false; if (DateUtil.isCurrentMonth(mShowDate)) { isCurrentMonth = true; } int day = 0; for (int j = 0; j < TOTAL_ROW; j++) { rows[j] = new Row(j); for (int i = 0; i < TOTAL_COL; i++) { int position = i + j * TOTAL_COL; // 单元格位置 // 这个月的 if (position >= firstDayWeek && position < firstDayWeek + currentMonthDays) { day++; rows[j].cells[i] = new Cell(CustomDate.modifiDayForObject( mShowDate, day), State.CURRENT_MONTH_DAY, i, j); // 今天 if (isCurrentMonth && day == monthDay ) { CustomDate date = CustomDate.modifiDayForObject(mShowDate, day); rows[j].cells[i] = new Cell(date, State.TODAY, i, j); } if (isCurrentMonth && day > monthDay) { // 如果比这个月的今天要大，表示还没到 rows[j].cells[i] = new Cell( CustomDate.modifiDayForObject(mShowDate, day), State.UNREACH_DAY, i, j); } // 过去一个月 } else if (position < firstDayWeek) { rows[j].cells[i] = new Cell(new CustomDate(mShowDate.year, mShowDate.month - 1, lastMonthDays - (firstDayWeek - position - 1)), State.PAST_MONTH_DAY, i, j); // 下个月 } else if (position >= firstDayWeek + currentMonthDays) { rows[j].cells[i] = new Cell((new CustomDate(mShowDate.year, mShowDate.month + 1, position - firstDayWeek - currentMonthDays + 1)), State.NEXT_MONTH_DAY, i, j); } } } mCellClickListener.changeDate(mShowDate); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); for (int i = 0; i < TOTAL_ROW; i++) { if (rows[i] != null) { rows[i].drawCells(canvas); } } } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); mViewWidth = w; mViewHeight = h; mCellSpace = Math.min(mViewHeight / TOTAL_ROW, mViewWidth / TOTAL_COL); if (!callBackCellSpace) { callBackCellSpace = true; } mTextPaint.setTextSize(mCellSpace / 3); } @Override public boolean onTouchEvent(MotionEvent event) { switch (event.getAction()) { case MotionEvent.ACTION_DOWN: mDownX = event.getX(); mDownY = event.getY(); break; case MotionEvent.ACTION_UP: float disX = event.getX() - mDownX; float disY = event.getY() - mDownY; if (Math.abs(disX) < touchSlop && Math.abs(disY) < touchSlop) { int col = (int) (mDownX / mCellSpace); int row = (int) (mDownY / mCellSpace); measureClickCell(col, row); } break; default: break; } return true; } /** * 计算点击的单元格 * @param col * @param row */ private void measureClickCell(int col, int row) { if (col >= TOTAL_COL || row >= TOTAL_ROW) return; if (mClickCell != null) { rows[mClickCell.j].cells[mClickCell.i] = mClickCell; } if (rows[row] != null) { mClickCell = new Cell(rows[row].cells[col].date, rows[row].cells[col].state, rows[row].cells[col].i, rows[row].cells[col].j); CustomDate date = rows[row].cells[col].date; date.week = col; mCellClickListener.clickDate(date); // 刷新界面 update(); } } /** * 组元素 * * @author wuwenjie * */ class Row { public int j; Row(int j) { this.j = j; } public Cell[] cells = new Cell[TOTAL_COL]; // 绘制单元格 public void drawCells(Canvas canvas) { for (int i = 0; i < cells.length; i++) { if (cells[i] != null) { cells[i].drawSelf(canvas); } } } } /** * 单元格元素 * * @author wuwenjie * */ class Cell { public CustomDate date; public State state; public int i; public int j; public Cell(CustomDate date, State state, int i, int j) { super(); this.date = date; this.state = state; this.i = i; this.j = j; } public void drawSelf(Canvas canvas) { switch (state) { case TODAY: // 今天 mTextPaint.setColor(Color.parseColor("#fffffe")); canvas.drawCircle((float) (mCellSpace * (i + 0.5)), (float) ((j + 0.5) * mCellSpace), mCellSpace / 3, mCirclePaint); break; case CURRENT_MONTH_DAY: // 当前月日期 mTextPaint.setColor(Color.BLACK); break; case PAST_MONTH_DAY: // 过去一个月 case NEXT_MONTH_DAY: // 下一个月 mTextPaint.setColor(Color.parseColor("#fffffe")); break; case UNREACH_DAY: // 还未到的天 mTextPaint.setColor(Color.GRAY); break; default: break; } // 绘制文字 String content = date.day + ""; canvas.drawText(content, (float) ((i + 0.5) * mCellSpace - mTextPaint .measureText(content) / 2), (float) ((j + 0.7) * mCellSpace - mTextPaint .measureText(content, 0, 1) / 2), mTextPaint); } } /** * * @author wuwenjie 单元格的状态 当前月日期，过去的月的日期，下个月的日期 */ enum State { TODAY,CURRENT_MONTH_DAY, PAST_MONTH_DAY, NEXT_MONTH_DAY, UNREACH_DAY; } // 从左往右划，上一个月 public void leftSlide() { if (mShowDate.month == 1) { mShowDate.month = 12; mShowDate.year -= 1; } else { mShowDate.month -= 1; } update(); } // 从右往左划，下一个月 public void rightSlide() { if (mShowDate.month == 12) { mShowDate.month = 1; mShowDate.year += 1; } else { mShowDate.month += 1; } update(); } public void update() { fillDate(); invalidate(); }}
/CustomCalendarView/src/com/xiaowu/calendar/DateUtil.java
package com.xiaowu.calendar;import android.annotation.SuppressLint;import android.util.Log;import java.text.ParseException;import java.text.SimpleDateFormat;import java.util.Calendar;import java.util.Date;import java.util.GregorianCalendar;public class DateUtil { public static String[] weekName = { "周日", "周一", "周二", "周三", "周四", "周五","周六" }; public static int getMonthDays(int year, int month) { if (month > 12) { month = 1; year += 1; } else if (month < 1) { month = 12; year -= 1; } int[] arr = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; int days = 0; if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) { arr[1] = 29; // 闰年2月29天 } try { days = arr[month - 1]; } catch (Exception e) { e.getStackTrace(); } return days; } public static int getYear() { return Calendar.getInstance().get(Calendar.YEAR); } public static int getMonth() { return Calendar.getInstance().get(Calendar.MONTH) + 1; } public static int getCurrentMonthDay() { return Calendar.getInstance().get(Calendar.DAY_OF_MONTH); } public static int getWeekDay() { return Calendar.getInstance().get(Calendar.DAY_OF_WEEK); } public static int getHour() { return Calendar.getInstance().get(Calendar.HOUR_OF_DAY); } public static int getMinute() { return Calendar.getInstance().get(Calendar.MINUTE); } public static CustomDate getNextSunday() { Calendar c = Calendar.getInstance(); c.add(Calendar.DATE, 7 - getWeekDay()+1); CustomDate date = new CustomDate(c.get(Calendar.YEAR), c.get(Calendar.MONTH)+1, c.get(Calendar.DAY_OF_MONTH)); return date; } public static int[] getWeekSunday(int year, int month, int day, int pervious) { int[] time = new int[3]; Calendar c = Calendar.getInstance(); c.set(Calendar.YEAR, year); c.set(Calendar.MONTH, month); c.set(Calendar.DAY_OF_MONTH, day); c.add(Calendar.DAY_OF_MONTH, pervious); time[0] = c.get(Calendar.YEAR); time[1] = c.get(Calendar.MONTH )+1; time[2] = c.get(Calendar.DAY_OF_MONTH); return time; } public static int getWeekDayFromDate(int year, int month) { Calendar cal = Calendar.getInstance(); cal.setTime(getDateFromString(year, month)); int week_index = cal.get(Calendar.DAY_OF_WEEK) - 1; if (week_index < 0) { week_index = 0; } return week_index; } @SuppressLint("SimpleDateFormat") public static Date getDateFromString(int year, int month) { String dateString = year + "-" + (month > 9 ? month : ("0" + month)) + "-01"; Date date = null; try { SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); date = sdf.parse(dateString); } catch (ParseException e) { System.out.println(e.getMessage()); } return date; } public static boolean isToday(CustomDate date){ return(date.year == DateUtil.getYear() && date.month == DateUtil.getMonth() && date.day == DateUtil.getCurrentMonthDay()); } public static boolean isCurrentMonth(CustomDate date){ return(date.year == DateUtil.getYear() && date.month == DateUtil.getMonth()); }}/CustomCalendarView/src/com/xiaowu/calendar/CustomDate.java、
package com.xiaowu.calendar;import java.io.Serializable;public class CustomDate implements Serializable{ private static final long serialVersionUID = 1L; public int year; public int month; public int day; public int week; public CustomDate(int year,int month,int day){ if(month > 12){ month = 1; year++; }else if(month <1){ month = 12; year--; } this.year = year; this.month = month; this.day = day; } public CustomDate(){ this.year = DateUtil.getYear(); this.month = DateUtil.getMonth(); this.day = DateUtil.getCurrentMonthDay(); } public static CustomDate modifiDayForObject(CustomDate date,int day){ CustomDate modifiDate = new CustomDate(date.year,date.month,day); return modifiDate; } @Override public String toString() { return year+"-"+month+"-"+day; } public int getYear() { return year; } public void setYear(int year) { this.year = year; } public int getMonth() { return month; } public void setMonth(int month) { this.month = month; } public int getDay() { return day; } public void setDay(int day) { this.day = day; } public int getWeek() { return week; } public void setWeek(int week) { this.week = week; }}所有绘制的操作在onDraw方面里实现，我这里定于了一个组对象Row、单元格元素Cell，通过Row[row].cell[col]来确定一个单元格，每次调用invalidate重绘视图。
接着，我们有一个需求需要左右切换，我们选用最熟悉的ViewPager，但这里有个问题，怎么实现无限循环呢，
这里我们传入一个日历卡数组，让ViewPager循环复用这几个日历卡，避免消耗内存。
/CustomCalendarView/src/com/xiaowu/calendar/CalendarViewAdapter.java
package com.xiaowu.calendar;import android.support.v4.view.PagerAdapter;import android.support.v4.view.ViewPager;import android.view.View;import android.view.ViewGroup;public class CalendarViewAdapter<V extends View> extends PagerAdapter { public static final String TAG = "CalendarViewAdapter"; private V[] views; public CalendarViewAdapter(V[] views) { super(); this.views = views; } @Override public Object instantiateItem(ViewGroup container, int position) { if (((ViewPager) container).getChildCount() == views.length) { ((ViewPager) container).removeView(views[position % views.length]); } ((ViewPager) container).addView(views[position % views.length], 0); return views[position % views.length]; } @Override public int getCount() { return Integer.MAX_VALUE; } @Override public boolean isViewFromObject(View view, Object object) { return view == ((View) object); } @Override public void destroyItem(ViewGroup container, int position, Object object) { ((ViewPager) container).removeView((View) container); } public V[] getAllItems() { return views; }}布局文件：
<?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:background="@color/white" android:orientation="vertical" > <RelativeLayout android:layout_width="match_parent" android:layout_height="50dp" android:background="#f6f1ea" > <ImageButton android:id="@+id/btnPreMonth" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerVertical="true" android:layout_marginRight="33dip" android:layout_toLeftOf="@+id/tvCurrentMonth" android:background="@drawable/ic_before" /> <ImageButton android:id="@+id/btnNextMonth" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerVertical="true" android:layout_marginLeft="33dip" android:layout_toRightOf="@+id/tvCurrentMonth" android:background="@drawable/ic_next" /> <TextView android:id="@+id/tvCurrentMonth" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_centerInParent="true" android:layout_centerVertical="true" android:text="11月" android:textColor="#323232" android:textSize="22sp" /> <ImageButton android:id="@+id/btnClose" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:layout_centerVertical="true" android:layout_marginRight="15dp" android:background="@drawable/ic_close" /> </RelativeLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginTop="15dp" android:orientation="vertical" > <TableLayout android:layout_width="match_parent" android:layout_height="20dip" android:layout_marginBottom="2dip" android:layout_marginTop="2dip" > <TableRow> <TextView style="@style/dateStyle" android:text="@string/sunday" android:textColor="@color/canlendar_text_color" /> <TextView style="@style/dateStyle" android:text="@string/monday" android:textColor="@color/canlendar_text_color" /> <TextView style="@style/dateStyle" android:text="@string/thesday" android:textColor="@color/canlendar_text_color" /> <TextView style="@style/dateStyle" android:text="@string/wednesday" android:textColor="@color/canlendar_text_color" /> <TextView style="@style/dateStyle" android:text="@string/thursday" android:textColor="@color/canlendar_text_color" /> <TextView style="@style/dateStyle" android:text="@string/friday" android:textColor="@color/canlendar_text_color" /> <TextView style="@style/dateStyle" android:text="@string/saturday" android:textColor="@color/canlendar_text_color" /> </TableRow> </TableLayout> </LinearLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="0dp" android:orientation="vertical" android:layout_weight="1" android:layout_marginTop="15dp"> <android.support.v4.view.ViewPager android:id="@+id/vp_calendar" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_gravity="center" android:background="@color/white" > </android.support.v4.view.ViewPager> </LinearLayout></LinearLayout>/CustomCalendarView/src/com/xiaowu/calendar/MainActivity.java
package com.xiaowu.calendar;import android.app.Activity;import android.os.Bundle;import android.support.v4.view.ViewPager;import android.support.v4.view.ViewPager.OnPageChangeListener;import android.view.View;import android.view.View.OnClickListener;import android.view.Window;import android.widget.ImageButton;import android.widget.TextView;import com.xiaowu.calendar.CalendarCard.OnCellClickListener;public class MainActivity extends Activity implements OnClickListener, OnCellClickListener{ private ViewPager mViewPager; private int mCurrentIndex = 498; private CalendarCard[] mShowViews; private CalendarViewAdapter<CalendarCard> adapter; private SildeDirection mDirection = SildeDirection.NO_SILDE; enum SildeDirection { RIGHT, LEFT, NO_SILDE; } private ImageButton preImgBtn, nextImgBtn; private TextView monthText; private ImageButton closeImgBtn; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.activity_main); mViewPager = (ViewPager) this.findViewById(R.id.vp_calendar); preImgBtn = (ImageButton) this.findViewById(R.id.btnPreMonth); nextImgBtn = (ImageButton) this.findViewById(R.id.btnNextMonth); monthText = (TextView) this.findViewById(R.id.tvCurrentMonth); closeImgBtn = (ImageButton) this.findViewById(R.id.btnClose); preImgBtn.setOnClickListener(this); nextImgBtn.setOnClickListener(this); closeImgBtn.setOnClickListener(this); CalendarCard[] views = new CalendarCard[3]; for (int i = 0; i < 3; i++) { views[i] = new CalendarCard(this, this); } adapter = new CalendarViewAdapter<>(views); setViewPager(); } private void setViewPager() { mViewPager.setAdapter(adapter); mViewPager.setCurrentItem(498); mViewPager.setOnPageChangeListener(new OnPageChangeListener() { @Override public void onPageSelected(int position) { measureDirection(position); updateCalendarView(position); } @Override public void onPageScrolled(int arg0, float arg1, int arg2) { } @Override public void onPageScrollStateChanged(int arg0) { } }); } @Override public void onClick(View v) { switch (v.getId()) { case R.id.btnPreMonth: mViewPager.setCurrentItem(mViewPager.getCurrentItem() - 1); break; case R.id.btnNextMonth: mViewPager.setCurrentItem(mViewPager.getCurrentItem() + 1); break; case R.id.btnClose: finish(); break; default: break; } } @Override public void clickDate(CustomDate date) { } @Override public void changeDate(CustomDate date) { monthText.setText(date.month + "月"); } /** * 计算方向 * * @param arg0 */ private void measureDirection(int arg0) { if (arg0 > mCurrentIndex) { mDirection = SildeDirection.RIGHT; } else if (arg0 < mCurrentIndex) { mDirection = SildeDirection.LEFT; } mCurrentIndex = arg0; } // 更新日历视图 private void updateCalendarView(int arg0) { mShowViews = adapter.getAllItems(); if (mDirection == SildeDirection.RIGHT) { mShowViews[arg0 % mShowViews.length].rightSlide(); } else if (mDirection == SildeDirection.LEFT) { mShowViews[arg0 % mShowViews.length].leftSlide(); } mDirection = SildeDirection.NO_SILDE; } }用到的资源：
/CustomCalendarView/res/values/color.xml
<?xml version="1.0" encoding="utf-8"?><resources> <color name="white">#ffffff</color> <color name="canlendar_text_color">#323232</color></resources>
<?xml version="1.0" encoding="utf-8"?><resources> <string name="app_name">CustomCalendarView</string> <string name="hello_world">Hello world!</string> <string name="action_settings">Settings</string> <string name="sunday">日</string> <string name="monday">一</string> <string name="thesday">二</string> <string name="wednesday">三</string> <string name="thursday">四</string> <string name="friday">五</string> <string name="saturday">六</string> </resources>/CustomCalendarView/res/values/styles.xml
<resources> <!-- Base application theme, dependent on API level. This theme is replaced by AppBaseTheme from res/values-vXX/styles.xml on newer devices. --> <style name="AppBaseTheme" parent="android:Theme.Light"> <!-- Theme customizations available in newer API levels can go in res/values-vXX/styles.xml, while customizations related to backward-compatibility can go here. --> </style> <!-- Application theme. --> <style name="AppTheme" parent="AppBaseTheme"> <!-- All customizations that are NOT specific to a particular API-level can go here. --> </style> <style name="dateStyle"> <item name="android:layout_width">fill_parent</item> <item name="android:layout_height">fill_parent</item> <item name="android:layout_weight">1</item> <item name="android:gravity">center</item> <item name="android:textSize">16sp</item> </style></resources>源码下载：http://download.csdn.net/detail/wwj_748/8312233
给我老师的人工智能教程打call！http://blog.csdn.net/jiangjunshow
