Android原生的CalendarView根本无法满足我们日常开发的需要，在开发吾记APP的过程中，我觉得需要来一款高性能且美观简洁的日历控件，觉得魅族的日历风格十分适合，于是打算撸一款。
github地址：https://github.com/huanghaibin-dev/CalendarView
compile 'com.haibin:calendarview:1.0.2'
先上效果图：
动手之前我们需要分析一下魅族是怎么设计如此高性能的日历的，我们打开开发者选项中的显示布局边界：
好吧，一开始我以为日历界面是ViewPager+RecyclerView的，但是这么一看明显就不是了，如果是RecyclerView，那么我们假设每个月的卡片都有5*7=35个item，每个item根布局是RelativeLayout+3个TextView，我们大概估算一下日历初始化时要加载的控件：
3个ViewPager的item * 35个RecyclerView的Item * 4（每个item的控件数） + 8 （星期栏）= 420+
我的天，这可不能这么干，明显性能大打折扣，我们再来看看月份控件：
好吧，这里看上去就是ViewPager+RecyclerView来做的，每个RecyclerView的item都只是一个控件，里面绘制了文本 ，这里大概就分析清楚了。
我们采取折中的方式，日历界面和月份卡界面均采用ViewPager+RecyclerView的方式，不同的是所有的item我们都采用自定义ViewCanvas绘制的方式来做，这样性能虽然比不上魅族，但速度体验基本差不多，下面先看日历界面的item代码：只需要绘制3个文本即可
public class CellView extends View {
private int mDay = 20;
private String mLunar;
private String mScheme;
private Paint mDayPaint = new Paint();
private Paint mLunarPaint = new Paint();
private Paint mSchemePaint = new Paint();
private Paint mCirclePaint = new Paint();
private int mRadius;
private int mCirclePadding;
private int mCircleColor;
public CellView(Context context) {
this(context, null);
}
public CellView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
mDayPaint.setAntiAlias(true);
mDayPaint.setColor(Color.BLACK);
mDayPaint.setFakeBoldText(true);
mDayPaint.setTextAlign(Paint.Align.CENTER);
mLunarPaint.setAntiAlias(true);
mLunarPaint.setColor(Color.GRAY);
mLunarPaint.setTextAlign(Paint.Align.CENTER);
mSchemePaint.setAntiAlias(true);
mSchemePaint.setColor(Color.WHITE);
mSchemePaint.setFakeBoldText(true);
mSchemePaint.setTextAlign(Paint.Align.CENTER);
mCirclePaint.setAntiAlias(true);
mCirclePaint.setStyle(Paint.Style.FILL);
TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.CellView);
mDayPaint.setTextSize(array.getDimensionPixelSize(R.styleable.CellView_cell_day_text_size, 18));
mLunarPaint.setTextSize(array.getDimensionPixelSize(R.styleable.CellView_cell_lunar_text_size, 12));
mRadius = (int) array.getDimension(R.styleable.CellView_cell_scheme_radius, 8);
mSchemePaint.setTextSize(array.getDimensionPixelSize(R.styleable.CellView_cell_scheme_text_size, 6));
mCirclePadding = array.getDimensionPixelSize(R.styleable.CellView_cell_circle_padding, 4);
mCirclePaint.setColor(array.getColor(R.styleable.CellView_cell_circle_color, 0xff16BB7F));
array.recycle();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int width = getWidth();
int height = getHeight();
int w = (width - getPaddingLeft() - getPaddingRight());
int h = (height - getPaddingTop() - getPaddingBottom()) / 4;
canvas.drawText(String.valueOf(mDay), w / 2, 2 * h + getPaddingTop(), mDayPaint);
canvas.drawText(mLunar, w / 2, 4 * h + getPaddingTop(), mLunarPaint);
if (!TextUtils.isEmpty(mScheme)) {
canvas.drawCircle(w / 2 + mCirclePadding + mDayPaint.getTextSize(), getPaddingTop() + h, mRadius, mCirclePaint);
canvas.drawText(mScheme, w / 2 + mCirclePadding + mDayPaint.getTextSize(), getPaddingTop() + mRadius / 2 + h, mSchemePaint);
}
}
/**
* 初始化日历
* @param day 天
* @param lunar 农历
* @param scheme 事件标记
*/
void init(int day, String lunar, String scheme) {
this.mDay = day;
this.mLunar = lunar;
this.mScheme = scheme;
}
void setTextColor(int textColor) {
mDayPaint.setColor(textColor);
mLunarPaint.setColor(textColor);
}
void setCircleColor(int circleColor) {
mCirclePaint.setColor(circleColor);
invalidate();
}
}
月份卡自定义View
public class MonthView extends View {
private int mDiff;//第一天偏离周日多少天
private int mCount;//总数
private int mLastCount;//最后一行的天数
private int mLine;//多少行
private Paint mPaint = new Paint();
private Paint mSchemePaint = new Paint();
private List<Calendar> mSchemes;
private Calendar mCalendar;
public MonthView(Context context) {
this(context, null);
}
public MonthView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
mPaint.setAntiAlias(true);
mPaint.setTextAlign(Paint.Align.CENTER);
mSchemePaint.setAntiAlias(true);
mSchemePaint.setTextAlign(Paint.Align.CENTER);
TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.MonthView);
mPaint.setTextSize(array.getDimensionPixelSize(R.styleable.MonthView_month_view_text_size, 12));
mSchemePaint.setTextSize(array.getDimensionPixelSize(R.styleable.MonthView_month_view_text_size, 12));
mPaint.setColor(array.getColor(R.styleable.MonthView_month_view_text_color, Color.BLACK));
mSchemePaint.setColor(array.getColor(R.styleable.MonthView_month_view_remark_color, Color.RED));
array.recycle();
measureLine();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int width = getWidth();
int height = getHeight();
int pLeft = getPaddingLeft();
int w = (width - getPaddingLeft() - getPaddingRight()) / 7;
int h = (height - getPaddingTop() - getPaddingBottom()) / 6;
int d = 0;
for (int i = 0; i < mLine; i++) {
if (i == 0) {//第一行
for (int j = 0; j < (7 - mDiff); j++) {
++d;
canvas.drawText(String.valueOf(j + 1), mDiff * w + j * w + pLeft + w / 2, h, isScheme(d) ? mSchemePaint : mPaint);
}
} else if (i == mLine - 1 && mLastCount != 0) {
int first = mCount - mLastCount + 1;
for (int j = 0; j < mLastCount; j++) {
++d;
canvas.drawText(String.valueOf(first), j * w + pLeft + w / 2, (i + 1) * h, isScheme(d) ? mSchemePaint : mPaint);
++first;
}
} else {
int first = i * 7 - mDiff + 1;
for (int j = 0; j < 7; j++) {
++d;
canvas.drawText(String.valueOf(first), j * w + pLeft + w / 2, (i + 1) * h, isScheme(d) ? mSchemePaint : mPaint);
++first;
}
}
}
}
/**
* 计算行数
*/
private void measureLine() {
int offset = mCount - (7 - mDiff);
mLine = 1 + (offset % 7 == 0 ? 0 : 1) + offset / 7;
mLastCount = offset % 7;
}
/**
* 初始化月份卡
* @param mDiff 偏离天数
* @param mCount 当月总天数
* @param mYear 哪一年
* @param mMonth 哪一月
*/
void init(int mDiff, int mCount, int mYear, int mMonth) {
this.mDiff = mDiff;
this.mCount = mCount;
mCalendar = new Calendar();
mCalendar.setYear(mYear);
mCalendar.setMonth(mMonth);
measureLine();
invalidate();
}
void setSchemes(List<Calendar> mSchemes) {
this.mSchemes = mSchemes;
}
void setSchemeColor(int schemeColor) {
if (schemeColor != 0)
mSchemePaint.setColor(schemeColor);
if(schemeColor == 0xff30393E)
mSchemePaint.setColor(Color.RED);
}
private boolean isScheme(int day) {
if (mSchemes == null || mSchemes.size() == 0)
return false;
mCalendar.setDay(day);
return mSchemes.contains(mCalendar);
}
}
其它代码没有什么难度，日历算法是github上找的，更多详情请看仓库地址：https://github.com/huanghaibin-dev/CalendarView