From 707888f320706d1c4d0fb35b60dc33d774ea83c7 Mon Sep 17 00:00:00 2001 From: p6zpjanrb <1157949412@qq.com> Date: Thu, 14 Dec 2023 10:04:09 +0800 Subject: [PATCH] Update DateTimePicker.java --- src/net/micode/notes/ui/DateTimePicker.java | 44 +++++++++++++++------ 1 file changed, 32 insertions(+), 12 deletions(-) diff --git a/src/net/micode/notes/ui/DateTimePicker.java b/src/net/micode/notes/ui/DateTimePicker.java index 496b0cd..5432596 100644 --- a/src/net/micode/notes/ui/DateTimePicker.java +++ b/src/net/micode/notes/ui/DateTimePicker.java @@ -29,7 +29,8 @@ import android.widget.FrameLayout; import android.widget.NumberPicker; public class DateTimePicker extends FrameLayout { - +//FrameLayout是布局模板之一 +//所有的子元素全部在屏幕的右上方 private static final boolean DEFAULT_ENABLE_STATE = true; private static final int HOURS_IN_HALF_DAY = 12; @@ -45,12 +46,15 @@ public class DateTimePicker extends FrameLayout { private static final int MINUT_SPINNER_MAX_VAL = 59; private static final int AMPM_SPINNER_MIN_VAL = 0; private static final int AMPM_SPINNER_MAX_VAL = 1; - + //初始化控件 private final NumberPicker mDateSpinner; private final NumberPicker mHourSpinner; private final NumberPicker mMinuteSpinner; private final NumberPicker mAmPmSpinner; + //NumberPicker是数字选择器 + //这里定义的四个变量全部是在设置闹钟时需要选择的变量（如日期、时、分、上午或者下午） private Calendar mDate; + //定义了Calendar类型的变量mDate，用于操作时间 private String[] mDateDisplayValues = new String[DAYS_IN_ALL_WEEK]; @@ -71,41 +75,49 @@ public class DateTimePicker extends FrameLayout { updateDateControl(); onDateTimeChanged(); } - }; + };//OnValueChangeListener，这是时间改变监听器，这里主要是对日期的监听 + //将现在日期的值传递给mDate；updateDateControl是同步操作 private NumberPicker.OnValueChangeListener mOnHourChangedListener = new NumberPicker.OnValueChangeListener() { - @Override + //这里是对小时（Hour） 的监听 + @Override public void onValueChange(NumberPicker picker, int oldVal, int newVal) { boolean isDateChanged = false; Calendar cal = Calendar.getInstance(); + //声明一个Calendar的变量cal，便于后续的操作 if (!mIs24HourView) { if (!mIsAm && oldVal == HOURS_IN_HALF_DAY - 1 && newVal == HOURS_IN_HALF_DAY) { cal.setTimeInMillis(mDate.getTimeInMillis()); cal.add(Calendar.DAY_OF_YEAR, 1); isDateChanged = true; + //这里是对于12小时制时，晚上11点和12点交替时对日期的更改 } else if (mIsAm && oldVal == HOURS_IN_HALF_DAY && newVal == HOURS_IN_HALF_DAY - 1) { cal.setTimeInMillis(mDate.getTimeInMillis()); cal.add(Calendar.DAY_OF_YEAR, -1); isDateChanged = true; } + //这里是对于12小时制时，凌晨11点和12点交替时对日期的更改 if (oldVal == HOURS_IN_HALF_DAY - 1 && newVal == HOURS_IN_HALF_DAY || oldVal == HOURS_IN_HALF_DAY && newVal == HOURS_IN_HALF_DAY - 1) { mIsAm = !mIsAm; updateAmPmControl(); - } + }//这里是对于12小时制时，中午11点和12点交替时对AM和PM的更改 } else { if (oldVal == HOURS_IN_ALL_DAY - 1 && newVal == 0) { cal.setTimeInMillis(mDate.getTimeInMillis()); cal.add(Calendar.DAY_OF_YEAR, 1); isDateChanged = true; + //这里是对于24小时制时，晚上11点和12点交替时对日期的更改 } else if (oldVal == 0 && newVal == HOURS_IN_ALL_DAY - 1) { cal.setTimeInMillis(mDate.getTimeInMillis()); cal.add(Calendar.DAY_OF_YEAR, -1); isDateChanged = true; } - } + }//这里是对于12小时制时，凌晨11点和12点交替时对日期的更改 int newHour = mHourSpinner.getValue() % HOURS_IN_HALF_DAY + (mIsAm ? 0 : HOURS_IN_HALF_DAY); + //通过数字选择器对newHour的赋值 mDate.set(Calendar.HOUR_OF_DAY, newHour); + //通过set函数将新的Hour值传给mDate onDateTimeChanged(); if (isDateChanged) { setCurrentYear(cal.get(Calendar.YEAR)); @@ -117,15 +129,19 @@ public class DateTimePicker extends FrameLayout { private NumberPicker.OnValueChangeListener mOnMinuteChangedListener = new NumberPicker.OnValueChangeListener() { @Override + //对分钟（Minute）改变的监听 public void onValueChange(NumberPicker picker, int oldVal, int newVal) { int minValue = mMinuteSpinner.getMinValue(); int maxValue = mMinuteSpinner.getMaxValue(); int offset = 0; + //设置offset，作为小时改变的一个记录数据 if (oldVal == maxValue && newVal == minValue) { offset += 1; } else if (oldVal == minValue && newVal == maxValue) { offset -= 1; } + //如果原值为59，新值为0，则offset加1 + //如果原值为0，新值为59，则offset减1 if (offset != 0) { mDate.add(Calendar.HOUR_OF_DAY, offset); mHourSpinner.setValue(getCurrentHour()); @@ -145,6 +161,7 @@ public class DateTimePicker extends FrameLayout { }; private NumberPicker.OnValueChangeListener mOnAmPmChangedListener = new NumberPicker.OnValueChangeListener() { + //对AM和PM的监听 @Override public void onValueChange(NumberPicker picker, int oldVal, int newVal) { mIsAm = !mIsAm; @@ -165,19 +182,22 @@ public class DateTimePicker extends FrameLayout { public DateTimePicker(Context context) { this(context, System.currentTimeMillis()); - } + }//通过对数据库的访问，获取当前的系统时间 public DateTimePicker(Context context, long date) { this(context, date, DateFormat.is24HourFormat(context)); - } + }//上面函数的得到的是一个天文数字（1970至今的秒数），需要DateFormat将其变得有意义 public DateTimePicker(Context context, long date, boolean is24HourView) { super(context); + //获取系统时间 mDate = Calendar.getInstance(); mInitialising = true; mIsAm = getCurrentHourOfDay() >= HOURS_IN_HALF_DAY; inflate(context, R.layout.datetime_picker, this); - + //如果当前Activity里用到别的layout，比如对话框layout + //还要设置这个layout上的其他组件的内容，就必须用inflate()方法先将对话框的layout找出来 + //然后再用findViewById()找到它上面的其它组件 mDateSpinner = (NumberPicker) findViewById(R.id.date); mDateSpinner.setMinValue(DATE_SPINNER_MIN_VAL); mDateSpinner.setMaxValue(DATE_SPINNER_MAX_VAL); @@ -269,7 +289,7 @@ public class DateTimePicker extends FrameLayout { setCurrentDay(dayOfMonth); setCurrentHour(hourOfDay); setCurrentMinute(minute); - } + }//实现函数功能——设置当前的时间，参数是各详细的变量 /** * Get current year @@ -432,7 +452,7 @@ public class DateTimePicker extends FrameLayout { updateHourControl(); setCurrentHour(hour); updateAmPmControl(); - } + }//对于星期几的算法 private void updateDateControl() { Calendar cal = Calendar.getInstance(); @@ -446,7 +466,7 @@ public class DateTimePicker extends FrameLayout { mDateSpinner.setDisplayedValues(mDateDisplayValues); mDateSpinner.setValue(DAYS_IN_ALL_WEEK / 2); mDateSpinner.invalidate(); - } + }//对于上下午操作的算法 private void updateAmPmControl() { if (mIs24HourView) {