diff --git a/app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java b/app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java index f221202..6301647 100644 --- a/app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java +++ b/app/src/main/java/net/micode/notes/ui/AlarmInitReceiver.java @@ -34,19 +34,22 @@ public class AlarmInitReceiver extends BroadcastReceiver { NoteColumns.ID, NoteColumns.ALERTED_DATE }; - +//对数据库的操作,调用标签ID和闹钟时间 private static final int COLUMN_ID = 0; private static final int COLUMN_ALERTED_DATE = 1; @Override public void onReceive(Context context, Intent intent) { long currentDate = System.currentTimeMillis(); + //System.currentTimeMillis()产生一个当前的毫秒 + //这个毫秒就是自1970年1月1日0时起的毫秒数 Cursor c = context.getContentResolver().query(Notes.CONTENT_NOTE_URI, PROJECTION, NoteColumns.ALERTED_DATE + ">? AND " + NoteColumns.TYPE + "=" + Notes.TYPE_NOTE, new String[] { String.valueOf(currentDate) }, + //将long变量currentData转化为字符串 null); - +//Cursor在这里的作用是通过查找数据库中的标签内容,找到和当前系统时间相等的标签 if (c != null) { if (c.moveToFirst()) { do { @@ -62,4 +65,7 @@ public class AlarmInitReceiver extends BroadcastReceiver { c.close(); } } + //然而通过网上查找资料发现,对于闹钟机制的启动,通常需要上面的几个步骤 + //如新建Intent、PendingIntrnt以及AlarmManger等 + //这里就是根据数据库里的闹钟时间创建一个闹钟机制 } diff --git a/app/src/main/java/net/micode/notes/ui/DateTimePicker.java b/app/src/main/java/net/micode/notes/ui/DateTimePicker.java index 496b0cd..45735e7 100644 --- a/app/src/main/java/net/micode/notes/ui/DateTimePicker.java +++ b/app/src/main/java/net/micode/notes/ui/DateTimePicker.java @@ -29,6 +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元素的右上方 private static final boolean DEFAULT_ENABLE_STATE = true; @@ -45,13 +47,15 @@ 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]; private boolean mIsAm; @@ -71,23 +75,28 @@ public class DateTimePicker extends FrameLayout { updateDateControl(); onDateTimeChanged(); } - }; + };//OnValueChangeListener,这是时间改变监听器,这里主要是对日期监听 + //将现在的日期的值传递给mDate,updateDateControl是同步操作 private NumberPicker.OnValueChangeListener mOnHourChangedListener = new NumberPicker.OnValueChangeListener() { + //这里是对小时的监听 @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显示制时,凌晨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,中午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; @@ -98,12 +107,13 @@ public class DateTimePicker extends FrameLayout { 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 (oldVal == 0 && newVal == HOURS_IN_ALL_DAY - 1) { cal.setTimeInMillis(mDate.getTimeInMillis()); cal.add(Calendar.DAY_OF_YEAR, -1); isDateChanged = true; } - } + }//这里是对弈24 int newHour = mHourSpinner.getValue() % HOURS_IN_HALF_DAY + (mIsAm ? 0 : HOURS_IN_HALF_DAY); mDate.set(Calendar.HOUR_OF_DAY, newHour); onDateTimeChanged();