修改UI/DateTimePicker部分

MiNote/app/src/main/java/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;
@@ -45,13 +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];
 
     private boolean mIsAm;
@@ -64,6 +67,7 @@ public class DateTimePicker extends FrameLayout {
 
     private OnDateTimeChangedListener mOnDateTimeChangedListener;
 
+    //OnValueChangeListener，这是时间改变监听器，这里主要是对日期的监听
     private NumberPicker.OnValueChangeListener mOnDateChangedListener = new NumberPicker.OnValueChangeListener() {
         @Override
         public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
@@ -72,40 +76,52 @@ public class DateTimePicker extends FrameLayout {
             onDateTimeChanged();
         }
     };
+    //将现在日期的值传递给mDate；updateDateControl是同步操作
 
     private NumberPicker.OnValueChangeListener mOnHourChangedListener = new NumberPicker.OnValueChangeListener() {
+        //这里是对 小时（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;
-                } else if (mIsAm && oldVal == HOURS_IN_HALF_DAY && newVal == HOURS_IN_HALF_DAY - 1) {
+                }
+                //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();
                 }
-            } else {
+                //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;
-                } else if (oldVal == 0 && newVal == HOURS_IN_ALL_DAY - 1) {
+                }
+                //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));
@@ -116,16 +132,20 @@ public class DateTimePicker extends FrameLayout {
     };
 
     private NumberPicker.OnValueChangeListener mOnMinuteChangedListener = new NumberPicker.OnValueChangeListener() {
+        //这里是对 分钟（Minute）改变的监听
         @Override
         public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
             int minValue = mMinuteSpinner.getMinValue();
             int maxValue = mMinuteSpinner.getMaxValue();
-            int offset = 0;
+            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) {
+            }
+            //如果原值为59，新值为0，则offset加1
+            else if (oldVal == minValue && newVal == maxValue) {
                 offset -= 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 +165,7 @@ 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;
@@ -166,18 +187,21 @@ 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);
@@ -270,6 +294,7 @@ public class DateTimePicker extends FrameLayout {
         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
@@ -447,15 +472,18 @@ public class DateTimePicker extends FrameLayout {
         mDateSpinner.setValue(DAYS_IN_ALL_WEEK / 2);
         mDateSpinner.invalidate();
     }
+    // 对于星期几的算法
 
     private void updateAmPmControl() {
         if (mIs24HourView) {
             mAmPmSpinner.setVisibility(View.GONE);
-        } else {
+        }
+        else {
             int index = mIsAm ? Calendar.AM : Calendar.PM;
             mAmPmSpinner.setValue(index);
             mAmPmSpinner.setVisibility(View.VISIBLE);
         }
+        // 对于上下午操作的算法
     }
 
     private void updateHourControl() {
@@ -467,6 +495,7 @@ public class DateTimePicker extends FrameLayout {
             mHourSpinner.setMaxValue(HOUR_SPINNER_MAX_VAL_12_HOUR_VIEW);
         }
     }
+    // 对与小时的算法
 
     /**
      * Set the callback that indicates the 'Set' button has been pressed.