| /* |
| * Copyright (C) 2007 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.util; |
| |
| import java.util.Calendar; |
| |
| /** |
| * Helps answer common questions that come up when displaying a month in a |
| * 6 row calendar grid format. |
| * |
| * Not thread safe. |
| */ |
| public class MonthDisplayHelper { |
| |
| // display pref |
| private final int mWeekStartDay; |
| |
| // holds current month, year, helps compute display |
| private Calendar mCalendar; |
| |
| // cached computed stuff that helps with display |
| private int mNumDaysInMonth; |
| private int mNumDaysInPrevMonth; |
| private int mOffset; |
| |
| |
| /** |
| * @param year The year. |
| * @param month The month. |
| * @param weekStartDay What day of the week the week should start. |
| */ |
| public MonthDisplayHelper(int year, int month, int weekStartDay) { |
| |
| if (weekStartDay < Calendar.SUNDAY || weekStartDay > Calendar.SATURDAY) { |
| throw new IllegalArgumentException(); |
| } |
| mWeekStartDay = weekStartDay; |
| |
| mCalendar = Calendar.getInstance(); |
| mCalendar.set(Calendar.YEAR, year); |
| mCalendar.set(Calendar.MONTH, month); |
| mCalendar.set(Calendar.DAY_OF_MONTH, 1); |
| mCalendar.set(Calendar.HOUR_OF_DAY, 0); |
| mCalendar.set(Calendar.MINUTE, 0); |
| mCalendar.set(Calendar.SECOND, 0); |
| mCalendar.getTimeInMillis(); |
| |
| recalculate(); |
| } |
| |
| |
| public MonthDisplayHelper(int year, int month) { |
| this(year, month, Calendar.SUNDAY); |
| } |
| |
| |
| public int getYear() { |
| return mCalendar.get(Calendar.YEAR); |
| } |
| |
| public int getMonth() { |
| return mCalendar.get(Calendar.MONTH); |
| } |
| |
| |
| public int getWeekStartDay() { |
| return mWeekStartDay; |
| } |
| |
| /** |
| * @return The first day of the month using a constants such as |
| * {@link java.util.Calendar#SUNDAY}. |
| */ |
| public int getFirstDayOfMonth() { |
| return mCalendar.get(Calendar.DAY_OF_WEEK); |
| } |
| |
| /** |
| * @return The number of days in the month. |
| */ |
| public int getNumberOfDaysInMonth() { |
| return mNumDaysInMonth; |
| } |
| |
| |
| /** |
| * @return The offset from displaying everything starting on the very first |
| * box. For example, if the calendar is set to display the first day of |
| * the week as Sunday, and the month starts on a Wednesday, the offset is 3. |
| */ |
| public int getOffset() { |
| return mOffset; |
| } |
| |
| |
| /** |
| * @param row Which row (0-5). |
| * @return the digits of the month to display in one |
| * of the 6 rows of a calendar month display. |
| */ |
| public int[] getDigitsForRow(int row) { |
| if (row < 0 || row > 5) { |
| throw new IllegalArgumentException("row " + row |
| + " out of range (0-5)"); |
| } |
| |
| int [] result = new int[7]; |
| for (int column = 0; column < 7; column++) { |
| result[column] = getDayAt(row, column); |
| } |
| |
| return result; |
| } |
| |
| /** |
| * @param row The row, 0-5, starting from the top. |
| * @param column The column, 0-6, starting from the left. |
| * @return The day at a particular row, column |
| */ |
| public int getDayAt(int row, int column) { |
| |
| if (row == 0 && column < mOffset) { |
| return mNumDaysInPrevMonth + column - mOffset + 1; |
| } |
| |
| int day = 7 * row + column - mOffset + 1; |
| |
| return (day > mNumDaysInMonth) ? |
| day - mNumDaysInMonth : day; |
| } |
| |
| /** |
| * @return Which row day is in. |
| */ |
| public int getRowOf(int day) { |
| return (day + mOffset - 1) / 7; |
| } |
| |
| /** |
| * @return Which column day is in. |
| */ |
| public int getColumnOf(int day) { |
| return (day + mOffset - 1) % 7; |
| } |
| |
| /** |
| * Decrement the month. |
| */ |
| public void previousMonth() { |
| mCalendar.add(Calendar.MONTH, -1); |
| recalculate(); |
| } |
| |
| /** |
| * Increment the month. |
| */ |
| public void nextMonth() { |
| mCalendar.add(Calendar.MONTH, 1); |
| recalculate(); |
| } |
| |
| /** |
| * @return Whether the row and column fall within the month. |
| */ |
| public boolean isWithinCurrentMonth(int row, int column) { |
| |
| if (row < 0 || column < 0 || row > 5 || column > 6) { |
| return false; |
| } |
| |
| if (row == 0 && column < mOffset) { |
| return false; |
| } |
| |
| int day = 7 * row + column - mOffset + 1; |
| if (day > mNumDaysInMonth) { |
| return false; |
| } |
| return true; |
| } |
| |
| |
| // helper method that recalculates cached values based on current month / year |
| private void recalculate() { |
| |
| mNumDaysInMonth = mCalendar.getActualMaximum(Calendar.DAY_OF_MONTH); |
| |
| mCalendar.add(Calendar.MONTH, -1); |
| mNumDaysInPrevMonth = mCalendar.getActualMaximum(Calendar.DAY_OF_MONTH); |
| mCalendar.add(Calendar.MONTH, 1); |
| |
| int firstDayOfMonth = getFirstDayOfMonth(); |
| int offset = firstDayOfMonth - mWeekStartDay; |
| if (offset < 0) { |
| offset += 7; |
| } |
| mOffset = offset; |
| } |
| } |