Java tutorial
/* * Copyright (C) 2013 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 com.philliphsu.bottomsheetpickers.date; import android.content.Context; import android.os.Bundle; import android.os.Parcelable; import android.support.v4.view.PagerAdapter; import android.util.SparseArray; import android.view.View; import android.view.ViewGroup; import android.view.ViewGroup.LayoutParams; import com.philliphsu.bottomsheetpickers.Utils; import com.philliphsu.bottomsheetpickers.date.MonthView.OnDayClickListener; import java.util.ArrayList; import java.util.Calendar; import java.util.HashMap; import static android.view.ViewGroup.LayoutParams.MATCH_PARENT; /** * An adapter for a pager of {@link MonthView} items. */ class PagingMonthAdapter extends PagerAdapter implements OnDayClickListener { private static final String TAG = "SimpleMonthAdapter"; private static final String KEY_POSITIONS = "positions"; private static final String KEY_MONTH_YEAR_TITLES = "month_year_titles"; private final Context mContext; private final boolean mThemeDark; private final int mAccentColor; private final SparseArray<String> mMonthYearTitles = new SparseArray<>(); private final ArrayList<MonthView> mMonthViews = new ArrayList<>(); protected final DatePickerController mController; private CalendarDay mSelectedDay; private MonthView mCurrentPrimaryItem; protected static int WEEK_7_OVERHANG_HEIGHT = 7; protected static final int MONTHS_IN_YEAR = 12; public PagingMonthAdapter(Context context, DatePickerController controller) { this(context, controller, false); } public PagingMonthAdapter(Context context, DatePickerController controller, boolean themeDark) { this(context, controller, themeDark, Utils.getThemeAccentColor(context)); } public PagingMonthAdapter(Context context, DatePickerController controller, boolean themeDark, int accentColor) { mContext = context; mController = controller; mThemeDark = themeDark; mAccentColor = accentColor; init(); setSelectedDay(mController.getSelectedDay()); } /** * Updates the selected day and related parameters. * * @param day The day to highlight */ public void setSelectedDay(CalendarDay day) { mSelectedDay = day; notifyDataSetChanged(); // This won't refresh our views! // In the ListView-based day picker, notifyDataSetChanged() would have refreshed this // adapter's contents, so instantiateItem() is called again on the entire data set. // This would have called each MonthView's setMonthParams() with the correct value for the // selectedDay (either -1 or the actual selected day if the selection is in that month) // and invalidate(). However, PagerAdapter's implementation of notifyDataSetChanged() // won't do all this for us, so we have to manually do it. for (MonthView mv : mMonthViews) { mv.setSelectedDay(mv == mCurrentPrimaryItem ? day.day : -1); mv.invalidate(); } } public CalendarDay getSelectedDay() { return mSelectedDay; } /** * Set up the gesture detector and selected time */ protected void init() { mSelectedDay = new CalendarDay(System.currentTimeMillis()); } @Override public int getCount() { final Calendar minDate = mController.getMinDate(); final Calendar maxDate = mController.getMaxDate(); final int minMonth = minDate == null ? 0 : minDate.get(Calendar.MONTH); // The number of months remaining in minDate's year, from minMonth forward. int monthsInMinYear = MONTHS_IN_YEAR - minMonth; // The number of months in maxDate's year, up to maxDate's month. // From Calendar.JANUARY (0) forward. int monthsInMaxYear = maxDate == null ? MONTHS_IN_YEAR : maxDate.get(Calendar.MONTH) + 1; int count = monthsInMinYear + monthsInMaxYear; // Add the number of months in between the min and max dates. // Subtract 2 from the year range because we already counted the min and max years. // Add 1 to get the total number of years in the year range. // e.g. There are 11 years in the range [2016, 2026]. // => net difference = -1 count += (mController.getMaxYear() - mController.getMinYear() - 1) * MONTHS_IN_YEAR; return count; } @Override public boolean isViewFromObject(View view, Object object) { return view == object; } @Override public Object instantiateItem(ViewGroup container, int position) { MonthView v; HashMap<String, Integer> drawingParams = null; v = createMonthView(mContext, mThemeDark, mAccentColor); // Set up the new view v.setClickable(true); v.setOnDayClickListener(this); if (drawingParams == null) { drawingParams = new HashMap<>(); } drawingParams.clear(); final int month = getMonth(position); final int year = getYear(position); int selectedDay = -1; if (isSelectedDayInMonth(year, month)) { selectedDay = mSelectedDay.day; } // Invokes requestLayout() to ensure that the recycled view is set with the appropriate // height/number of weeks before being displayed. v.reuse(); drawingParams.put(MonthView.VIEW_PARAMS_SELECTED_DAY, selectedDay); drawingParams.put(MonthView.VIEW_PARAMS_YEAR, year); drawingParams.put(MonthView.VIEW_PARAMS_MONTH, month); drawingParams.put(MonthView.VIEW_PARAMS_WEEK_START, mController.getFirstDayOfWeek()); v.setMonthParams(drawingParams); v.invalidate(); container.addView(v, new LayoutParams(MATCH_PARENT, MATCH_PARENT)); mMonthYearTitles.append(position, v.getMonthAndYearString()); mMonthViews.add(v); return v; } @Override public void destroyItem(ViewGroup container, int position, Object object) { container.removeView((View) object); mMonthYearTitles.delete(position); mMonthViews.remove(object); } @Override public void setPrimaryItem(ViewGroup container, int position, Object object) { mCurrentPrimaryItem = (MonthView) object; } @Override public CharSequence getPageTitle(int position) { return mMonthYearTitles.get(position); } @Override public Parcelable saveState() { Bundle state = null; final int size = mMonthYearTitles.size(); if (size > 0) { state = new Bundle(); String[] titles = new String[size]; int[] positions = new int[size]; for (int i = 0; i < size; i++) { titles[i] = mMonthYearTitles.valueAt(i); positions[i] = mMonthYearTitles.keyAt(i); } state.putStringArray(KEY_MONTH_YEAR_TITLES, titles); state.putIntArray(KEY_POSITIONS, positions); } return state; } @Override public void restoreState(Parcelable state, ClassLoader loader) { if (state != null) { Bundle bundle = (Bundle) state; bundle.setClassLoader(loader); String[] titles = bundle.getStringArray(KEY_MONTH_YEAR_TITLES); int[] positions = bundle.getIntArray(KEY_POSITIONS); mMonthYearTitles.clear(); if (titles != null && positions != null) { // Both arrays should be the same size, so use either length. for (int i = 0; i < titles.length; i++) { mMonthYearTitles.append(positions[i], titles[i]); } } } } public MonthView createMonthView(Context context) { return createMonthView(context, false); } public MonthView createMonthView(Context context, boolean themeDark) { return createMonthView(context, themeDark, mAccentColor); } public MonthView createMonthView(Context context, boolean themeDark, int accentColor) { final MonthView monthView = new SimpleMonthView(context); monthView.setDatePickerController(mController); monthView.setTheme(context, themeDark); monthView.setTodayNumberColor(accentColor); monthView.setSelectedCirclePaintColor(accentColor); return monthView; } private boolean isSelectedDayInMonth(int year, int month) { return mSelectedDay.year == year && mSelectedDay.month == month; } @Override public void onDayClick(MonthView view, CalendarDay day) { if (day != null) { onDayTapped(day); } } /** * Maintains the same hour/min/sec but moves the day to the tapped day. * * @param day The day that was tapped */ protected void onDayTapped(CalendarDay day) { mController.tryVibrate(); mController.onDayOfMonthSelected(day.year, day.month, day.day); setSelectedDay(day); } /** * Returns the month (0 - 11) displayed at this position. */ final int getMonth(int position) { return (position + getMonthOffset()) % MONTHS_IN_YEAR; } /** * Returns the year displayed at this position. */ final int getYear(int position) { return (position + getMonthOffset()) / MONTHS_IN_YEAR + mController.getMinYear(); } /** * @return The page position at which the given day is located. */ final int getPosition(CalendarDay day) { int positionOfYear = MONTHS_IN_YEAR * (day.year - mController.getMinYear()) - getMonthOffset(); return positionOfYear + day.month; } private int getMonthOffset() { Calendar minDate = mController.getMinDate(); return minDate == null ? 0 : minDate.get(Calendar.MONTH); } }