Week picker for android

content/public/android/java/src/org/chromium/content/browser/input/WeekPicker.java

Index: content/public/android/java/src/org/chromium/content/browser/input/WeekPicker.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/WeekPicker.java b/content/public/android/java/src/org/chromium/content/browser/input/WeekPicker.java
new file mode 100644
index 0000000000000000000000000000000000000000..e11c7c7f319acdb3779cc2591c821d6af1ab62c9
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+++ b/content/public/android/java/src/org/chromium/content/browser/input/WeekPicker.java
@@ -0,0 +1,130 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.content.browser.input;
+
+import android.content.Context;
+
+import java.util.Calendar;
+
+import org.chromium.content.R;
+
+// This class is heavily based on android.widget.DatePicker.
+public class WeekPicker extends TwoFieldDatePicker {
+
+    public WeekPicker(Context context, long minValue, long maxValue) {
+        super(context, minValue, maxValue);
+
+        getPositionInYearSpinner().setContentDescription(
+                getResources().getString(R.string.accessibility_date_picker_week));
+
+        // initialize to current date
+        Calendar cal = Calendar.getInstance();
+        cal.setFirstDayOfWeek(Calendar.MONDAY);
+        cal.setMinimalDaysInFirstWeek(4);
+        cal.setTimeInMillis(System.currentTimeMillis());
+        init(getISOWeekYearForDate(cal), getWeekForDate(cal), null);
+    }
+
+    private Calendar createDateFromWeek(int year, int week) {
+        Calendar date = Calendar.getInstance();
+        date.clear();
+        date.setFirstDayOfWeek(Calendar.MONDAY);
+        date.setMinimalDaysInFirstWeek(4);
+        date.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
+        date.set(Calendar.YEAR, year);
+        date.set(Calendar.WEEK_OF_YEAR, week);
+        return date;
+    }
+
+    @Override
+    protected Calendar createDateFromValue(long value) {
+        Calendar date = Calendar.getInstance();
+        date.clear();
+        date.setFirstDayOfWeek(Calendar.MONDAY);
+        date.setMinimalDaysInFirstWeek(4);
+        date.setTimeInMillis(value);
+        return date;
+    }
+
+    public static int getISOWeekYearForDate(Calendar date) {
+        int year = date.get(Calendar.YEAR);
+        int month = date.get(Calendar.MONTH);
+        int week = date.get(Calendar.WEEK_OF_YEAR);
+        if (month == 0 && week > 51) {
+            year--;
+        } else if (month == 11 && week == 1) {
+            year++;
+        }
+        return year;
+    }
+
+    public static int getWeekForDate(Calendar date) {
+        return date.get(Calendar.WEEK_OF_YEAR);
+    }
+
+    @Override
+    protected void setCurrentDate(int year, int week) {
+        Calendar date = createDateFromWeek(year, week);
+        if (date.before(getMinDate())) {
+            setCurrentDate(getMinDate());
+        } else if (date.after(getMaxDate())) {
+            setCurrentDate(getMaxDate());
+        } else {
+            setCurrentDate(date);
+        }
+    }
+
+    private int getNumberOfWeeks() {
+        // Create a date in the middle of the year, where the week year matches the year.
+        Calendar date = createDateFromWeek(getYear(), 20);
+        return date.getActualMaximum(Calendar.WEEK_OF_YEAR);
+    }
+
+    /**
+     * @return The selected year.
+     */
+    @Override
+    public int getYear() {
+        return getISOWeekYearForDate(getCurrentDate());
+    }
+
+    /**
+     * @return The selected week.
+     */
+    public int getWeek() {
+        return getWeekForDate(getCurrentDate());
+    }
+
+    @Override
+    public int getPositionInYear() {
+        return getWeek();
+    }
+
+    @Override
+    protected int getMaxYear() {
+        return getISOWeekYearForDate(getMaxDate());
+    }
+
+    @Override
+    protected int getMinYear() {
+        return getISOWeekYearForDate(getMinDate());
+    }
+
+    @Override
+    protected int getMaxPositionInYear() {
+        if (getCurrentDate().equals(getMaxDate())) {
+            return getWeekForDate(getMaxDate());
+        }
+        return getNumberOfWeeks();
+    }
+
+    @Override
+    protected int getMinPositionInYear() {
+        if (getCurrentDate().equals(getMinDate())) {
+            return getWeekForDate(getMinDate());
+        }
+        return 1;
+    }
+}