/*
* Copyright 2008 Google Inc.
*
* 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.google.gwt.user.datepicker.client;
import com.google.gwt.dom.client.Element;
import com.google.gwt.event.dom.client.ChangeEvent;
import com.google.gwt.event.dom.client.ChangeHandler;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.safehtml.shared.annotations.IsSafeHtml;
import com.google.gwt.user.client.ui.FlexTable;
import com.google.gwt.user.client.ui.ListBox;
import com.google.gwt.user.client.ui.PushButton;
import com.google.gwt.user.client.ui.Widget;
import java.util.Date;
/**
* A simple {@link MonthSelector} used for the default date picker. It allows to select months and
* years but the name is not changed for backward compatibility. Also not extensible as we wish to
* evolve it freely over time.
*/
public final class DefaultMonthSelector extends MonthSelector {
private PushButton monthBackwards;
private PushButton monthForwards;
private FlexTable grid;
private PushButton yearBackwards;
private PushButton yearForwards;
private ListBox monthSelect;
private ListBox yearSelect;
private int monthColumn;
/**
* Returns the button for moving to the previous month.
*/
public Element getBackwardButtonElement() {
return monthBackwards.getElement();
}
/**
* Returns the button for moving to the next month.
*/
public Element getForwardButtonElement() {
return monthForwards.getElement();
}
/**
* Returns the button for moving to the previous year.
*/
public Element getYearBackwardButtonElement() {
return yearBackwards.getElement();
}
/**
* Returns the button for moving to the next year.
*/
public Element getYearForwardButtonElement() {
return yearForwards.getElement();
}
/**
* Returns the ListBox for selecting the month
*/
public ListBox getMonthSelectListBox() {
return monthSelect;
}
/**
* Returns the ListBox for selecting the year
*/
public ListBox getYearSelectListBox() {
return yearSelect;
}
@Override
protected void refresh() {
if (isDatePickerConfigChanged()) {
// if the config has changed since the last refresh, rebuild the grid
setupGrid();
}
setDate(getModel().getCurrentMonth());
}
@Override
protected void setup() {
// previous, next buttons
monthBackwards = createNavigationButton("‹", -1, css().previousButton());
monthForwards = createNavigationButton("›", 1, css().nextButton());
yearBackwards = createNavigationButton("«", -12, css().previousYearButton());
yearForwards = createNavigationButton("»", 12, css().nextYearButton());
// month and year selector
monthSelect = createMonthSelect();
yearSelect = createYearSelect();
// Set up grid.
grid = new FlexTable();
grid.setStyleName(css().monthSelector());
setupGrid();
initWidget(grid);
}
private PushButton createNavigationButton(
@IsSafeHtml String label, final int noOfMonths, String styleName) {
PushButton button = new PushButton();
button.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
addMonths(noOfMonths);
}
});
button.getUpFace().setHTML(label);
button.setStyleName(styleName);
return button;
}
private ListBox createMonthSelect() {
final ListBox monthListBox = new ListBox();
for (int i = 0; i < CalendarModel.MONTHS_IN_YEAR; i++) {
monthListBox.addItem(getModel().formatMonth(i));
}
monthListBox.addChangeHandler(new ChangeHandler() {
@Override
public void onChange(ChangeEvent event) {
int previousMonth = getModel().getCurrentMonth().getMonth();
int newMonth = monthListBox.getSelectedIndex();
int delta = newMonth - previousMonth;
addMonths(delta);
}
});
return monthListBox;
}
private ListBox createYearSelect() {
final ListBox yearListBox = new ListBox();
yearListBox.addChangeHandler(new ChangeHandler() {
@Override
public void onChange(ChangeEvent event) {
int deltaYears = yearListBox.getSelectedIndex() - getNoOfYearsToDisplayBefore();
addMonths(deltaYears * CalendarModel.MONTHS_IN_YEAR);
}
});
return yearListBox;
}
private boolean isDatePickerConfigChanged() {
boolean isMonthCurrentlySelectable = monthSelect.getParent() != null;
boolean isYearNavigationCurrentlyEnabled = yearBackwards.getParent() != null;
return getDatePicker().isYearAndMonthDropdownVisible() != isMonthCurrentlySelectable ||
getDatePicker().isYearArrowsVisible() != isYearNavigationCurrentlyEnabled;
}
private void setDate(Date date) {
if (getDatePicker().isYearAndMonthDropdownVisible()) {
// setup months dropdown
int month = date.getMonth();
monthSelect.setSelectedIndex(month);
// setup years dropdown
yearSelect.clear();
int year = date.getYear();
int startYear = year - getNoOfYearsToDisplayBefore();
int endYear = year + getNoOfYearsToDisplayAfter();
Date newDate = new Date();
for (int i = startYear; i <= endYear; i++) {
newDate.setYear(i);
yearSelect.addItem(getModel().getYearFormatter().format(newDate));
}
yearSelect.setSelectedIndex(year - startYear);
} else {
grid.setText(0, monthColumn, getModel().formatCurrentMonthAndYear());
}
}
private int getNoOfYearsToDisplayBefore() {
return (getDatePicker().getVisibleYearCount() - 1) / 2;
}
private int getNoOfYearsToDisplayAfter() {
return getDatePicker().getVisibleYearCount() / 2;
}
private void setupGrid() {
grid.removeAllRows();
grid.insertRow(0);
// Back arrows
if (getDatePicker().isYearArrowsVisible()) {
addCell(yearBackwards, "1");
}
addCell(monthBackwards, "1");
// Month/Year column
if (getDatePicker().isYearAndMonthDropdownVisible()) {
// Drop-down
if (getModel().isMonthBeforeYear()) {
addCell(monthSelect, "50%", css().month());
addCell(yearSelect, "50%", css().year());
} else {
addCell(yearSelect, "50%", css().year());
addCell(monthSelect, "50%", css().month());
}
} else {
// Text-only
monthColumn = addCell(null, "100%", css().month());
}
// Forward arrows
addCell(monthForwards, "1");
if (getDatePicker().isYearArrowsVisible()) {
addCell(yearForwards, "1");
}
}
private int addCell(Widget widget, String width) {
return addCell(widget, width, null);
}
private int addCell(Widget widget, String width, String className) {
int cell = grid.getCellCount(0);
grid.setWidget(0, cell, widget);
grid.getCellFormatter().setWidth(0, cell, width);
if (className != null) {
grid.getCellFormatter().setStyleName(0, cell, className);
}
return cell;
}
}