/*
* 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.widgetideas.client;
/**
* Currency Text Widget
*
* This class provides a text widget implementation for input currency amount.
* It addresses a few special requirement for currency input, namely, - only
* digits, decimal separator and group separator should be allowed in input. -
* native digits should be handles. - correct currency symbol should be picked
* according to user's locale. - currency symbol should be displayed on the
* right side of the box.
*
* Usage: RootPanel rootPanel = RootPanel.get();
*
* CurrencyWidget currencyWidget = new CurrencyWidget();
* rootPanel.add(currencyWidget, 180, 32);
*
* clickMeButton = new Button(); rootPanel.add(clickMeButton, 394, 32);
* clickMeButton.setText("See what you got!");
* clickMeButton.addClickListener(new ClickListener() { public void
* onClick(Widget sender) { Window.alert("You entered: " +
* Double.toString(currencyWidget.getAmount())); } });
*
*/
import com.google.gwt.core.client.GWT;
import com.google.gwt.i18n.client.NumberFormat;
import com.google.gwt.i18n.client.constants.CurrencyCodeMapConstants;
import com.google.gwt.i18n.client.constants.NumberConstants;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.FocusListener;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.KeyboardListener;
import com.google.gwt.user.client.ui.KeyboardListenerAdapter;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.TextBoxBase;
import com.google.gwt.user.client.ui.Widget;
import com.google.gwt.widgetideas.client.overrides.DOMHelper;
import java.util.Map;
/**
* TODO:Add javadoc
*/
public class CurrencyWidget extends Composite {
protected static final NumberConstants numberConstants = (NumberConstants)
GWT.create(NumberConstants.class);
protected static final CurrencyCodeMapConstants currencyCodeMapConstants =
(CurrencyCodeMapConstants)GWT.create(CurrencyCodeMapConstants.class);
protected static String acceptableCharset = getAcceptedCharset();
private static String getAcceptedCharset() {
StringBuffer strbuf = new StringBuffer();
strbuf.append("0123456789");
if (numberConstants.zeroDigit().charAt(0) != '0') {
for (int i = 0; i < 10; i++) {
strbuf.append(numberConstants.zeroDigit().charAt(0) + i);
}
}
strbuf.append(numberConstants.decimalSeparator().charAt(0));
if (numberConstants.groupingSeparator().charAt(0) == '\u00a0') {
strbuf.append(' ');
} else {
strbuf.append(numberConstants.groupingSeparator().charAt(0));
}
strbuf.append((char) KeyboardListener.KEY_TAB);
strbuf.append((char) KeyboardListener.KEY_BACKSPACE);
strbuf.append((char) KeyboardListener.KEY_DELETE);
strbuf.append((char) KeyboardListener.KEY_ENTER);
strbuf.append((char) KeyboardListener.KEY_HOME);
strbuf.append((char) KeyboardListener.KEY_END);
strbuf.append((char) KeyboardListener.KEY_LEFT);
strbuf.append((char) KeyboardListener.KEY_UP);
strbuf.append((char) KeyboardListener.KEY_RIGHT);
strbuf.append((char) KeyboardListener.KEY_DOWN);
strbuf.append((char) DOMHelper.OTHER_KEY_LEFT);
strbuf.append((char) DOMHelper.OTHER_KEY_UP);
strbuf.append((char) DOMHelper.OTHER_KEY_RIGHT);
strbuf.append((char) DOMHelper.OTHER_KEY_DOWN);
return strbuf.toString();
}
protected final HorizontalPanel horizontalPanel = new HorizontalPanel();
protected final Label currencySymbol;
protected final TextBox amountBox = new TextBox();
protected final NumberFormat formatter = NumberFormat.getFormat(getCurrencyAmountPattern());
protected boolean valueInitiated = false;
/**
* Constructs a CurrencyWidget object.
*/
public CurrencyWidget() {
this(numberConstants.defCurrencyCode());
}
/**
* Constructs a CurrencyWidget object with specified currency.
*
* @param currencyCode International currency code (ISO 4217).
*/
public CurrencyWidget(String currencyCode) {
currencySymbol = new Label(getCurrencySymbol(currencyCode));
initWidget(horizontalPanel);
horizontalPanel.setSpacing(2);
if (isLeadingSymbol()) {
horizontalPanel.add(currencySymbol);
horizontalPanel.add(amountBox);
amountBox.setTextAlignment(TextBoxBase.ALIGN_LEFT);
} else {
horizontalPanel.add(amountBox);
horizontalPanel.add(currencySymbol);
amountBox.setTextAlignment(TextBoxBase.ALIGN_RIGHT);
}
amountBox.setText(formatter.format(0));
amountBox.addFocusListener(new FocusListener() {
public void onFocus(Widget sender) {
if (!valueInitiated) {
amountBox.setText("");
valueInitiated = true;
}
}
public void onLostFocus(Widget sender) {
amountBox.setText(reformatContent());
}
});
amountBox.addKeyboardListener(new KeyboardListenerAdapter() {
public void onKeyDown(Widget sender, char keyCode, int modifiers) {
if (keyCode == (char) KEY_ENTER) {
amountBox.setText(reformatContent());
}
}
public void onKeyPress(Widget sender, char keyCode, int modifiers) {
if (acceptableCharset.indexOf(keyCode) == -1) {
amountBox.cancelKey();
}
if (amountBox.getText().length() >= 16) {
amountBox.cancelKey();
}
}
});
}
/*
* This method is used to retrieve the amount value user inputed. @return user
* inputed value in double.
*/
public double getAmount() {
return formatter.parse(amountBox.getText());
}
protected String getCurrencyAmountPattern() {
return numberConstants.currencyPattern().replace('\u00a4', ' ').trim();
}
protected String getCurrencySymbol(String currencyCode) {
Map currencyMap = currencyCodeMapConstants.currencyMap();
String symbol = (String)currencyMap.get(currencyCode);
if (symbol == null) {
symbol = numberConstants.defCurrencyCode();
}
return symbol;
}
protected boolean isLeadingSymbol() {
return numberConstants.currencyPattern().startsWith("\u00a4");
}
protected String reformatContent() {
String str = amountBox.getText();
if (numberConstants.groupingSeparator().charAt(0) == '\u00a0') {
str = str.replace(' ', '\u00a0');
}
double amount;
try {
amount = formatter.parse(str);
} catch (NumberFormatException e) {
amount = 0.0;
}
return formatter.format(amount);
}
}