/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* C E D A R
* S O L U T I O N S "Software done right."
* S O F T W A R E
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* Copyright (c) 2013-2014 Kenneth J. Pronovici.
* All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the Apache License, Version 2.0.
* See LICENSE for more information about the licensing terms.
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*
* Author : Kenneth J. Pronovici <pronovic@ieee.org>
* Language : Java 6
* Project : Common Java Functionality
*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
package com.cedarsolutions.client.gwt.widget;
import com.cedarsolutions.web.metadata.NativeEventType;
import com.google.gwt.core.client.GWT;
import com.google.gwt.core.client.Scheduler;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.http.client.URL;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.Event.NativePreviewEvent;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.FocusWidget;
import com.google.gwt.user.client.ui.PopupPanel;
/**
* Widget-related utilities, which applications should extend and make a singleton.
* @author Kenneth J. Pronovici <pronovic@ieee.org>
*/
public abstract class AbstractWidgetUtils {
/**
* Get the proper URL for an destination token.
*
* <p>
* This should work even when running with the development mode
* application server. To generate the base URL for the site,
* we take the current URL and chop off everything after the last
* "#" character. This is hack-ish, but there doesn't seem to
* be any other way to do it.
* </p>
*
* @param destinationToken Token to generate URL for
* @return Proper URL for the destination token.
*/
public String getDestinationUrl(String destinationToken) {
String baseUrl = getWndLocationHref().replaceAll("#.*$", "");
return baseUrl + "#" + destinationToken;
}
/**
* Get destination token for a URL.
*
* <p>
* The process here is similar to getDestinationUrl(): we strip
* off everything before the "#" character, and that must be the
* token.
* </p>
*
* @param destinationUrl URL to generate token for
* @return Destination token for the URL
*/
public String getDestinationToken(String destinationUrl) {
return destinationUrl.replaceFirst("^.*#", "");
}
/** Get the token represented by $wnd.location.href. */
public String getWndLocationToken() {
return getDestinationToken(this.getWndLocationHref());
}
/** Get $wnd.location.href from the browser's DOM. */
public String getWndLocationHref() {
return NativeUtils.getWndLocationHref();
}
/** Redirect the current page to an external URL. */
public void redirect(String url) {
NativeUtils.redirect(url);
}
/**
* Open the referenced URL, as for download via a button click.
* @see <a href="http://stackoverflow.com/questions/4703014">Stack Overflow</a>
*/
public void openUrl(String url) {
NativeUtils.openUrl(url);
}
/**
* Get the URL prefix of the hosting page, a proxy over GWT.getHostPageBaseURL().
* @return If non-empty, the base URL is guaranteed to end with a slash
**/
public String getHostPageBaseUrl() {
return GWT.getHostPageBaseURL();
}
/** Encode a URL component, a proxy over GWT's URL.encodeQueryString(). */
public String encodeQueryString(String component) {
return URL.encodeQueryString(component);
}
/** Decode a URL component, a proxy over GWT's URL.decodeQueryString(). */
public String decodeQueryString(String component) {
return URL.decodeQueryString(component);
}
/**
* Use a popup's key preview hooks to close the dialog when enter or escape is pressed.
* @param popup Popup to operate on
* @param preview Preview event passed to popup's onPreviewNativeEvent method
*/
public void closeOnEnterOrEscape(PopupPanel popup, NativePreviewEvent preview) {
if (popup != null && preview != null) {
NativeEvent event = preview.getNativeEvent();
if (event != null) {
if (NativeEventType.KEYDOWN.equals(NativeEventType.convert(event.getType()))) {
switch (event.getKeyCode()) {
case KeyCodes.KEY_ENTER:
case KeyCodes.KEY_ESCAPE:
popup.hide();
break;
}
}
}
}
}
/**
* Use a popup's key preview hooks to click a button when escape is pressed.
* @param preview Preview event passed to popup's onPreviewNativeEvent method
* @param button Button to click.
*/
public void clickButtonOnEscape(NativePreviewEvent preview, Button button) {
if (preview != null) {
NativeEvent event = preview.getNativeEvent();
if (event != null) {
if (NativeEventType.KEYDOWN.equals(NativeEventType.convert(event.getType()))) {
switch (event.getKeyCode()) {
case KeyCodes.KEY_ESCAPE:
button.click();
break;
}
}
}
}
}
/**
* Use a popup's key preview hooks to click a button when enter is pressed.
* @param preview Preview event passed to popup's onPreviewNativeEvent method
* @param button Button to click.
*/
public void clickButtonOnEnter(NativePreviewEvent preview, Button button) {
if (preview != null) {
NativeEvent event = preview.getNativeEvent();
if (event != null) {
if (NativeEventType.KEYDOWN.equals(NativeEventType.convert(event.getType()))) {
switch (event.getKeyCode()) {
case KeyCodes.KEY_ENTER:
button.click();
break;
}
}
}
}
}
/**
* Globally handle the enter key, using it to click the indicated button.
* @param button Button to click when the enter key is pressed
*/
public void clickOnEnter(Button button) {
Event.addNativePreviewHandler(new ClickOnEnterHandler(button));
}
/** Handler that clicks a button when enter is pressed. */
protected static class ClickOnEnterHandler implements Event.NativePreviewHandler {
private Button button;
public ClickOnEnterHandler(Button button) {
this.button = button;
}
@Override
public void onPreviewNativeEvent(NativePreviewEvent event) {
switch (event.getTypeInt()) {
case Event.ONKEYDOWN:
int keyCode = event.getNativeEvent().getKeyCode();
if (keyCode == KeyCodes.KEY_ENTER) {
this.button.click();
}
}
}
}
/**
* Set focus on a widget after the display has been rendered, especially useful for pop-ups.
* @param widget Widget to set focus on
* @see <a href="http://stackoverflow.com/questions/5944612/not-able-to-set-focus-on-textbox-in-a-gwt-app">StackOverflow</a>
*/
public void setFocusAfterDisplay(final FocusWidget widget) {
Scheduler.get().scheduleDeferred(new FocusScheduledCommand(widget));
}
/** Scheduled command that sets focus on a widget. */
protected static class FocusScheduledCommand implements Scheduler.ScheduledCommand {
private FocusWidget widget;
public FocusScheduledCommand(FocusWidget widget) {
this.widget = widget;
}
@Override
public void execute() {
this.widget.setFocus(true);
}
}
}