Introduction to Symbian Widgets

A widget in a PC system is a desktop gadget. For more information, see Http://baike.baidu.com/view/704016.htmGoogle Desktop gadgets belong to this category. web widgets are also supported since Symbian 9.3 (s60 3.2, uiq 3.3). The running of widgets requires the support of web runtime.

Overview of web widgets

1. The rise of mobile Internet
The business environment of mobile communication is facing rapid changes. An important manifestation is that people rely more and more on the Internet in their work and life, such as a large number of emerging Web 2.0 websites and online communities. At the same time, people's needs for the Internet are becoming more and more diversified. How to combine mobile communication with the Internet is a new and interesting challenge for mobile terminal manufacturers and Internet service providers.

Accessing the Internet on a mobile device is not as convenient as accessing the Internet on a PC, and the web capabilities supported are limited. There are currently two major solutions to this problem, that is, solutions that are subject to Web and PC services. The browser technology of s60 belongs to the latter and is dedicated to providing PC-like browsing experience on mobile devices. Accessing the Internet through a PC is not as convenient and fast as accessing the Internet through a mobile device. In addition, statistics reveal the "" Phenomenon of Website access. Only a few websites are frequently accessed. To address the above issues, the s60 SDK 3rd edition Feature Pack 2 has released a corresponding solution-web widgets (hereinafter referred to as widgets ).

With the promotion of widgets, people will be able to access the Internet anytime and anywhere in the near future, just as people can make calls today.

2. What is a Web widget?
Web widgets are lightweight Web applications that provide users with one-click Services. It is usually designed to have specific functions, such as providing information about weather, stock, auction, etc. Like web pages, it is developed using standard web technologies such as XHTML, CSS, and JavaScript. In this regard, Widgets are web pages that run out of the browser UI.

Compared with other s60 applications, widgets can be downloaded and installed on mobile phones in the same way. This makes it very easy to share.

Widget running is based on WEB run-time (WRT ). WRT is a newly added browser component in s60 SDK 3rd edition Feature Pack 2. It is a Web application development environment.

Visit the following link for more information about widgets,Http://www.forum.nokia.com/main/resources/technologies/browsing/widgets.html.

3. Experience Widgets
Widgets are used in the same way as s60 local applications. As a widget running platform, WRT is designed to seamlessly integrate widgets with the s60 platform to provide users with consistent user experience. For example, each widget can display icons in the Application menu; it can be set to a shortcut key and a left or right soft key in the STANDBY state; it can appear in the active Application List; similar to the existing s60 application management method, such as installation and uninstallation. The following link shows a video of widget installation and usage.Http://www.forum.nokia.com/info/sw.nokia.com/id/4e20baf8-4c58-4d36-be9f-798a168a844d/Web_widget_webinar_zh_Ch.swf.html

4. Install Widgets
As mentioned above, Widgets are managed in the same way as s60 local applications. If you know how to install the s60 local application, you can install the widget smoothly. (Via LinkHttp://discussion.forum.nokia.com/forum/showthread.php? T = 115609 & page = 2, You can download some widget examples ).

The widget is published as an installation package. An installation package is a zip file with the extension. wgz, which contains all the source files of the widget and the root directory of the widget project.

Deploying widgets on your mobile phone is the first step for installation. Widgets can be deployed on mobile phones in three ways:

· Send messages via Bluetooth or infrared to the Information inbox of the target device.

· Transfer to the memory of the target device through an mmccard or USB port.

· Download from s60 web browser.

Correspondingly, the installation process varies depending on the deployment method of widgets:

· Use the File Manager on your mobile phone to open the widget installation package from the mmccard or from the local drive C, and install the widget as prompted (assuming that the widget installation package has been copied to the mmccard or uploaded to the drive C through the USB cable ).

· Open the widget installation package in the Information inbox through the information application and install it as prompted.

· If the MIME type of the widget installation package is set to X-Nokia-widget on the server side, the installation package downloaded to the mobile phone via the s60 browser will be recognized and automatically installed by the browser.

The installed widget appears in the Application menu.

The steps for installing widgets in emulator of s60 3rd edition fp2 are similar to those described above. The common method is to copy the widget installation package to Symbian/9.3/s60_3rd_fp2_beta/epoc32/winscw/C/data/others (take s60 SDK 3rd edition fp2 as an example ), use the File Manager in emulator to open and install the tool.

The link in the previous "experience widgets" section contains a video showing the installation process of widgets.

5. widget Development Process
Development widgets use standard web development technologies, such as XHTML, CSS, and JavaScript. This makes widget development easier to use and has a short development cycle, which generally takes days to weeks.

The widget contains two necessary files: the HTML file and the info. plist file. And other optional files: CSS files, JavaScript files, resource files (tags, backgrounds, etc ). The HTML file defines the widget structure and content. The CSS file defines the layout format of the widget, such as font and color. Javascript adds dynamic effects to widgets to make them intelligent.

The widget Project is a directory in the file system. This directory contains all the widgets. The required and Image File (icon.png) of widgetmust be in the root directory of the widget project.

The widget development process is as follows:

1. Use the word editor or web ide to compile the widget code

2. When debugging widgets, Firefox and firebug can be combined.

3. Three environments can be used to test widgets:

1) emulator in s60 3rd edition fp2.

2) some mobile phones that support WRT. When writing this article, the available mobile phones include Nokia N95, N95 8g, and n82 with the latest software.

3) remote device access (RDA) test. The information about RDA is located inHttp://apu.ndhub.net.

4. compress the widget file and directory into a zip package, change the extension to. wgz, and install the package on your mobile phone. If necessary, you can repeat steps 1 to 4.

For more information, see the following link:Http://www.forum.nokia.com/info/sw.nokia.com/id/7df9d735-3fe8-4719-aeef-219a85d13552/Getting_Started_with_Nokia_Web_Widget_Development.html. This document provides an example to illustrate how to develop widgets. For more information about WRT APIs, see the following link:Http://www.forum.nokia.com/info/sw.nokia.com/id/cf225acf-7efe-4dae-b89f-967578c00f1d/Web_Run_Time_API_Reference.html.

6. widget Development
WRT is required to run widgets. Currently, Widgets are only information-type widgets that obtain information from the network and present it to users. In addition, WRT supports seamless integration of widgets and s60 in many aspects, mainly reflected in the management and usage of widgets, and can provide users with a consistent user experience.

In the next phase, Widgets will be further integrated into the smartphone platform. For example, widgets can access location, Pim, media, and other mobile device information, as well as services provided by other platforms. The user interface is improved to further improve the user experience.

WRT is a developing platform, and widgets will also have more powerful capabilities and rich functions. If the platform security problem is solved, the widget can access the services provided by the s60 platform through the s60 API. At that time, the development and deployment of Widgets may require a verification process similar to the Symbian signature.