# GNOME Weather Applet

Copyright © 1999-2000 by Spiros Papadimitriou and Dan Mueth

# GNOME Weather Applet

`GNOME Weather` applet, shown in Figure 1, retrieves and displays various weather information. To add this applet to a Panel, right-click on the Panel and choose Panel->Add to panel->Applet->Utility->GNOME Weather.

Figure 1. GNOME Weather Applet

## Usage

`GNOME Weather` displays the current temperature and weather conditions in numeric and iconified form inside the applet. For further information, double-click on the applet. This will open up the Weather Information Window, shown in Figure 2. This displays the current weather information and either a one-day or five-day forecast.

Figure 2. Weather Information Window

Right-clicking on the applet brings up a menu containing the following items:

- Update — refreshes the weather information and display.

- Properties… — opens the `Properties` dialog.

- Help — displays this document.

- About… — shows basic information about `GNOME Weather Applet`, inluding the applet's version and the author's name.

## Customization

You can customize `GNOME Weather` applet by right-clicking on it and choosing Properties…. This will open the Properties dialog(shown in Figure 3), which allows you to change various settings.

Figure 3. Properties dialog

The properties in the `Basic` tab are:

- Update Interval — This option determines how often `GNOME Weather` will connect to the server(s) and retrieve weather information. Current conditions, forecast and radar map (if enabled) will be downloaded

  | Note About Server Updates
  | Note that the `Update Interval` only determines how often your computer downloads information from the server(s). The update time shown in the Current Conditions tab (viewed by double-clicking on the applet) indicates when those measurements were renewed on the server, rather than when they were last retrieved.

  | Disabling Automatic Updates and Using Manual Updates
  | You can disable automatic updates by unchecking the `Update enabled` box. On the other hand, you can also force `GNOME Weather` to perform an update by choosing the corresponding option in the popup menu. These two options are very useful if you have an intermitant internet connection, such as a laptop or modem provides.

- Update enabled — Select this if you would like `GNOME Weather` to automatically download the latest weather information at the time interval specified by `Update`. Deselect this if you would only like weather updates to be done manually, by right-clicking on the applet and selecting Update.

- Use metric — By default `GNOME Weather` uses the imperial system of units. Select this box to use metric units. The units used are shown in Table 1.

  Table 1. Measurement Units

  Quantity | Metric | Imperial
  --- | --- | ---
  Temperature | deg Celsius | deg Farenheit
  Windspeed | km/h | mph
  Pressure | mmHg | inHg
  Visibility | km | miles

- Detailed Forecast — Select this if you would like `GNOME Weather` to retrieve the full five day forecast for your particular area. Note that these forecasts may not be available for some locations.

  The forecast retrieved when this button is not selected is a brief forecast for the broader area containing the selected location (usually the entire state) and typically is a 5-day forecast.

  | Forecast Availability
  | Note that the detailed forecasts downloaded from IWIN are available only for US cities.

The properties in the `Network` tab should be used if your computer is located behind a firewall. These properties are:

- Use proxy — Select this button if your computer is behind a firewall and you must use an HTTP proxy to access the Web.

- Proxy host — Enter your proxy host IP address here (if you are using a HTTP proxy).

- Username — Enter your username here.

- Password — Enter your password here. (Note that this password will be saved in a private configuration file but will not be encrypted.)

The `Location` tab allows you to specify the geographic location that you would like `GNOME Weather` applet to display the weather information for. Click on any plus (+) symbol to expand the tree or any minus (-) symbol to collapse a tree branch. Select the city or region by clicking with the first mouse button.

Locations are organized in a three-level hierarchy. The top level contains broader geographical areas, the second contains sub-regions of these areas and the last contains the particular locations. This hierarchy is essentially based on the way information is organized in the US NWS (National Weather Service), and that is the reason that the US and Canada appear on the topmost level.

After you have made all the changes you want, click on OK to apply the changes and close the Properties dialog. To cancel the changes and return to previous values, click the Cancel button.

## Further Information

`GNOME Weather` has a homepage at http://gweather.dhs.org/. Here you can find the latest Locations file, which is periodically updated with new cities, as sent in by users. If your city is not included in the distribution, please send an email to Spiros Papadimitriou (`<spapadim+@cs.cmu.edu>`) with the necessary information and it will be included in the next release.

You may also want to visit the homepage if you are curious to see what's new.

## Known Bugs and Limitations

### Blocking Input/Output

Even though `GNOME Weather` now uses non-blocking I/O to retrieve data from the network, there are still some steps that block execution. Most notably, establishing a TCP connection to remote hosts is a blocking operation. Because the NWS and IWIN web servers are often heavily loaded, this step may take a significant amount of time. While that happens, the application is unable to respond to CORBA requests from the Panel. In its current implementation, the Panel iterates through all applications and sends frequent CORBA requests (eg. for saving state). If an applet cannot respond for any reason, then the Panel will block waiting for a response.

While the Panel is blocked, it will not respond to any user (or application) requests. For instance, Panel movement and Panel menus (the ones that appear upon a right click) will not work. However, other applets in the Panel should work (unless they have made a CORBA request to the Panel, eg. for querying Panel size). As soon as the blocking operation in `GNOME Weather` completes, things should return to normal (and user interface requests that were buffered will be executed).

There is an experimental version of `GNOME Weather` that uses a separate thread for HTTP processing, which may be incorporated (temporarily) in the next release. However, the final solution is `gnome-vfs` which will be part of GNOME 2.0 and will offer cross-platform support for fully asynchronous I/O.

## Frequently Asked Questions

This is a list of frequently asked questions about `GNOME Weather`. For further information and updates, please visit the GNOME Weather homepage. If your question is still unresolved, you can email the author at `<spapadim+gweather@cs.cmu.edu>`.

### Why does GNOME Weather freezes my Panel?

This is due to the blocking nature of certain network operations (see also the section called Blocking Input/Output) and due to the way the Panel currently works.

### Why does location list appears empty?

This is probably because the `Locations` file was not installed in the proper place. This is usually because `GNOME Weather` and GNOME were not configured in the same way. The file containing the locations must be installed in the `gweather` subdirectory, under the gnome data directory. You can find out the latter with the `gnome-config --datadir` command.

If you have compiled gnome-applets yourself, make sure that you have used `configure --prefix=`gnome-config --prefix` --sysconfdir=`gnome-config --sysconfdir``. Binary RPMs assume a that the prefix and sysconfdir are `/usr` and `/etc`, respectively. If you have compiled GNOME yourself with different options, you need to download and compile gnome-applets yourself.

### Why does GNOME Weather display a question mark and dashes for current conditions?

This will happen if `GNOME Weather` cannot access the NWS server for any reason. This may be because your network connection is down, or the NWS server is down, or maybe the NWS server does not currently have any information about your location.

### Why does GNOME Weather say that a forecast is not available?

If you have enabled detailed forecasts, then it is possible that one may not be available for your location. In this case, try disabling detailed forecasts.

Another possible reason is that the IWIN server is down and `GNOME Weather` cannot retrieve forecast information. The problem should go away as soon as the IWIN server is up again.

## Authors

`GNOME Weather` was written by Spiros Papadimitriou (`<spapadim+@cs.cmu.edu>`). Please send all comments, suggestions, and bug reports to the GNOME bug tracking database. (Instructions for submitting bug reports can be found on-line. If you are using GNOME 1.1 or later, you can also use `Bug Report Tool` (bug-buddy), available in the Utilities submenu of Main Menu, for submitting bug reports.

This manual was written by Spiros Papadimitriou (`<spapadim+@cs.cmu.edu>`) and Dan Mueth (`<d-mueth@uchicago.edu>`). Please send all comments and suggestions regarding this manual to the GNOME Documentation Project by sending an email to `<docs@gnome.org>`. You can also submit comments online by using the GNOME Documentation Status Table.

## License

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

A copy of the GNU General Public License is included as an appendix to the GNOME Users Guide. You may also obtain a copy of the GNU General Public License from the Free Software Foundation by visiting their Web site or by writing to

Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307
USA