# Using the Panels

This chapter describes how to use the panels at the top and bottom of the GNOME Desktop, how to customize the objects that appear on them, and how to add new panels to the desktop.

## 简介

A panel is an area in the GNOME Desktop where you have access to certain actions and information, no matter what the state of your application windows. For example, in the default GNOME panels, you can launch applications, see the date and time, control the system sound volume, and more.

You can customize panels to your liking. You can change their behavior and appearance, and you can add or remove objects from your panels. You can create multiple panels, and choose different properties, objects, and backgrounds for each panel. You can also hide panels.

By default, the GNOME Desktop contains a panel at the top edge of the screen, and a panel at the bottom edge of the screen. The following sections describe these panels.

### Top Edge Panel

By default, the top edge panel contains the following objects:

Your distribution of GNOME may have altered this default setup.

Menu Bar applet

  The panel menubar contains the Applications, the Places, and the System menu. For more on the menu bar, see .

Web Browser Launcher

  Click on this launcher to open the web browser.

Notification Area applet

  Displays icons from other applications that may require your attention, or that you may want to access without switching from your current application window. For more on this, see .

  Until an application adds an icon to the notification area, only a narrow bar is visible.

Clock applet

  Clock shows the current time. Click on the time to open a small calendar. For more on this, see the Clock Applet Manual.

Volume Control applet

  Volume Control enables you to control the volume of the speaker on your system. For more on this, see the Volume Control Manual.

Window Selector icon

  Window Selector lists all your open windows. To give focus to a window, click on the window selector icon at the extreme right of the top edge panel, then select the window. For more on this, see .

### Bottom Edge Panel

By default, the bottom edge panel contains the following objects:

Your distribution of GNOME may have altered this default setup.

Show Desktop button

  Click on this button to minimize all open windows and show the desktop.

Window List applet

  Displays a button for each window that is open. Window List enables you to minimize and restore windows. For more on this, see .

Workspace Switcher applet

  Enables you to switch between your workspaces. For more on workspaces, see .

## Managing Panels

The following sections describe how to manage your panels.

To interact with a panel, you must click on the vacant space on the panel, rather than any of the objects it holds. You can also middle-click or right-click on one of the hide buttons to select the panel, if the panel has no vacant space. If the hide buttons are not visible on a panel, modify the properties of the panel so that the hide buttons are visible.

### Moving a Panel

Drag a panel to another side of the screen to move it there. Click on any vacant space on the panel to begin the drag.

A panel that is not set to expand to the full width of the screen can be dragged away from the edge of the screen and placed anywhere. See for details on how to set a panel's expand property.

### Panel Properties

You can change the properties of each panel, such as the position of the panel, the hide behavior, and the visual appearance.

To modify the properties of a panel, right-click on a vacant space on the panel, then choose Properties. The Panel Properties dialog contains two tabbed sections, General and Background.

#### General Properties Tab

In the General tab, you can modify panel size, position, and hiding properties. The following table describes the dialog elements on the General tabbed section:

Dialog Element | Description
--- | ---
Orientation | Select the position of the panel on your screen. Click on the required position for the panel.
Size | Use the spin box to specify the size of the panel.
Expand | By default, a panel expands to the full length of the edge of the screen where it is located. A panel that does not expand can be moved away from the screen edges to any part of the screen.
Autohide | Select this option if you want the panel to only be fully visible when the mouse pointer is over it. The panel hides off-screen along its principal edge, leaving a narrow part along the edge of the desktop. Move the mouse pointer over the visible part of the panel to make it move fully into the screen.
Show hide buttons | Select this option to display hide buttons at each end of your panel. Clicking on a hide button moves the panel lenthways, hiding it off-screen except for the hide button at the opposite end. Click this hide button to restore the panel to being fully visible.
Arrows on hide button | Select this option to display arrows on the hide buttons, if the hide button is enabled.

#### Background Properties Tab

You can choose the type of background for the panel in the Background tab. The choices are as follows:

Dialog Element | Description
--- | ---
None (use system theme) | Select this option to have the panel use the settings in the Theme preference tool. This keeps your panel's background looking the same as the rest of the desktop and applications.
Solid color | Select this option to specify a single color for the panel background. Click on the Color button to display the color selector dialog. Choose the color that you require from the color selector dialog. Use the Style slider to specify the degree of transparency or opaqueness for the color. For example, to make the panel transparent, move the slider to the Transparent end.
Background image | Select this option to specify an image for the panel background. Click on the button to browse for the file. When you have selected the file, click OK.

You can also drag a color or image on to a panel to set the color or image as the background of the panel. You can drag a color or image from many applications. For example:

- You can drag a color from any color selector dialog.

- You can drag an image file from the Nautilus file manager to set it as the background of the panel.

- You can drag a color or a pattern from the Backgrounds and Emblems dialog in Nautilus file manager to a panel to set it as the background.

Click Close to close the Panel Properties dialog.

### Hiding a Panel

You can hide or show panels. To hide a panel, use a hide button. If the hide buttons are not visible on a panel, modify the panel properties so that the hide buttons are visible.

Hide buttons are at either end of a panel. The hide buttons contain an optional arrow icon. The following illustration shows hide buttons.

A horizontal panel and a vertical panel, both with hide buttons.

To hide a panel, click on one of the hide buttons. The panel reduces in the direction of the arrow on the hide button. The hide button at the other end of the panel remains visible.

To show a hidden panel again, click on the visible hide button. The panel expands in the direction of the arrow on the hide button. Both hide buttons are now visible.

You can set a panel to autohide. When you set autohide, the panel hides automatically when the mouse is not pointing to the panel. The panel reappears when you point to the part of the screen where the panel resides. To set your panel to autohide, modify the properties of the panel.

### Adding a New Panel

To add a panel, right-click on a vacant space on any panel, then choose New Panel. The new panel is added to the GNOME Desktop. The new panel contains no objects. You can customize the new panel to suit your preferences.

### Deleting a Panel

To delete a panel from the GNOME Desktop, right-click on the panel that you want to delete, then choose Delete This Panel.

You must always have at least one panel in the GNOME Desktop. If you have only one panel in the GNOME Desktop, you cannot delete that panel.

## Panel Objects

This section describes the objects that you can add to your panels, and use from your panels.

### Interacting With Panel Objects

You use the mouse buttons to interact with a panel object in the following ways:

Left-click

  Launches the panel object.

Middle-click

  Enables you to grab an object, then drag the object to a new location.

Right-click

  Opens the panel object popup menu.

#### To Select an Applet

Some restrictions apply on where you can click on an applet in order to display the panel object popup menu, or to move the applet, as follows:

- Some applets have popup menus of applet-specific commands that open when you right-click on particular parts of the applet. For example, the Window List applet has a vertical handle on the left side, and buttons that represent your windows on the right side. To open the panel object popup menu for the Window List applet, you must right-click on the handle. If you right-click on a button on the right side, a popup menu for the button opens.

- Some applets have areas that you cannot use to select the applet. For example, the Command Line applet has a field in which you enter commands. You cannot middle-click or right-click on this field to select the applet. Instead, middle-click or right-click on another part of the applet.

### Adding an Object to a Panel

To add an object to a panel, perform the following steps:

1. Right-click on a vacant space on a panel to open the panel popup menu.

2. Choose Add to Panel.

   The Add to Panel dialog opens.The available panel objects are listed alphabetically, with launchers at the top.

   You can type a part of the name or description of an object in the find box. This will narrow the list to those objects that match what you type.

   To restore the full list, delete the text in the find box.

3. Either drag an object from the list to a panel, or select an object from the list and click Add to add it at the spot on the panel where you first right-clicked.

You can add also add any item in the Applications menu to the panel: right-click the menu item and choose Add this launcher to panel.

Each launcher corresponds to a `.desktop` file. You can drag the `.desktop` file on to your panels to add the launcher to the panel.

### Modifying the Properties of an Object

Some panel objects, such as launchers and drawers, have a set of associated properties. The properties are different for each type of object. The properties specify details such as the following:

- The command that starts a launcher application.

- The location of the source files for a menu.

- The icon that represents the object.

To modify the properties of an object perform the following steps:

1. Right-click on the object to open the panel object popup menu, as shown in .

   #### Panel Object Popup Menu

   Panel object popup menu. Menu items: Properties, Remove From Panel, Lock, Move.

2. Choose Properties. Use the Properties dialog to modify the properties as required. The properties in the Properties dialog depend on which object you select in step 1.

3. Click OK to apply the changes, then close the Properties dialog.

### Moving a Panel Object

You can move panel objects within a panel, and from one panel to another panel. You can also move objects between panels and drawers.

To move a panel object, middle-click and hold on the object and drag the object to a new location. When you release the middle mouse button, the object anchors at the new location.

Alternatively, you can use the panel object popup menu to move an object, as follows:

1. Right-click on the object, then choose Move.

2. Point to the new location for the object, then click any mouse button to anchor the object to the new location. This location can be on any panel that is currently in the GNOME Desktop.

Movement of a panel object affects the position of other objects on the panel. To control how objects move on a panel, you can specify a movement mode. To specify the movement mode, press one of the following keys as you move the panel object:

Key | Movement Mode | Description
--- | --- | ---
No key | Switched movement | The object swaps places with other panel objects. Switched movement is the default movement mode.
Alt key | Free movement | The object jumps over other panel objects into the next vacant space on the panel.
Shift key | Push movement | The object pushes other panel objects further along the panel.

### Locking a Panel Object

You can lock panel objects so that the objects stay in the same position on the panel. Use this if you do not want some panel objects to change position when you move other panel objects.

To lock an object to the current location of the object in the panel, right-click on the object to open the panel object popup menu, then select Lock on Panel. Deselect this to unlock the object.

### Removing a Panel Object

To remove an object from a panel right-click on the object to open the panel object popup menu, then choose Remove From Panel.

## Applets

An applet is a small application whose user interface resides within a panel. You use the applet panel object to interact with the applet. For example, the following figure shows the following applets, from left to right:

- Window List: Displays the windows currently open on your system.

- CD Player: Enables you to control the compact disc player on your system.

- Volume Control: Enables you to control the volume of the speaker on your system.

Sample applets. The context describes the graphic.

## Launchers

A launcher is an object that performs a specific action when you open it.

You can find launchers in the panels, in the panel menubar, and on the desktop. A launcher is represented by an icon in all of these locations.

You might use a launcher to do any of the following:

- Start a particular application.

- Execute a command.

- Open a folder.

- Open a Web browser at a particular page on the Web.

- Open special Uniform Resource Identifiers (URIs). The GNOME Desktop contains special URIs that enable you to access particular functions from the file manager.

You can modify the properties of a launcher. For example, the properties of a launcher include the name of the launcher, the icon that represents the launcher, and how the launcher runs. For more on this, see .

In certain situations, a launcher in a menu might not show an icon. For example, if it specifies no icon to display, or if the entire menu is set to show no icons.

### Adding a Launcher to a Panel

You can add a launcher to a panel in one of the following ways:

- From the panel popup menu

  Right-click on any vacant space on the panel, then choose Add to Panel. The Add to Panel dialog opens.

  To create a new launcher, select Custom Application Launcher from the list. A Create Launcher dialog is displayed. For more information on the properties in this dialog, see .

  Alternatively, to add an existing launcher to the panel, select Application Launcher from the list. Choose the launcher that you want to add from the list of menu items.

- From any menu

  To add a launcher to a panel from any menu, perform one of the following steps:

  - Open a menu that contains the launcher. Drag the launcher on to the panel.

  - Open the menu that contains the launcher from the panel where you want the launcher to reside. Right-click on the title of the launcher. Choose Add this launcher to panel.

- From the file manager

  To add a launcher to a panel from the file manager, find the `.desktop` file for the launcher in your file system, then drag the `.desktop` file to the panel.

### Modifying a Launcher

To modify the properties of a launcher in a panel, perform the following steps:

1. Right-click on the launcher to open the panel object popup menu.

2. Choose Properties. Use the Launcher Properties dialog to modify the properties as required. For more information on the Launcher Properties dialog, see .

3. Click Close to close the Launcher Properties dialog.

### Launcher Properties

When you create or edit a launcher, the following properties can be set:

Type

  Use the drop-down list to specify whether this launcher starts an application or opens a document:

  Application

    The launcher starts an application.

  Application in Terminal

    The launcher starts an application in a terminal.

  文件

    The launcher opens a file.

Name

  This is displayed when you add the launcher to a menu or to the desktop.

Command

  For an application launcher, specify a command to execute when you click on the launcher. For sample commands, see .

Location

  For a file launcher, specify the location of the file.

Comment

  This is displayed as a tooltip when you point to the launcher icon on the panel.

To choose an icon for the launcher, click on the No Icon button. An icon selector dialog is displayed. Choose an icon from the dialog.

To change the icon for the launcher, click on the button showing the current icon. An icon selector dialog is displayed. Choose an icon from the dialog.

#### Launcher Commands

The type of commands that you can enter in the Command field depend on the option that you choose from the Type drop-down combination box. If you choose Application from the Type drop-down combination box, you can enter a normal command. The following table shows some sample commands and the actions that the commands perform:

Sample Application Command | Action
--- | ---
`gedit` | Starts the gedit text editor application.
`gedit /user123/loremipsum.txt` | Opens the file `/user123/loremipsum.txt` in the gedit text editor application.
`nautilus /user123/Projects` | Opens the folder `/user123/Projects` in a file object window.

If you choose Link from the Type drop-down combination box, you can enter a link command. The following table shows some sample link commands and the actions that the commands perform:

Sample Link Command | Action
--- | ---
`http://www.gnome.org` | Opens the GNOME website in your default browser.
`ftp://ftp.gnome.org` | Opens the GNOME FTP site in your default browser.

The command can contain the following special codes which will be replaced with the value specified in the following table:

Code | Meaning
--- | ---

`%f`

A single file name, even if multiple files are selected. The system reading the desktop entry should recognize that the program in question cannot handle multiple file arguments, and it should should probably spawn and execute multiple copies of a program for each selected file if the program is not able to handle additional file arguments. If files are not on the local file system (i.e. are on HTTP or FTP locations), the files will be copied to the local file system and %f will be expanded to point at the temporary file. Used for programs that do not understand the URL syntax.

`%F` | A list of files. Use for apps that can open several local files at once.
`%u` | A single URL.
`%U` | A list of URLs.
`%d` | Directory containing the file that would be passed in a %f field.
`%D` | List of directories containing the files that would be passed in to a %F field.
`%n` | A single filename (without path).
`%N` | A list of filenames (without paths).
`%i` | The Icon field of the desktop entry expanded as two parameters, first --icon and then the contents of the Icon field. Should not expand as any parameters if the Icon field is empty or missing.
`%c` | The translated Name field associated with the desktop entry.
`%k` | The location of the desktop file as either a URI (if for example gotten from the vfolder system) or a local filename or empty if no location is known.
`%v` | The name of the Device entry in the desktop file.

These are as defined by freedesktop.org's Desktop Entry Specification.

## Buttons

You can add buttons to your panels to provide quick access to common actions and functions.

### Force Quit Button

Force Quit icon.

The Force Quit button enables you to select a window to terminate an application. This button is useful if you want to terminate an application that does not respond to your commands.

To terminate an application, click on the Force Quit button, then click on a window from the application that you want to terminate. If you do not want to terminate an application after you click on the Force Quit button, press Esc.

### Lock Screen Button

Lock screen icon.

The Lock Screen button locks your screen and activates your screensaver. To access your session again, you must enter your password.

To add a Lock Screen button to a panel, right-click on any vacant space on the panel. Choose Add to Panel, then choose Lock Screen from the Add to Panel dialog. See for more on this.

Right-click on the Lock Screen button to open a menu of screensaver-related commands. describes the commands that are available from the menu.

#### Lock Screen Menu Items

Menu Item | 功能
--- | ---
Activate Screensaver | Activates the screensaver immediately. This will also lock the screen if you have set Lock screen when screensaver is active in the Screensaver preference tool.
Lock Screen | Locks the screen immediately. This command performs the same function as when you click on the Lock Screen button.
Properties | Opens the Screensaver preference tool, with which you can configure the type of screensaver that is displayed when you lock the screen.

### Log Out Button

Log Out icon.

The Log Out button begins the process to log out of a GNOME session.

To add a Log Out button to a panel, right-click on any vacant space on the panel. Choose Add to Panel Actions Log Out. To log out of your session or shut down your system, click on the Log Out button.

### Run Button

Run Application icon.

You can use the Run button to open the Run Application dialog.

To add a Run button to a panel, right-click on any vacant space on the panel. Choose Add to Panel Actions Run. To open the Run Application dialog, click on the Run button.

For more information on the Run Application dialog, see Working With Menus.

### Screenshot Button

Screenshot icon.

You can use the Screenshot button to take a screenshot of your screen.

To add a Screenshot button to a panel, right-click on any vacant space on the panel. Choose Add to Panel Actions Screenshot. To take a screenshot of your screen, click on the Screenshot button.

For more information on how to take screenshots, see Working With Menus.

### Search Button

Search Tool icon.

You can use the Search button to open the Search Tool.

To add a Search button to a panel, right-click on any vacant space on the panel. Choose Add to Panel Actions Search. To open the Search Tool, click on the Search button.

For more information on the Search Tool, see the Search Tool Manual.

### Show Desktop Button

Show Desktop icon.

You can use the Show Desktop button to minimize all open windows and show the desktop.

To add a Show Desktop button to a panel, right-click on any vacant space on the panel. Choose Add to Panel Actions Show Desktop. To minimize all windows and show the desktop, click on the Show Desktop button.

## Menus

You can add the following types of menu to your panels:

- Main Menu: You can access almost all of the standard applications, commands, and configuration options from the Main Menu. To add a Main Menu to a panel, right-click on any vacant space on the panel, then choose Add to Panel Main Menu. You can add as many Main Menu objects to your panels as you want.

- Menu Bar: You can access almost all of the standard applications, commands, and configuration options from the menus in the Menu Bar. The Menu Bar contains the Applications menu and the Actions menu. To add a Menu Bar to a panel, right-click on any vacant space on the panel, then choose Add to Panel Menu Bar. You can add as many Menu Bar objects to your panels as you want.

- System menus: System menus contain the standard applications and tools that you can use in the GNOME Desktop. The Applications menu and Actions menu are system menus. To add a system menu to a panel, right-click on a launcher in the menu, then choose Entire menu Add this as menu to panel.

## Drawers

A drawer is an extension of a panel. You can open and close a drawer in the same way that you can show and hide a panel. A drawer can contain all panel objects, including launchers, menus, applets, other panel objects, and other drawers. When you open a drawer, you can use the objects in the same way that you use objects on a panel.

The following figure shows an open drawer that contains two panel objects.

Open drawer. The context describes the graphic.

The arrow on the drawer icon indicates that the icon represents a drawer or menu.

You can add, move, and remove objects from drawers in the same way that you add, move, and remove objects from panels.

### To Open and Close a Drawer

To open a drawer, click on the drawer object in a panel. You can close a drawer in the following ways:

- Click on the drawer.

- Click on the drawer hide button.

### To Add a Drawer to a Panel

You can add a drawer to a panel in the following ways:

- From the panel popup menu

  Right-click on any vacant space on the panel, then choose Add to Panel Drawer.

- From any menu

  You can add a menu as a drawer object to a panel.

  To add a menu as a drawer to a panel, open the menu from the panel. Right-click on any launcher in the menu, then choose Entire menu Add this as drawer to panel.

### To Add an Object to a Drawer

You add an object to a drawer in the same way that you add objects to panels. For more information, see .

### To Modify Drawer Properties

You can modify properties for each individual drawer. You can change features for each drawer, such as the visual appearance of the drawer and whether the drawer has hide buttons.

To modify properties for a drawer perform the following steps:

1. Right-click on the drawer, then choose Properties to display the Panel Properties dialog. The dialog displays the General tabbed section.

2. Select the properties for the drawer in the dialog. The following table describes the elements on the General tabbed section:

   Dialog Element | Description
   --- | ---
   Name | Type a name for the panel. When you use shortcut keys to switch between your panels and the desktop, this panel name is displayed.
   Size | Select the size of the panel.
   Icon | Choose an icon to represent the drawer. Click on the Icon button to display an icon selector dialog. Choose an icon from the dialog. Alternatively, click Browse to choose an icon from another directory. When you choose an icon, click OK.
   Show hide buttons | Select this option to display hide buttons on your panel.
   Arrows on hide button | Select this option to display arrows on the hide buttons, if the hide button is enabled.

3. You can use the Background tabbed section to set the background for the drawer. For information on how to complete the Background tabbed section, see the step on this topic in . You can also drag a color or image on to a drawer to set the color or image as the background of the drawer. For more information, see .

4. Click Close to close the Panel Properties dialog.

## Default Panel Objects

This section covers the panel objects that appear in the default GNOME desktop.

### Window Selector Applet

You can view a list of all windows that are currently open. You can also choose a window to give focus to. To view the window list, click on the Window Selector applet. The following figure shows an example of the Window Selector applet:

Window selector applet displayed from the top edge panel.

To give focus to a window, select the window from the Window Selector applet.

The Window Selector lists the windows in all workspaces. The windows in all workspaces other than the current workspace, are listed under a separator line.

### Notification Area Applet

Notification Area icon.

The Notification Area applet displays icons from various applications to indicate activity in the application. For example, when you use the CD Player application to play a CD, a CD icon is displayed in the Notification Area applet. The graphic above illustrates the CD icon in the Notification Area applet.

To add a Notification Area applet to a panel, right-click on any vacant space on the panel. Choose Add to Panel Utility Notification Area.

### Main Menu panel object

The Main Menu provides access to the Applications menu and many of the items in the System menu. You can access almost all of the standard applications, commands, and configuration options from the Main Menu.

You can add Main Menu buttons to your panels. Click on the Main Menu button to open the Main Menu.

#### To Add a Main Menu to a Panel

You can add as many Main Menu buttons as you want to your panels. To add a Main Menu to a panel, right-click on any vacant space on the panel. Choose Add to Panel and choose Main Menu from the Add to Panel dialog.

### Menu Bar panel object

Menu Bar applet. Menus: Applications, Places, Desktop.

The Menu Bar provides access to the panel menubar, which contains the Applications, Places, and System menus. You can access almost all of the standard applications, commands, and configuration options from the Menu Bar. For more on using the panel menubar, see .

#### To Add a Menu Bar to a Panel

You can add as many Menu Bar applets as you want to your panels. To add a Menu Bar to a panel, right-click on any vacant space on the panel. Choose Add to Panel and choose Menu Bar from the Add to Panel dialog.

### Window List

The Window List applet enables you to manage the windows that are open on the GNOME desktop. Window List uses a button to represent each window or group of windows that is open. The state of the buttons in the applet varies depending on the state of the window that the button represents. The following table explains the possible states of the Window List buttons.

State | Indicates...
--- | ---
Button is pressed in. | The window has focus.
The button appears faded. | The window is minimized.
Button is not pressed in, and is not faded. | The window is displayed on the desktop and is not minimized.
There is a number in parentheses at the end of the button title. | The button represents a group of buttons.

#### Usage

You can use Window List to perform the following tasks:

- To give focus to a window

  If you click on the Window List button that represents a window that is on the desktop but does not have focus, the applet gives focus to the window.

- To minimize a window

  If you click on the Window List button that represents the window that has focus, the applet minimizes the window.

- To restore a minimized window

  If you click on the Window List button that represents a minimized window, the applet restores the window.

#### Preferences

To configure Window List, right-click on the handle on the left of the buttons, then choose Preferences. The Window List Preferences dialog contains two tabbed sections.

##### Behavior

Window List Content

  To specify which windows to display in Window List, select one of the following options:

  - Show windows from current workspace

    Select this option to only show the windows that are open in the current workspace.

  - Show windows from all workspaces

    Select this option to show the windows that are open in all workspaces.

Window Grouping

  To specify when Window List groups windows that belong to the same process, select one of the following options:

  - Never group windows

    Select this option to never group windows of the same process under one Window List button.

  - Group windows when space is limited

    Select this option to group windows of the same process under one Window List button when the space on the panel is restricted.

  - Always group windows

    Select this option to always group windows of the same process under one Window List button.

Restoring Minimized Windows

  To define how Window List behaves when you restore windows, select one of the following options:

  - Restore to current workspace

    Select this option to restore a window from the applet to the current workspace, even if the window did not previously reside in the current workspace.

  - Restore to native workspace

    Select this option to switch to the native workspace in which a window resides when you restore the window from the applet.

##### Size

Window List Size

  The size of the Window List applet varies depending on the size of the panel in which the applet resides. Use the following spin boxes to set limitations on the size of the applet:

  - Minimum size ... pixels

    Use the spin box to specify the minimum size of the applet. If the panel is smaller than the minimum size specified, the panel adjusts in size to fit the applet.

  - Maximum size ... pixels

    Use the spin box to specify the maximum size of the applet.