Look and Feel

In the following sections find examples of how to configure some look and feel aspects of your GNOME desktop, like the desktop background and screens saver, 3D desktop effects, themes, window behavior or menus.

Changing the Desktop Background

The desktop background is the image or color that is applied to your desktop. You can customize the desktop background in the following ways:

  • Select an image for the desktop background. The image is superimposed on the desktop background color. The desktop background color is visible if you select a transparent image or if the image does not cover the entire desktop.

  • Select a color for the desktop background. You can select a solid color or create a gradient effect with two colors. A gradient effect is a visual effect where one color blends gradually into another color.

To change the desktop preferences:

  1. Click Computer+Control Center+Look and Feel+Appearance+Background.

  2. To change the picture on the background select one of the Desktop Background from the list and select the Style in which to arrange the image on the desktop. Your desktop immediately updates to show the new settings

  3. To use a custom picture, click Add and select an image file from the file system.

  4. If you do not want a picture on the background, select No Desktop Background from the Desktop Background list and specify a color scheme using the options in the Color drop-down list and the color selector buttons. Your desktop immediately changes to show the new settings

  5. When you are satisfied with your choices, click Close.

Configuring Fonts

To select the fonts to use in your applications, windows, terminals and desktop, click Computer+Control Center+Look and Feel+Appearance+Fonts.

Figure 3.8. Font Preferences Dialog

Font Preferences Dialog

The upper part of the dialog shows the fonts selected for applications, documents, the desktop, window titles and a fixed-width font for terminals. Click one of the buttons to open a selection dialog where you can set the font family, style and size. For more information on the individual options, click Help.

In the Rendering section, you can change the way fonts are rendered on the screen. There are four basic options: Monochrome (monochrome rendering without any smoothing), Best Shapes (rendering optimized for precise character shapes), Best Contrast (rendering optimized for high contrast) and Subpixel Smoothing (taking advantage of LCD subpixel structure). Advanced options for display resolution, smoothing, hinting and subpixel order are available after clicking on Details.

Configuring Menus and Toolbars

You can configure the appearance and behavior of menus and toolbars. Click Computer+Control Center+Look and Feel+Appearance+Interface.

If you want icons to appear in menus, select Show icons in menus. Not all menu items have icons.

If you want to be able to define new keyboard shortcuts for menu items, select Editable menu shortcut keys. When this option is enabled, you can change an application shortcut key by placing the mouse pointer over the menu item you want to change and pressing the new key combination. To remove a shortcut key combination, place the mouse pointer over the menu item, then press <— or Del.

[Important]New Keyboard Combinations Can Change Defaults

If you assign a new keyboard combination that was previously assigned to something else, you are not warned. The previous assignment is removed and replaced by the new one. There is no automatic way to restore the default keyboard shortcut for a command. You must manually reassign the keyboard shortcut.

This feature does not maintain shortcuts that are normally assigned to all applications, such as Ctrl+C for copy. This might lead to inconsistencies in your GNOME applications.

Select one of the following options to specify how toolbar button labels display in your GNOME-compliant applications:

Text below icons

Displays icon labels below the icons for each button.

Text beside icons

Displays icons on the toolbar, with text beside the most important icons.

Icons only

Displays icons only, without any text labels.

Text only

Displays text labels on each button, without icons.

A preview of the selected option appears in the dialog.

Configuring the Screen Saver

A screen saver is a program that blanks the screen or displays graphics when the computer is not used for a specified amount of time. Screen savers originally protected monitors from having images burned into them. Now they are used primarily for entertainment or security reasons.

To configure a screen saver click Computer+Control Center+Look and Feel+Screensaver.

Figure 3.9. Screensaver Preferences Dialog

Screensaver Preferences Dialog

From the list on the left select the screen saver theme you like. You can also select Random for a random selection of a screen savers or just a Blank Screen. A preview of the currently selected screen saver appears on the right or, by pressing the Preview button, you can test the selected screen saver in a fullscreen mode.

Use the slider to specify the amount of time that the computer is to be idle before the screen saver is activated. If you want the screen saver to be activated after the specified time the Activate screensaver when computer is idle checkbox should be checked. If you also want the screen to lock automatically when the screen saver is activated the Lock screen when screensaver is active checkbox should be checked.

You can also access general power management options from here by clicking Power management.

Choosing a Theme

A theme is a group of coordinated settings that specifies the visual appearance of a part of the desktop. You can choose themes to change the appearance of the desktop. Use the Theme tab of the Appearance tool to select from a list of preinstalled themes. The list of available themes includes several themes for users with accessibility requirements.

To choose a theme, click Computer+Control Center+Look and Feel+Appearance+Theme.

Basic appearance and color settings for the desktop and applications are controlled using themes. You can choose from a variety of preinstalled themes. Selecting a style from the list overview applies it automatically. Customize opens another dialog where you can customize the style of single desktop elements like window content, window borders, and icons. Making changes and leaving the dialog by clicking Close causes the theme to switch to Custom Theme. Click Save As to save your modified theme under a custom name. The Internet and other sources provide many additional themes for GNOME as .tar.gz files. Install these with Install....

The Customize Theme dialog has the following tabs and options:

Controls

The controls setting for a theme determines the visual appearance of windows, panels and applets. It also determines the visual appearance of the GNOME-compliant interface items that appear on windows, panels and applets (such as menus, icons and buttons). Some of the control settings that are available are designed for special accessibility needs. You can select a control setting in the Controls tab of the Customize Theme dialog.

Colors

The colors of the text in windows, input boxes, selected items and tooltips (as well as color of the text background) can be configured in the Colors tab of the Customize Theme dialog.

Window Border

The window border setting for a theme determines the appearance of the borders around windows (window decorations). You can select the window border settings in the Window Border tab of the Customize Theme dialog.

Icons

The icon setting for a theme determines the appearance of the icons on panels and the desktop background. You can select the icon settings in the Icons tab of the Customize Theme dialog.

Pointer

The style and size of the mouse pointer can be configured in the Pointer tab of the Customize Theme dialog.

Procedure 3.1. Creating a Custom Theme

The themes that are listed in the Theme Preferences tool are different combinations of control settings, window frame options and icon options. You can create a custom theme that employs different combinations of options. To create a custom theme:

  1. Click Computer+Control Center+Look and Feel+Appearance+Theme.

  2. Select a theme from the list of themes and click Customize.

  3. Select the controls option you want to use in the custom theme from the list in the Controls tabbed page.

  4. Click the Colors tab, then select colors you want to use for windows, input boxes, text and other parts of the interface. Some control themes do not support setting custom colors.

  5. Click the Window Border tab and select the window frame option that you want to use in the custom theme.

  6. Click the Icons tab and select the icons option that you want to use in the custom theme.

  7. Click the Pointer tab and select the mouse pointer option that you want to use in the custom theme.

  8. Click Close+Save As.

    A Save Theme dialog is displayed.

  9. Type a name and a short description for the custom theme in the dialog, then click Save. The custom theme now appears in your list of available themes.

Procedure 3.2. Installing a New Theme

You can add a theme to the list of available themes. The new theme must be a compressed archive file (a .tar.gz file).

  1. Click Computer+Control Center+Look and Feel+Appearance+Theme.

  2. Click Install.

  3. Select the file and click Open.

  4. If you want to apply the new theme immediately click Apply New Theme. You can also Keep Current Theme.

Customizing Window Behavior

Use the Window Preferences tool to customize window behavior for the desktop. You can determine how a window reacts to contact with the mouse pointer or to double-clicks on its title bar and you can define which key to hold for moving an application window.

To customize window behavior click Computer+Control Center+Look and Feel+Windows.

Figure 3.10. Window Preferences Dialog

Window Preferences Dialog

When several application windows populate the desktop, the active window by default is the one last clicked. Change this behavior by activating Select Windows When the Mouse Moves over Them. If desired, activate Raise Selected Window after an Interval and adjust the latency with the slider. This raises the window a short time after the window receives focus.

Under Titlebar Action, it is possible to specify an action that is performed when the window's title bar is double-clicked. Select the desired action from the drop-down list. Possible actions include minimizing the window, maximizing it in one or both directions or rolling it up, leaving only the title bar visible. The default behavior is for the title bar to maximize in both directions.

Using the radio buttons, select a modifier key to press for moving a window (Ctrl, Alt or the Windows key).

Configuring File Management Preferences

The file management preference include settings for the GNOME file manager Nautilus as well as the settings for handling of removable media. You can access the preferences in the Control Center by clicking Computer+Control Center+Look and Feel+File Management or directly from Nautilus by clicking Edit+Preferences.

Figure 3.11. File Manager Preferences

File Manager Preferences

  1. On the Views tab define options for various Nautilus views. For example, select if Nautilus should show hidden files and backup files.

  2. On the Behavior tab define several options such as to open files or folders in Nautilus upon single or double mouse-click, or to include a Delete menu item in Nautilus which deletes files or folders directly from your file system instead of moving them to the trash.

  3. On the Display tab configure the date format and the way icon captions appear in Nautilus.

  4. Switch to the List Columns tab to configure the columns that appear in Nautilus, as well as the order in which they appear.

  5. Click the Preview tab to specify for which files to show previews in Nautilus and if folders should show the number of items they contain.

  6. Click the Media tab to specify actions that should be performed automatically whenever media such as audio CDs, video DVDs, blank disks, media players, digital cameras and other devices are connected. In general, you do not need to change these settings unless you want to change the behavior of a device when connected. If you attach a device for the first time and it behaves in an unexpected or undesired way, change the settings for the particular device.

  7. For more information on the available options click Help.

  8. Click Close when you are ready to apply changes.

Locking Desktop Functions

openSUSE ships with a graphical lockdown editor (pessulus package) that lets you disable (lockdown) certain desktop functions. This is useful if you want to restrict the actions that users can perform on a computer. For example, you might want to prevent command line operations on a computer that is for public use at a trade show.

If the pessulus package is already installed, start the Lockdown Editor from the main menu with Computer+Control Center+Look and Feel+Lockdown Editor or press Alt+F2 and enter pessulus.

Figure 3.12. General Lockdown Editor Settings

General Lockdown Editor Settings

When the Lockdown Editor starts, it tries to connect to the GConf mandatory configuration source (xml:merged:$prefix/etc/gconf/gconf.xml.mandatory). If you run pessulus as root, you have access to this configuration source and a lock icon is displayed next to the checkbox for each setting. Click the lock to specify if the setting is mandatory. If the setting is mandatory, regular users will not be able to change or override the setting. If you do not have access to the mandatory configuration source, the lock icon does not appear. In this case, all disabled settings are stored in the user's default configuration source and can be modified later using other tools such as gconf-editor or gconftool-2. For more information about GConf and mandatory configuration sources see Using GConf in the GNOME Desktop System Administration Guide .

Click a category on the left to view the settings for this category that can be disabled.

  1. To disable access to the command line, saving to disk and printing (or prevent the user from modifying print settings) set the relevant options in the General category.

  2. Use the options in the Panel category to lock down the panel, disable the panel applets you specify and disable the force quit, lock screen and log out options.

  3. Use the options in the Epiphany Web Browser category to control access to features in Epiphany.

  4. Use the options in the GNOME Screensaver category to lock the screen (when the screen saver goes active), enable or disable the logout (after a delay option in the unlock dialog box) and to enable or disable the switch user option in the unlock dialog box.

  5. For more information on the available options of each category, click Help.

  6. If all options are set according to your wishes, click Close to apply the changes.

Customizing the Main Menu

Use the Main Menu tool to customize the traditional GNOME main menu. The traditional GNOME menu is not enabled by default, but you can add it to your GNOME panel by right-clicking it and choosing Add to Panel+Traditional Main Menu+Add+Close. To customize the traditional GNOME main menu, use Computer+Control Center+Look and Feel+Main Menu.

Figure 3.13. Main Menu Editor

Main Menu Editor

The current main menu submenus are displayed on the left of the main window, the items belonging to the selected submenu are shown on the right. Groups in a submenu are nested below that submenu. To find an item, click the arrow next to a submenu in the Menus list, select the group containing that item and locate the item in the Items list.

[Note]Implications of Main Menu Changes

Changes you make to the main menu are not overwritten during a subsequent system update. Changes are applied after the latest menu view is generated.

Procedure 3.3. Editing the Main Menu

You can change the order in which items appear in the main menu, rename menu items, show (or hide) menu items, delete items from the menu or add new menu items. For example, you might want to place your frequently used applications at the top of the menu or at the top of their groups to make them easier to find. Adding new items to the main menu is helpful when you install an application, but it is also useful if you have other applications that do not currently appear on the menu. You can also add a directory, a link or another type of item to the menu.

  1. To move a menu item click the menu item in the Items list on the right and drag it to a new location in the menu. You can move the item to a new location in the same menu or drop it on an item in the Menus list (to move it to a new menu or group). Use the Move Up and Move Down buttons to change an item's location in the menu.

  2. To rename an existing menu item right-click the item in the Items list, select Properties and enter a new name.

  3. To hide an item (so it does not appear in the menu) deactivate the checkbox next to the item in the Items list. An activated checkbox indicates that the item is currently shown in the menu. When an item is hidden it still remains in the Items list and can be shown at any time you decide you want it to (re)appear in the menu.

  4. To delete an item from the Items list right-click the item and click Delete. If you want to show a deleted item in the menu again you must add it like you would a new application.

  5. To add a new item, proceed as follows:

    1. In the Menus list click the arrow next to the menu containing the group where you want to add the application, then select the group. The contents of that group appear in the Items list.

    2. Click New Item and select the Type of menu item to add. For example, to add an application select Application.

    3. Click Browse and select the item to add.

    4. Enter a Name for the new menu item.

    5. If you want a short description to appear in the main menu during a hover state enter the description in the Comment field.

    6. If you want to assign an icon to the new item, click the image frame on the left, then select an icon for the item. If you do not select an icon, the item appears in the menu without an icon.

  6. If you want to restore the default menu layout click Revert.

  7. If all options are set according to your wishes click Close to apply your changes.

    [Note]

    The first time you use the Main Menu application to edit the menu, changes do not take effect until your next login. Subsequent changes appear immediately.

Configuring Desktop Effects

Compiz is a compositing window manager for the X Window System that uses 3D graphics hardware to create fast compositing desktop effects for window management. Effects are implemented as loadable plugins. Compiz lets you turn your desktop into a rotating 3D cube, tile windows so they do not overlap and switch tasks while viewing live thumbnails. You can enable translucent or transparent windows, zoom in and out of the desktop screen, and use other window effects such as shadows, fading and transformations. You can also configure windows to snap to other windows and screen edges when they are moved.

Figure 3.14. 3D Desktop

3D Desktop

Enabling Desktop Effects

To enable desktop effects you need a graphics adapter capable of providing 3D support and the graphics driver that Linux uses to operate the graphics adapter. This driver must be able to handle OpenGL (or 3D) requests from the Linux kernel. If your configuration is compatible with desktop effects it will be enabled by default. If your configuration does not support desktop effects you will be warned upon activation.

To enable or disable desktop effects follow these steps:

  1. Click Computer+Control Center.

  2. Click Desktop Effects in the Look and Feel group.

  3. If your system is configured for desktop effects check Enable Desktop Effects. To keep desktop effects enabled press Yes in the dialog that opens. Otherwise, the desktop effects will be deactivated automatically in ten seconds.

    To disable desktop effects uncheck the Enable Desktop Effects option.

  4. The default set of desktop effects is now enabled. You can change the enabled effects and their settings on the several tabs of the Desktop Effects dialog or just select a Profile from the dropdown list. To activate the selected profile press the green button.

Modifying Desktop Effects

A simplified configuration tool for desktop effects is included in the Look and Feel section of GNOME Control Center. Open Desktop Effects tool from the main menu by clicking Computer+Control Center+Look and Feel+Desktop Effects.

Figure 3.15. Desktop Effects Configuration

Desktop Effects Configuration

  1. Use the Info tab to get general information about the current desktop effect settings.

  2. Use the options on the Animations tab to specify what happens when you open, close, focus or minimize windows.

  3. Use the options on the Effects tab to specify what type of Switcher to use. This is the desktop effect activated when switching between windows using the Alt+→| combination. This is where you can set various desktop effects like opacity of the desktop cube or wobbling windows.

  4. Use the options on the Desktop tab to configure the representation of virtual desktops you want to use (three dimensional Desktop Cube or planar Desktop Wall) and to set how many virtual desktops you want to use.

  5. Use the options on the Accessibility tab to configure screen and area zoom.

  6. Use the Edges tab to configure functions associated with active screen edges.

  7. For more information on the individual options, click Help.

  8. If all options are set according to your wishes, click Close to apply the changes.

[Note]Advanced Configuration Tool

An advanced configuration tool can be started from the Look and feel menu by clicking CompizConfig Settings Manager, or form a terminal emulator with command ccsm. This offers a greater selection of configuration options than the simplified tool in GNOME Control Center.

You can also use gconf-editor to change desktop effects settings.

  1. Click Computer+More Applications+System+GNOME Configuration Editor or press Alt+F2 and enter gconf-editor.

  2. Navigate to the apps/compiz/general and apps/compiz/plugins registry folders and make the desired changes.

  3. Click File+Quit to close the Configuration Editor.

Desktop Effects Shortcuts

The following table contains a list of the default keystrokes and mouse movements you can use to perform desktop effects. To change any of these shortcuts, see use the advanced configuration tool (CompizConfig Settings Manger). The shortcuts for zoom function can be configured in the Desktop Effects tool available from GNOME Control Center.

Table 3.1. Desktop Effects Shortcuts

Effect

Shortcut

Panoramic view of all desktops (if the desktop cube effect is enabled)

Ctrl+Alt+ (use the Left and Right arrows to scroll)

Rotate desktop cube (if the desktop cube effect is enabled) or switch desktops (if the desktop wall effect is enabled)

Ctrl+Alt+ or ( or keys can be used in case of desktop wall effect with multiple rows)

Rotate desktop cube manually (if the desktop cube effect is enabled)

Ctrl+Alt+left-click the desktop and drag the mouse pointer

Rotate desktop cube (if the desktop cube effect is enabled) or switch desktops (if the desktop wall effect is enabled) while keeping the current active window with you

Ctrl+Alt+Shift+ or

Switch windows (thumbnail view)

Alt+→|

Wobbly window (if the wobbly effect is enabled)

Left-click the window and drag

Zoom in manually (if the screen zoom is enabled)

Super key (Windows key) and scroll wheel up

Zoom out manually (if the screen zoom is enabled)

Super key (Windows key) and scroll wheel down

Zoom in area under mouse pointer (if the area zoom is enabled)

Shift, super key (Windows key) and scroll wheel up

Zoom out area under mouse pointer (if the area zoom is enabled)

Shift, Super key (Windows key) and scroll wheel down