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16.3. The KDE Control Center

The KDE Control Center contains a number of configuration tools, called modules, that allow you to configure and view information about your system. You can configure the desktop, the window manager, input devices, and any other important part of your system here. The Control Center is split into two windows: the left window shows a hierarchical list of installed modules, and the right window displays them when they are selected. (You also have the option to display each module in its own window. Go to the Options menu and click the Swallow Modules entry, which is checked by default, to unselect it.)

16.3.1. Applications

The Applications modules set preferences for important KDE components, such as the login manager, kfm, and the panel. Login manager (root only)

The KDE login manager is the program that controls the graphical login screen. This module lets you configure the graphical style of the login screen, as well as set some default display options, such as prelisted users and available session environments.

The Appearance tab lets you edit the greeting string displayed on the login screen and choose a logo. A drop-down box offers you a choice of the GUI style of the login screen: either Windows or a Motif style. The Language option on this tab lets you select the default character encoding for the login manager.

The Fonts tab lets you choose the font style and size for the Greeting, Fail, and Standard screen messages. Select which type you want to configure from the drop-down list and click the Change Font button. The pop-up window shows a list of available fonts and lets you set the point size. Click the OK button to close the pop-up window. The font you have chosen is displayed in the Example area of the tab.

The Background tab lets you select the background for the login screen. Like the desktop background, you can choose a color or wallpaper to use.

The Users tab allows you to show a list of users on the login screen. The users are listed by username with a logo above the login boxes. A user can simply click her logo to automatically enter her name into the login box, but she still must supply her password. The tab contains listings for all users, selected users, and no-show users. You can select names from the lists and use the arrow buttons to move them from one box to another. Two options are available for who to display on the login screen. You can place names in the selected users list and click the Show Only Selected Users button. Or, you can edit the all users list and click the Show All Users But No-Show Users button. No-show users are user IDs that are used to control access-restricted system resources (e.g., root, news, and nobody).

The Sessions tab configures session settings. The drop-down list at the top sets who is allowed to shut down the system. You have the choices None, All, Root Only, and Console Only. The Commands section allows you to set the commands used for shutdown and restart. The Session Types section configures the list of session types that a user can log into from the login screen. The Default list contains the various environments that are installed on your system such as KDE and GNOME. You can add a new type or remove a type from the listing. Web browser

This module configures settings used for kfm's web browsing functionality.

If your system is behind a firewall, you may need to use a proxy server for HTTP and FTP services. The Proxy tabs lets you enable the use of a proxy and configure it. Check the Use Proxy box, and supply the hostname or IP address for the proxy server and the port number to use. Some sites may not work properly when accessing them through a proxy server. The No Proxy For: box lets you specify a list of hostnames and domains that will not be accessed via the proxy server.

The HTTP tab sets a few of the parameters sent in HTTP requests by the browser. The Accept Languages box contains a list of two-letter abbreviations used to indicate the language that the browser can accept. The abbreviations, like en for English and fr for French, can be comma-or-space separated. The order of the list determines the preference of language. The Accept-Language HTTP request header is configured with this setting.

The Accept Character Sets box contains a list of character sets that the browser is capable of receiving. (This sets the Accept-Charset HTTP request header.) The list can accept the standardized character set strings, separated by spaces or commas. The Assume HTML button tells the browser to render as HTML documents whose type is not fully specified from the server response header.

The User Agent tab allows you to specify the user-agent string reported by the browser for sites that may not recognize kfm, or anything that's not a major commercial web browser. The user-agent string contains the name and version number of the client program making the request. The default for kfm at the time of this writing is "Konqueror/1.1.2". To set a different string for a specific server, type the server name in the On Server box and supply the user-agent string in the Login As box. Click Add to save this setting. All settings will be listed in the Known Bindings box. If you want to remove a setting, select it from the list, and click the Delete button.

The Cookies tab configures how kfm will manage cookies. Cookies are not used at all unless you check the Enable Cookies box at the top of the tab. You should set the default cookie policy to either accept all cookies, reject all cookies, or prompt for action each time a cookie is received. You can specify the policy for individual domains as well. Type the domain into the Change Domain Accept Policy box, and specify Accept, Ask, or Reject for the policy. Click the Change button, and the setting is saved. You will see it listed in the Domain Specific Settings list. If you would like to remove a setting, select it from the list and click the Delete button. Panel

The panel configuration module controls the panel, the toolbar, virtual desktops, and the disk navigator.

The Panel tab contains settings for the location of the panel. You can choose to place it at the top, bottom, left side, or right side of the screen by clicking the appropriate radio button. Three settings are available to set the size of the panel to either Tiny, Normal, or Large. You also have choices for how the taskbar is displayed. If you do not want the taskbar to be displayed at all, click the Hidden radio button. If you want the taskbar displayed fully across the top or bottom of the screen, click either the Top or Bottom button. If you choose the Bottom option, the taskbar will appear just above the panel. Finally, the Top/Left option displays the taskbar at the top-left corner of your screen, with window buttons stacked on top of each other.

The Options tab, shown in Figure 16-7, is divided into three sections. The Menu Tooltips section contains a button to enable tooltips to be shown on menu items. You can use the slider to set the amount of time that the pointer is held over the item before the tooltip appears. The Visuals section allows you to set the panel and taskbar to autohide (i.e., disappear when not being used). Enable these settings by clicking the Auto Hide Panel and Auto Hide Taskbar buttons. Each option has two slider settings if autohide is enabled. The Delay slider sets the amount of time after use (after the pointer has left the panel/taskbar) that the panel will reduce. The Speed slider sets how fast or slow the panel or taskbar will open and hide. The Animate Show/Hide setting enables the panel to use a sliding visual effect when you show or hide it with its side arrow buttons. The slider sets the speed of this animation.

Figure 16-7

Figure 16-7. Panel options configuration

The Options tab contains the following additional settings:

Personal Menu Entries First

Check this box to display your personal menu section instead of the default system menu at the top of the main menu. The system menus will be contained in the default submenu.

Menu Folders First

Check this box if you want folders to appear at the top of your personal menu, above individual items. This setting can be overridden by customizing the menu order with the menu editor.

Clock Shows Time in AM/PM Format

This option enables AM/PM designation on your panel clock. Otherwise, the hour listing will range from 00 to 24.

Clock Shows Time in Internet Beats

This option allows you to have the panel clock display the Swatch-created time format, which divides a day into 1000 beats, in the GMT+1 time zone.

The Desktops tab sets the number of virtual desktops you can divide your workspace into. The default is 4, and you can use up to 8. The Visible slider selects the number of desktops (you can choose only even numbers). The desktops are listed, numbered 1 through 8. If enabled, the desktop listing has a usable textbox next to it. You can type in a label for the desktop that will be used in the pager display on the panel. The Width slider sets the width of the pager buttons shown on the panel.

The Disk Navigator tab allows you to configure the disk navigator shown on the menu and the taskbar. The History section of this tab has two buttons: Edit Personal and Edit Shared, which allow you to edit the contents of the Personal and Shared sections of the disk navigator from the file manager.

The Edit Personal button opens kfm in the ~/.kde/share/apps/kdisknav directory. This folder in the user's home directory contains kdelnk files for the items displayed in the Personal section of the disk navigator. The Edit Shared button opens /usr/share/apps/kdisknav in kfm, which contains kdelnk files for the contents of the Shared section. This directory can be edited only by root; other users will have this button disabled.

Additional options set the number of folder entries and file entries displayed in the Recent section of the disk navigator and the maximum number of files that can be displayed in a folder.

The Options section of the Disk Navigator tab contains buttons for the following settings: Show Dot Files (which shows the hidden files that start with a dot), Show Shared Section, Show Recent Section, Show Personal Section, Show Option Entry, and Ignore Case When Sorting. There is also a selection for the default terminal application to use.

16.3.2. Desktop

The Desktop modules set preferences for the visual display of your environment. You can individually set the background, fonts, or window colors or use the Theme Manager to configure all of the settings from an installed package. Theme manager

Themes provide an overall visual style to your desktop, instead of you having to configure items individually. A theme can determine the color scheme of windows, the font styles, icons, the background, and even sound events for your desktop. A couple of themes are installed by default with KDE, and many more are available for downloading at http://kde.themes.org.

TheInstaller tab, shown in Figure 16-8, lists the themes you have installed on your system. These include global themes, which are stored in the /share/apps/ kthememgr/Themes directory of your default KDE directory, and local themes, stored in ~/.kde/share/apps/kthememgr/Themes in your home directory. Local themes are themes that are installed or customized by the user and stored in his home directory. The user is able to edit and save local themes. Global themes cannot be altered by individual users.

Figure 16-8

Figure 16-8. Theme Manager installer

If you select a theme from the list, a sample desktop image using the theme is displayed on the tab, with a short text description. If you would like to apply a new theme, select from the list and click the Apply button. The selected theme will be copied to the user's theme manager work directory (~/.kde/share/apps/kthememgr/Work).

You can also manage installed themes on the Installer tab. To install a new theme that you have downloaded, click the Add button. Specify the filename and location of the theme's .tgz file in the pop-up dialog box and click OK. The Save button lets you save the currently configured theme as local or save a global theme as local. The Save As button saves the currently configured theme as a separate local package without altering the original theme. The Create button works similarly, allowing you to copy your current working theme as a new local theme package. The Remove button deletes a local theme or inactivates a global theme.

The Contents tab shows the components that are configured by a theme. A theme may not have settings available for all the listed components. If a theme configures a specific component, it is listed as available. Otherwise, the component is listed as empty. Use the checkboxes to select which theme components you want to use. If you choose to not activate a specific component, information on that component from a previous theme will be used if its information is still in the theme manager work directory. If you don't want this to happen, activate the component, even if it is listed as empty, and default settings will be used.

The About tab shows you author and version information for a selected theme. Style

The Style module contains a couple of settings for the display of windows and icons. Draw Widgets in the Style of Windows 95 enables window components to have a similar look to those used in Windows. The Menu bar on Top of the Screen in the Style of MacOS setting places a window's menu bar across the top of screen. Apply Fonts and Colors to Non-KDE Apps will apply the styles you've chosen to programs that were not written for KDE.

The Icon Style section allows you to set the size of icons to either Normal or Large. You can set the size for icons in the following locations: on the panel, in the file manager and desktop, and at all other locations.

16.3.5. Keyboard Shortcuts

You can choose the scheme used for shortcuts by selecting the KDE defaults or the current scheme if you have customized the shortcuts. The bottom section of the tab allows you to edit the selected keyboard shortcut. You can choose no key for the action, the default key, or a custom key. If you want to customize a key, check the box for the modifier you want to use (Shift, Ctrl, or Alt), or unselect all of them if you don't want a modifier. Then click the key button and press the key on the keyboard that you want to use. Click the Save Changes button if you want to save the change to the current scheme.

16.3.7. Window Behavior

The modules contained in this section allow you to set the look and functions of window titlebars, mouse button actions, and focus and placement policy. Advanced

The Keyboard and Mouse section of the Advanced tab contains the following settings:

Ctrl-Tab walks through desktops

This checkbox sets the Ctrl-Tab key combination to switch through your virtual desktops. It is checked by default.

Alt-Tab is limited to current desktop

This checkbox restricts the action of the Alt-Tab key combination to switch through windows on the current desktop only. It is checked by default.

Alt-Tab mode

This setting describes the style of using Alt-Tab to switch through windows. The KDE setting uses a graphical style. When you press Alt-Tab, a window appears indicating the current window and other available windows. The CDE setting switches directly without a graphic.

Grab the Right Mouse Button

This setting is on by default. It sets the control of the right mouse button to KDE by default. Some non-KDE applications require control over the right mouse button. If you need control for these applications, unselect this setting.

The Filters section of the Advanced tab contains settings that let you customize window styles or functions for application windows based on their titles or classes. The drop-down box contains a list of settings that you can define for a filtered window. After the Windows Will label, you can choose the following settings:

  • Have tiny decorations

  • Have no decorations

  • Never gain focus

  • Start as sticky

  • Be excluded from session management

Select a setting, then define the window in the next section, which begins with If They Match the Following. Here you have two boxes, Titles and Classes. You can define one or both properties. Put the title of the application window in the Title box and the application's class name in the Classes box. (This is usually the capitalized name of the application, preceded by an X, for example, XEmacs for an Emacs window.) You can specify more than one title or class for a window setting. Buttons

This module configures the layout of buttons that appear on the titlebars of windows. There are five buttons: minimize (dot), maximize (square), sticky (pushpin), close (X), and menu (dash or application-specified icon). Each button has three placement options, specified by radio buttons: left, right, or off. You can place no more than three buttons on one side of the titlebar. Mouse

This module configures the actions of mouse buttons on the various window components. Drop-down boxes contain several options, such as raise or lower, for the left, middle, and right buttons, as shown in Figure 16-9. Select from the following options in each category:

For active titlebars and frames



Operations menu

Toggle raise and lower

For inactive titlebars and frames


Activate and raise

Activate and lower

For an inactive inner window

Activate, raise, and pass click

Activate and pass click


Activate and raise

For titlebars and frames of inner windows


Toggle raise and lower





Figure 16-9

Figure 16-9. Mouse button configuration settings Properties

This tab sets windows options and the placement and focus policy. The Windows section of the tab has three settings:

Vertical maximization only by default

Check this box to cause the maximize window command to expand a window only to the full screen height, but leaving its width unchanged.

Display content in moving windows

Check this box to enable the display of window contents when the window is moved.

Display content in resizing window

Check this box to enable the display of window contents when the window is resized.

Resize animation

This slider controls the animation of windows that are maximized or minimized. Setting the slider all the way to the left (None), disables animation, and windows will maximize or minimize instantly. You can set the speed of the animation faster by setting the slider farther to the right.

The Placement Policy section of the tab contains a drop-down box with five options for determining the initial placement of new windows on the desktop:

Smart (default)

This setting uses a placement scheme that attempts to keep windows as uncluttered as possible.


This setting attempts to place windows in a cascaded pattern, with a set of offset positions available on each desktop.


This setting enables the "allowed overlap" setting. If a window can be placed on the desktop without overlapping another by the specified percentage, it will be placed automatically. If the overlap exceeds the setting, you will be given manual control of the window placement.


This setting randomly places a new window on the desktop.


This setting opens a window with the mouse pointer activated in move mode on the titlebar. Move the window to the desired position and click once to place the window.

The Focus Policy section sets the policy for giving a window keyboard focus and an active titlebar. The drop-down box contains four focus styles. The default is Click to Focus, which gives a window the keyboard focus and brings it to the foreground only when you click on it. The remaining settings follow the mouse and activate the Auto Raise and Click Raise options.

Click to focus

The default focus policy requires a mouseclick in a window to give it focus and raise it (bring it to the foreground). This setting uses a graphical Alt-Tab style to switch through windows on a desktop.

Focus follows mouse

This setting causes a window to receive focus when the mouse pointer enters it. The window will not come to the foreground unless the Auto Raise button is checked. The window will maintain focus until the pointer enters another window.

Classic focus follows mouse

This setting is similar to the Focus Follows Mouse setting, except that the window loses focus when the mouse pointer moves out of it. If the pointer is not in a window, no window has focus. Also, Alt-Tab switches directly among windows, without showing the graphical listing of windows.

Classic sloppy focus

This setting is similar to Focus Follows Mouse, with focus remaining in a window even when a mouse pointer leaves it. The only difference is that the nongraphical Alt-Tab style is used.

For any of the nondefault settings, you need to check either the Auto Raise or Click Raise boxes to be able to raise windows to the foreground. Click Raise raises a window when you click on it. Auto Raise raises a window after a short delay, which you can set with the Delay slider.

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