If you want to use a window, it must be active. A window automatically becomes active when you open it, so that the application you opened is immediately ready to use. Only one window can be active at a time. The active window is the one into which you can type, and can be distinguished from the others because it has a different colored titlebar. (With the KDE default theme, the active window has a light blue titlebar, and the inactive windows have gray titlebars.)

When you want to work in a different window, you need to make it active. There are two ways to do this:

The first way to organize the windows on your desktop is to move them around. You can move windows so that they overlap other windows, or so that you can see the whole window. There are three ways to move a window:

You can make windows bigger or smaller, wider, or taller in one of two ways. Just use whichever you are most comfortable with:

If you just want to make a window as big as possible, so it takes up the whole screen, use the Maximize button, which is the second button from the right on the window titlebar. Clicking with the left mouse button on this button will make the window as big as possible in both directions; while clicking with the middle mouse button or the right mouse button will increase the window's size in only the vertical or horizontal direction, respectively.

When you need to keep a program open, but you do not want it to take up space on your desktop, you can minimize it or shade it. To minimize a window, click the Minimize button, which is third from the right on the window titlebar. The window will not be displayed, but the program is still running, and an entry for it appears in the taskbar on the panel. To display the window again, click on its entry in the taskbar. You can also use Alt + Tab : see the section called “Switching Between Windows”.

Shading windows is very similar to minimizing them, but this time, only the titlebar of the window is shown. To shade a window, double-click on the titlebar. To restore the window, just double-click on the titlebar again.

Sometimes you might have a whole lot of windows open and all over the place. By selecting to cascade windows KDE will automatically line them up as a succession from the top-left of your screen. To use this option use your middle mouse button on the desktop, and then select Cascade Windows .

By selecting to unclutter your opened windows KDE will attempt to use the maximum available space of the desktop in order to display as much of each window as possible. For example, should you have four windows open and you request that they be uncluttered, they will each be placed in a corner of the desktop, regardless of where they were originally. To use this option once again use your middle mouse button on the desktop and then select Unclutter Windows .

When you finish using an application, you will want to stop the application and close its window. Once again, you have the choice of a few options:

The simplest way to access the advanced window management facilities in KDE is to use a little known utility called kstart, which is included in KDE since version 2.1 kstart lets you control the way an application interacts with the window manager. The command is usually used to define special behavior for commonly-used applications, but it can also be useful for integrating non-KDE applications into your desktop.

Using kstart is easy: you simply put kstart and some options before a command. To begin, let's look at how we might use kstart to customize the behaviour of a KCalc window. The command we'll use is as follows:

% 



kstart

 
--ontop
 
--alldesktops
 
kcalc

With luck, the effect this command has should be fairly obvious - the kcalc window will stay on top of all the others and be visible on every virtual desktop. A feature that is less obvious is that this command will work with any NET compliant environment, not just KDE.

We can pass arguments to programs we invoke with kstart as normal, for example:

% 



kstart



--skiptaskbar
 
--desktop

1 xmessage'Hello World'

This command displays Hello World with xmessage and ensures that the window will be shown on the first virtual desktop and will be omitted from the taskbar. The fact that this program is written using the Xt toolkit rather than being a native KDE application does not cause any problem for kstart, hopefully this illustrates how kstart can be used to integrate foreign applications into your KDE desktop.

While you can use kstart to assign particular window settings, KDE also allows you to alter these -- as well as other similar settings -- from the program window itself. Simply select the leftmost button in the window titlebar (or just hit Alt + F3 once the window is focued), and then go to Advanced -> Special Window Settings... . As you can see, from here you change various things from its geometry upon startup, to whether it should have a border or not.

Now that we know how to customize the decoration of a window let's take a look at another aspect of the desktop: the system tray. The system tray is an area in which an application can display a small window. It is used to display status information or provide quick access to commands. A window that has an item in the system tray usually disappears from the task manager when minimised with the tray icon providing a replacement. Normally tray icons are specifically developed as part of an application, but as with window decorations, KDE provides a tool for changing this: ksystraycmd.

To begin with, we'll take the standard application KCalc and turn it into a system tray application. This is acheived with one simple command:

% 



ksystraycmd

 
--title
 'kcalc' kcalc

The icon shown in the tray is the one specified in the window hints and will be updated if the icon changes. The window title is shown as a tooltip if you hold the mouse over the icon. ksystraycmd follows standard KDE behaviour so the target window can be shown and hidden by clicking the tray icon, and a standard context menu is available.

---

---

To illustrate the other features of ksystraycmd, we'll use a more complicated example: a Konsole window tracking the .xsession-errors file (this is the log file that records what's happening on your desktop). To begin with, we'll simply look at how we can view this:

% 



konsole

 
--icon

log 
--caption
 'X Log' \ 

--nomenubar
 
--notabbar


--noframe
 \ 

-e
 tail -f ~/.xsession-errors

The --caption and --icon arguments are provided as standard by KDE applications. You can get a full list of these global options by running an application with the --help-kde and --help-qt parameters. Here we give our Konsole window the title 'X Log' and the icon “log”. You can use these options with any KDE application and as mentioned above, ksystraycmd takes account of these when creating the tray icon. The -e argument is specific to Konsole and tells it to run the less command. Despite its complexity, we can easily move this window into the tray with ksystraycmd:

% 



ksystraycmd



--hidden
 
--title
 'X Log' \
konsole --icon log --caption 'XLog' \ 
--nomenubar --notabbar --noframe \ 
-e tail -f .xsession-errors

In addition to being the most complex command we've used, this example demonstrates the --hidden option which starts the command with only the system tray icon visible. This example achieves our aim of providing quick access to the log file, but we can do things a little more efficiently if we only run the konsole process when it is visible. The command we use is

% 



ksystraycmd

 
--startonshow
 \
 --
icon
 log 
--tooltip
 'X Log' \ 
konsole --icon log --caption 'X Log' \
--nomenubar --notabbar --noframe \
-e tail -f ~/.xsession-errors

The addition of the --startonshow parameter tells ksystraycmd to start with only the tray icon visible (like the --hidden parameter), and to wait until the user activates the tray icon before running the target command. We've also used the --quitonhide parameter which tells ksystraycmd to terminate the target app whenever its window is hidden. Using both these parameters ensures that our Konsole tray icon doesn't waste resources when we aren't using it. Creating and destroying the target window as we do here prevents the standard icon and title handling of ksystraycmd from working, so we now need to specify the initial icon and tooltip explicitly too.

In all of our previous examples we've relied on kstart and ksystraycmd to figure out which window we want to affect, and unless we say otherwise, they assume that the first window to appear is the one we want. This policy is usually OK because we are starting the application at the same time, but it can fail badly when lots of windows are appearing (such as when you log on). To make our commands more robust we can use the --window parameter. This specifies the title of the target window. The following example uses the --window parameter to ensure that a particular konsole window is affected:

% 



kstart

 
--iconify
 
--window
 'kstart_me' konsole
--caption 'kstart_me' -e tail -f
~/.xsession-errors

Here we've used the tried and tested technique of specifying a title for both kstart and the target application. This is generally the best way to use kstart and ksystraycmd. The --window argument is supported by both kstart and ksystraycmd and can be regular expression (e.g. “window[0-9]”) as well as a particular title. (Regular expressions are a powerful pattern matching tool you'll find used throughout KDE.)

To move to a different virtual desktop, you can use Ctrl + Tab in the same way as you would use Alt + Tab to switch between windows (see the section called “Switching Between Windows”): Hold down Ctrl and then press Tab . A small popup window appears, showing the virtual desktops, with one highlighted. If you release Ctrl , KDE will switch to the highlighted virtual desktop. To select a different desktop, press Tab repeatedly, while holding down Ctrl . The selection moves through the available desktops. When the desktop you want to switch to is highlighted, release Ctrl .

You can move windows around your virtual desktops with the To Desktop item in the window menu: just select the desktop to which you want to move the window. You can make the window appear on all desktops with the All Desktops item.