LXDE:Questions

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General

What does the name LXDE mean?

  • LXDE is the abbreviation of Lightweight X11 Desktop Environment, and also LX means LinuX.

Why develop another desktop environment? Aren't there already KDE, GNOME, XFCE, and a lot of other well-made DEs? Why reinvent the wheel?

There are several essay writing service reasons for developing LXDE.

  • Though other desktop environments are well-made and powerful, they are in some ways big and slow, and eat up our RAM. LXDE aims to reduce the resource hunger.
  • Not everyone on this earth is rich. There must be a nice desktop environment for those who can't afford new fancy hardware, and we have the ability to help them.
  • Other desktop environments are too integrated, meaning reusing each part of them requires installing lots of dependencies.
  • If Windows 98 and XP work quite well on old machines, why should my GNU/Linux desktop need a >1.0 GHz CPU + >1GB RAM? We don't believe a usable desktop environment should require that much resource usage, so we built one ourselves.
  • Because reinventing the wheel is cool, and we love it! (Simply the best reason.)

I don't want a full DE, I only need XXX in LXDE, can I do that?

Each component of LXDE can be run independently, so you don't need to install the whole DE, if you don't like it. We deliberately keep all components desktop-independent and loosely-coupled. This is the main difference between LXDE and other projects.

Does LXDE automount plugged in removable devices (USB drives, Flash disks, etc)?

Yes, it does. It mounts devices from /etc/fstab automatically, others - removable drives and such - get mounted through HAL software.

I'm interested in developing a plugin for LXPanel. Are there any development docs I might be able to read?

There's no documentation for writing plugins at the moment, but feel free to look at the relevant source code: PluginClass struct from LXPanel's panel.h header file and an Example plugin.

How do I make an application autostart on LXDE launch?

You just add a .desktop file to ~/.config/autostart or add the commands to .config/lxsession/LXDE/autostart to have a program start for a specific user. Less commonly, for system wide startup, you can edit the file /etc/xdg/lxsession/LXDE/autostart.


What is the LXDE logo supposed to be? An evil sorcerer's hand?

It is a symbol of a bird flying fast. Moreover, the bird is light thus it can fly.

Huh? I don't see a bird.

Yes, no one sees the bird... It's a swallow flying to the top right.

What do you mean? An African or European swallow?

Huh? I... I don't know that.

Browser

How do I change my default browser?

  • As root:

# update-alternatives --config x-www-browser

  • Choose the browser of choice.
  • LXDE simply uses the application "x-www-browser", which in fact is a symbolic link to whatever browser the admin chooses. Same goes for x-terminal-emulator .
  • You can also use xdg-mime.

Keyboard/Mouse

How do I modify mouse/keyboard bindings?

Unfortunately, they are only configurable by hand, ie by editing the Openbox's rc.xml file.

How do I change the hotkeys?

Edit ~/.config/openbox/lxde-rc.xml with your favorite text editor.

  <keybind key="W-l">
    <action name="Execute">
      <command>xscreensaver-command -lock</command>
    </action>
  </keybind>

The W in "keybind key" stands for the Windows key on a keyboard, the l for the L key. For the changes to have effect you either have to restart the session or execute

# openbox --reconfigure


See also

How do I make my keyboard volume buttons work?

These could be tricky but if your keyboard is fairly standard the buttons will be handled already and just need to be mapped as above.

If your keyboard sends the following standardized keyboard events you can just copy and paste the lines below to the appropriate section in ~/.config/openbox/lxde-rc.xml.

Inside the <keyboard> element add the following

   <keybind key="XF86AudioLowerVolume">
     <action name="Execute">
       <startupnotify>
         <enabled>true</enabled>
         <name>amixer</name>
       </startupnotify>
       <command>amixer -c 0 set Master 5- unmute</command>
     </action>
   </keybind>
   <keybind key="XF86AudioRaiseVolume">
     <action name="Execute">
       <startupnotify>
         <enabled>true</enabled>
         <name>amixer</name>
       </startupnotify>
       <command>amixer -c 0 set Master 5+ unmute</command>
     </action>
   </keybind>
   <keybind key="XF86AudioMute">
     <action name="Execute">
       <startupnotify>
         <enabled>true</enabled>
         <name>amixer</name>
       </startupnotify>
       <command>amixer set Master toggle</command>
     </action>
   </keybind>

This will make up/down/mute use amixer (you probably have this if you have some alsa tools installed, check your package manager). It will step 5 points up and down and unmute where appropriate.

What about the Play, Stop, Previous and Next buttons?

These are a bit more tricky because the commands need to be customized for your preferred audio application. Here's an example section to add inside ~/.config/openbox/lxde-rc.xml to setup the Banshee media player.

Inside the <keyboard> element add the following

   <keybind key="XF86AudioPlay">
     <action name="Execute">
       <command>banshee --toggle-playing</command>
     </action>
   </keybind>
   <keybind key="XF86AudioStop">
     <action name="Execute">
       <command>banshee --stop</command>
     </action>
   </keybind>
   <keybind key="XF86AudioNext">
     <action name="Execute">
       <command>banshee --next</command>
     </action>
   </keybind>
   <keybind key="XF86AudioPrev">
     <action name="Execute">
       <command>banshee --previous</command>
     </action>
   </keybind>

Be reminded that this is just an example, check commands for other audio players, or check the the manual or --help of your preferred audio player.

My keyboard does not send standardized keyboard events

If you can not use the approach above try the following.

  1. Open a terminal
  2. Use the command xev
  3. When a white window appears press the volume up/down/mute and see the text scroll in the terminal. You are looking for something like this:
KeyRelease event, serial 36, synthetic NO, window 0x2200001,
   root 0x5b, subw 0x0, time 8796167, (204,-2), root:(1391,124),
   state 0x10, keycode 121 (keysym 0x1008ff12, XF86AudioMute), same_screen YES,
   XLookupString gives 0 bytes: 
   XFilterEvent returns: False

In the example the keyboard indeed does send standardized keyboard events (XF86AudioMute). Hopefully the keyevent you get can be used as is in the config file, please extend this section otherwise!

TIP: Use command xev | egrep -o "keycode.*\)" to see only the relative information.

Multimedia

Any suggestions for a lightweight audio/video player?

  • LXDE already has a minimalist XMMS2 based music player included, called LXMusic.

As for video, there is no player included so far - although lxine is being worked on - so you have to resort to third-party applications.

  • One of those is gnome mplayer. It uses MPlayer libraries, so it is capable of playing a broad range of formats. Its GUI is light, uncluttered and efficient for an undemanding user. With its small dependency footprint and an option of integration with internet browsers it is a great choice.
  • Another similar program is Whaaw! Media Player. It also has clean and straightforward interface (see for yourself), is written in Python and based on gstreamer multimedia framework.
  • The third alternative would be gxine, an easy frontend for the Xine libraries with a wide variety of supported media files.

Network

Which network manager is provided by LXDE?

What other network managers can I use besides LXNM?

Screen resolution

Which tool is used for configuring screen resolution in LXDE?

Window Manager

How can I use a window manager other than Openbox with LXDE?

  • Simply edit /etc/xdg/lxsession/LXDE/desktop.conf with a text editor, and replace openbox with your favorite window manager. Note: In lxsession < 0.4.0 you need to edit /etc/xdg/lxsession/LXDE/default instead.

Right click on the desktop renders a weird menu (aka where did my desktop icons go?)

You have (by accident?) chosen to show the right click menu from the window manager (or vice versa as you'll see). This is a feature in PCManFM.

  • Open the Preference dialog (click preferences in the edit menu)
  • Pick the desktop tab
  • Mark (or unmark) the checkbox next to "Show menus provided by WM when desktop is clicked" or, if this checkbox is not present, tick "Manage the desktop and show file icons"
  • Press OK and you should be done.

A window's top title bar is under the panel so I can't reach it, but I would like to move/close/minimize/etc the window.

Make sure you have ticked the "Reserve space, and not covered by maximized windows" property in the panel settings (right click on the panel, which is over the window -> Panel settings). Once that is checked, any windows created will not be placed under the panel.

To recover a window that is already under the panel, you can simply move the window down by holding the Alt key while left-mouse click-and-dragging anywhere in the window. Alternately, you can resize the window by holding down Alt and dragging inside the window with the right mouse button.

Another solution would be to use "Alt+Tab" to switch focus to the window, press "Alt+Space" to get the window menu, hover over "Layer" (or use the arrow keys) and in the popup menu choose "Always on top". This will make the window cover everything, even the panel, but has the downside that it will now obscure all other windows.

Where do I copy Openbox themes to?

Copy them to ~/.themes directory or /usr/share/themes.

LXLauncher

How do I change LXLauncher background/tab bar appearance?

LXLauncher uses (SVN revision 1128) three ways of defining it's GUI:

- for tab bar, GTK+'s own Resource file
- for dashboard (notebook) background color, hardcoded RGB color setting
- for border type and auxiliary buttons - ie "Go back", Appearance tool

First two are the toughest to change, so I will focus on them.

First, the resource file. To find lxlauncher's gtkrc file, look into "/usr/local/lxlauncher/" folder, where it is installed by default, and be sure you can see hidden files. If it is not there, look for it in all folders with "lxlauncher" in its name. When you get hold of it, open it in text editor, but with super user privileges, or you won't be able to save it. Making backup is advisable. With the file opened, you can start The important parts are the the color codes which can be changed. The color format is six digit hexadecimal - ie #344529 (for more information about GTK theming format, go here). There are three sections in the file.

1. style section. This one has only one color setting; it's the one that changes the color of tab bar background:

What changing this color does (just an example):

Tabbarbackgroundone.jpg Original Tabbarbackgroundtwo.jpg Changed

2. second style section. It has two color options.

The first causes change of text color on currently chosen tab in tabbar, application names on "notebook" surface and subpage location (here, green): Tabbartwo.jpgOriginal

Tabbarone.jpgChanged

The second color changes the look of application text on mouseover:

Mouseoverone.jpgOriginal

Mouseovertwo.jpgChanged

3. style section. It has three - just the uncommented - options.

First one changes background of currently selected tab, background of subpage location, and the border of "notebook" surface:

Tabselectedbackone.jpgOriginal

Tabselectedbacktwo.jpgChanged

Second one changes text color of unselected tabs:

Unselectedtabsonlyone.jpgOriginal

Unselectedtabsonlytwo.jpgChanged

The last one changes the background color of currently unselected tabs:

Backunselone.jpgOriginal

Backunseltwo.jpgChanged

A nice point&click online color chooser (with gtkrc hex color format) is located here.

Second, the background defined in the source code. This manages the "notebook" foreground (where application icons are stationed). In the LXLauncher lxlauncher.c source file search for this string:

 cairo_set_source_rgb(cr, 184.0/256, 215.0/256, 235.0/256);

The fractions are the corresponding RGB values from 0 - 255 (here normalized to 1). The default color looks like this: Foreground.jpg

If we change the values to this:

 cairo_set_source_rgb(cr, 0.0/256, 214.0/256, 0.0/256);

we get the following view:

Foregroundnew.jpg

LXMusic

How do I pass arguments to LXMusic in terminal (eg add a file to playlist, play file, etc)?

You can't do that directly. LXMusic is only a frontend to XMMS2 client-server audio player; instead you should use the CLI client, which comes bundled with the package by default.

basic cli commands:

# xmms2 add filename.ogg

# xmms2 radd directory/with/files/


LXPanel

How do I add custom sub-menu and/or launcher to LXDE's main menu?

For editing the menu you can use a third-party program called Alacarte. It is written in python and makes use of python-xdg library. However, if you don't want to use it and make changes to the menu manually, you'll have to edit the per-user menu configuration file. Usually, it resides in ~/.config/menus, under the name of "lxde-applications.menu". It should be something like (if empty or does not exist, just copy & paste the following text):

<!DOCTYPE Menu PUBLIC "-//freedesktop//DTD Menu 1.0//EN" "http://www.freedesktop.org/standards/menu-spec/1.0/menu.dtd">
<Menu>
      <Name>Applications</Name>
      <MergeFile type="parent">/etc/xdg/menus/lxde-applications.menu</MergeFile>
</Menu>

Now, if you want to add, say the file README.desktop launcher under Accessories menu, change the upper text to the following:

<!DOCTYPE Menu PUBLIC "-//freedesktop//DTD Menu 1.0//EN" "http://www.freedesktop.org/standards/menu-spec/1.0/menu.dtd">
<Menu>
	<Name>Applications</Name>
        <MergeFile type="parent">/etc/xdg/menus/lxde-applications.menu</MergeFile>
        <Menu>
	      <Name>Accessories</Name>
	      <Include>
                        <Filename>README.desktop</Filename>
	      </Include>
       </Menu>
</Menu>

To add, say, README.desktop to a "Accessories" sub-menu "MyMenu", change to the following:

<!DOCTYPE Menu PUBLIC "-//freedesktop//DTD Menu 1.0//EN" "http://www.freedesktop.org/standards/menu-spec/1.0/menu.dtd">
<Menu>
	<Name>Applications</Name>
        <MergeFile type="parent">/etc/xdg/menus/lxde-applications.menu</MergeFile>
        <Menu>
			<Name>Accessories</Name>
                        <Menu>
			           <Name>MyMenu</Name>
                                   <Directory>MyMenu.directory</Directory>
			           <Include>
			                       <Filename>README.desktop</Filename>
			           </Include>
                        </Menu>
        </Menu>
</Menu>

To add it to other LXDE provided menus, change "Accessories" accordingly. Note the "MyMenu.directory" line. This is the file that provides the directory name, icon, comment and other properties. If the file does not exist, you'll have to create one; copy it to "~/.local/share/desktop-directories" directory, with the (minimal) content of:


          [Desktop Entry]
          Encoding=UTF-8
          Icon=/path/to/icon
          Name=MyMenuOrSimilarString

Simply add an application

If all you wish to do is add an application to the provided menus you do not need to edit the menu files. Simply create a .desktop file as above and save it to "~/.local/share/applications". You may have to create this directory.

Eg .

>vi ~/.local/share/applications/idea.desktop

Example .desktop file:

[Desktop Entry]
Type=Application
Icon=/home/jeremy/dev/tools/idea/idea-IU-95.627/bin/idea128.png
Name=Intellij Idea
Comment=Java Ide
Categories=Utility;Development
Exec=/home/jeremy/bin/idea.sh %U
StartupNotify=true
Terminal=false

The Categories property tells LDXE which menus the item should appear in.

For more information on creating/editing menus and fine grained settings, please read Freedesktop's Desktop file and Menu specification.

How do I edit my application launch icons?

  • As of SVN revision 975 you are able to right click on desktop shortcut entry in the LXPanel menu, and click "Properties". This invokes LXShortcut desktop file editor; with it you can then edit the file to your needs, or
  • You can edit the <app name>.desktop files in the /usr/share/applications folder or in the "application" subfolder of folders defined by "$XDG_DATA_DIRS" environment variable (to see what they are invoke command "echo $XDG_DATA_DIRS" from terminal). In the Icon line put the path and the icon name as you like.(eg. Icon=/usr/share/pixmaps/<icon.png> the icon file can be .svg also)

How do I edit the colour of the tasks in the panel?

  • Just right click on the panel -> panel preferences -> panel extensions -> choose panel/taskbar, then click on edit.

There you can change different preferences, activate flat Buttons. It will look better. Custom colours of the tasks would require gtkrc editing.

The tray clock numbers color is black, my wallpaper is also very dark and panel is transparent and the time is not seen clearly. Where do I change color of DC's numbers?

Do right click on LXPanel -> Panel settings -> tick "Custom color" and preferably choose brighter color with the color chooser next to it.

I would like to change the LXDE icon in the start menu. How do I do it?

By default, it is usually enough to replace icon "lxde-icon.png" in /usr/share/lxde/images/ folder with your own. If the aforementioned icon does not exist, locate the panel's config file (just "panel") - most likely location is "/home/USER_NAME/.config/lxpanel/LXPANEL_PROFILE/panels/" directory. In it, look for line "type = menu" and underneath the location of the icon it is being used in the menu.

Since SVN version 969, there is an easier way to do it - now you can change menu icon on right clicking it, choosing "Menu properties" and selecting it in icon browser or by manually typing in the location of the wanted icon:

Menu icon change.png

LXShortcut

What do I do, if launching it in terminal doesn't show anything?

You must provide LXShortcut with at least one of two arguments:

"-i <input>" - stands for which .desktop file you want to edit or
"-o <output>" - to which file you would like to create a new desktop shortcut

If providing these two arguments still doesn't show anything, try another: "--display=DISPLAY" where DISPLAY is in form of {hostname}:display_number{.screen_number}.

PCmanFM

Does PCmanFM support ftp/sftp/other protocols for remote folder browsing?

Yes, this is supported in 0.4 branch of PCmanFM. Unfortunately, most Linux distributions include the 0.5 branch, which, albeit it's stability, does NOT have such capability. Furthermore, the released packages are quite old; usage of SVN version is preferred.

How do I make PCManFM work with multiple monitors?

Separate X screens

You should modify startup scripts to run pcmanfm on second display. See the example:

# DISPLAY=:0.1 pcmanfm -d 2>1 &


You also should start some window-manager on the second screen. See the example:

# DISPLAY=:0.1 openbox 2>1 &


Starting a separate X server and use PCManFM on it

   #!/bin/sh
   # start Xnest
   Xnest :1 -name "LXDE:test" -geometry 800x600 &
   export DISPLAY=:1
   export HOME=/home/test
   export LANG=en_US.utf8
   export SHELL=/bin/bash
   export TMPDIR=/tmp/
   export PATH=/bin:/usr/bin:/sbin:/usr/sbin:/usr/bin/perlbin/site:/usr/bin/perlbin/vendor:/usr/bin/perlbin/core:/opt/qt/bin
   # No core files by default
   ulimit -S -c 0 > /dev/null 2>&1
   export USER="`id -un`"
   export LOGNAME=$USER
   export HOSTNAME=archtower
   export HISTSIZE=1000
   # Keyboard, bell, display style: the readline config file:
   if [ -z "$INPUTRC" -a ! -f "$HOME/.inputrc" ]; then
       INPUTRC=/etc/inputrc
   fi
   export PS1="[\u@\h \W]\$ "
   # load the keymap, change to your needs
   loadkeys /usr/share/kbd/keymaps/i386/qwertz/de-latin1-nodeadkeys.map.gz
   
   # set the new X server and start a session
   xsetroot -display :1 -solid black &
   # this will run pcmanfm as user test
   exec sudo -u test pcmanfm &

Development

How do you justify calling LXDE "lightweight" and "fast" when it uses Gtk 2? This toolkit is among the fattest and slowest available. Why not FLTK or FOX?

  • Nobody wants to use it if there are better toolkits which really fit the need. Using gtk+ 2 is a hard choice. The i18n support of other toolkits is not very good. Apart from lightweight & fast, usability is important at the same time.
  • For English users, there is no problem, but can FLTK and FOX handle bi-directional text rendering? I know they already supported utf-8, but utf-8 is only the minimal requirement to be internationalized. Input methods, and many other issues should be properly-handled.
  • So, the only toolkits with really good i18n supports are gtk+ 2 and Qt among which gtk+ 2 is lighter.
  • FLTK and FOX unfortunately are not the right toolkits currently. Hopefully FLTK and FOX can have better i18n support, and we can start using them. I know FOX 1.7 has improved i18n support, but that's not complete yet. Besides, these toolkits lacks some advanced features and supports to freedesktop.org standards.
  • In some restricted environments, like embedded systems, competent C++ compilers are not available, and programs with C++ toolkits cannot be used. So gtk+ is a better choice if portability is important. Writing programs with gtk+ is really a pain, though.

Plans to migrate to GTK3+?

Lubuntu Plans a migration to GTK3, but..the project...... ..... ..... Please a developer put the ansewer her, please

Where can I find the bug tracker for LXDE components?

The LXDE components share a bug tracker in the LXDE project at Sourceforge. For PCManFM and libfm the bug tracker in the PCManFM project at Sourceforge is used.