Bug 333176

Summary:	ctrl-space keybindings don't work
Product:	[I don't know] kde	Reporter:	Glenn Holmer <cenbe>
Component:	general	Assignee:	Unassigned bugs mailing-list <unassigned-bugs>
Status:	RESOLVED NOT A BUG
Severity:	normal	CC:	cfeck, lists, volkangezer
Priority:	NOR
Version:	4.12.97
Target Milestone:	---
Platform:	Ubuntu
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:

Description Glenn Holmer 2014-04-07 19:49:58 UTC

Ctrl-space shortcuts in applications don't work, for example in the NetBeans Java IDE for code completion, or in emacs (in a terminal) to set the mark.

Reproducible: Always

Steps to Reproduce:
for NetBeans:
1. Install Oracle's JDK and the NetBeans IDE.
2. Edit a Java file and type ctrl-space for code completion.

for emacs:
1. Install "emacs" package.
2. Open a text file with "emacs -nw".
3. Type ctrl-space to set the mark, then cursor-down to select a line, then alt-w to copy the line.
Actual Results:  
for NetBeans:
No effect, but alternate keybinding ctrl-\ works correctly.

for emacs:
Error message "The mark is not set now, so there is no region." If I drop down to a
console (ctrl-alt-F1) and run emacs there, the key combination works normally.

Expected Results:  
for NetBeans:
Both ctrl-space and ctrl-\ should invoke auto-completion.

for emacs:
Line should be copied into the buffer without an error message.

Ubuntu 14.04 "Trusty Tahr" daily build with all current updates applied.

Comment 1 Christoph Feck 2014-04-07 22:12:46 UTC

What happens if you press Ctrl+Space? If applications do not see the combination, it is assigned as a global shortcut by some other program.

Comment 2 Glenn Holmer 2014-04-07 23:30:19 UTC

I went through the entire list of shortcuts in the "Shortcuts and Gestures" dialog of System Settings and did not find a binding for ctrl-space. Typing that combination by itself when the desktop has focus has no apparent effect. Is there a better way to see if there is a binding I didn't find?

Comment 3 Glenn Holmer 2014-04-12 09:55:32 UTC

I found what's causing it. Settings / Input Method shows that this combination is bound to "select next input method". However, when I change it to ctrl-alt-space, the next time I run the configurator, I get a dialog that says:

Current configuration for the input method:
 * Active configuration: missing (normally missing)
 * Automatic configuration: ibus (normally ibus or fcitx or uim)
 * Number of valid choices: 2 (normally 1)
The configuration set by im-config is activated by re-starting X.
Explicit selection is not required to enable the automatic configuration if the active one is default/auto/cjkv/missing.
  Available input methods: ibus xim
Unless you really need them all, please make sure to install only one input method tool.

Comment 4 Christoph Feck 2014-04-20 16:23:45 UTC

I am not sure I understand comment #3. After your investigations, do you still see a bug in KDE software? If yes, could you be more specific to what the actual error is?

Comment 5 Glenn Holmer 2014-04-20 20:34:14 UTC

After re-assigning the Input Method key, shouldn't I see an active configuration? In the dialog that follows, I see this:

"Do you explicitly select the user configuration?
* Select NO, if you do not wish to update it. (recommended)
* Select YES, if you wish to update it."

Selecting YES results in the same dialog next time I run Settings / Input Method.
Maybe I don't understand what this utility it supposed to do. If that's normal behavior, then the bug can be closed, since ctrl-space is no longer overridden. On the other hand, I have no idea what I might have done to get in that situation in the first place.

Comment 6 Christoph Feck 2014-04-20 21:11:47 UTC

What is "Settings / Input Method" anyway? fcitx? KDE developers did not develop it, so if unsure, ask in a forum of your distribution who is responsible for this module.

Marking as invalid, unless you can provide more information where KDE software has a bug.

Comment 7 Glenn Holmer 2014-04-20 21:25:48 UTC

It is im-config. You are right, as far as I can see it is Debian- or Ubuntu-specific.

Comment 8 Werner Mollentze 2014-06-24 10:04:00 UTC

Just a note to help other users resolve this (potentially annoying) problem.

After upgrading to 12.04, I found that the Ctrl+Space keyboard shortcut was assigned to IBus' "Next Input Method", causing IBus to listen and capture Ctrl+Space while editing text.

To clear the assigned IBus keyboard shortcut (and thus resolve the Netbeans editor Ctrl+Space code completion popup problem) you can edit IBus Preferences by running ibus-setup from the command prompt. Then delete the keyboard shortcut, or assign a different shortcut.