IDEA-Which-Key

IdeaVim extension that displays available keybindings in a popup similar to vim-which-key

Installation

JetBrains Marketplace

Install the plugin from the official JetBrains Marketplace

Withing Intellij go to File -> Settings -> Plugins -> Marketplace search for "Idea Which Key" and click on Install

Manual Installation

To build and install the plugin directly from source run the Gradle task buildPlugin

Afterwards you find the built jar under /build/libs

Install the jar in Intellij via File -> Settings -> Plugins -> Install Plugin from Disk...

Activation

Since this is an extension plugin for IdeaVim you have to activate it explicitly within your .ideavimrc file
Furthermore you should either disable the timeout option or increase the value for timeoutlen

set which-key

" disable the timeout option
set notimeout

" increase the timeoutlen (default: 1000)
set timeoutlen = 5000

Explanation: timeout & timeoutlen

By default (Idea)VIM will wait for timeoutlen milliseconds after each key press of any unfinished mapping sequence before it cancels the whole sequence and processes each key press individually one after another. To match this behavior the IDEA-Which-Key popup will only be visible till a mapping sequence is either completed or canceled. Without any adaptions the popup is only displayed for a brief moment and will not be very useful. Therefore you should definitively modify timout or timeoutlen according to your preferences.

IdeaVIM does not differentiate between timeout|timeoutlen and ttimeout|ttimeoutlen

Customization

You can customize several aspects of IDEA-Which-Key via variables in your .ideavimrc

Use the :source ~/.ideavimrc command to reload your config file

Descriptions

If no custom descriptions are defined, the right-hand side of all mappings will be displayed:

To provide custom names for prefixes and commands we need to configure one variable for every mapping:

let g:WhichKeyDesc_windows        = "<Space>w  +Windows"
let g:WhichKeyDesc_windows_delete = "<Space>wd delete-window"
let g:WhichKeyDesc_windows_split  = "<Space>ws split-window-below"
...

The <leader> key is also supported

let g:WhichKeyDesc_buffer        = "<leader>b  +Buffer"

Every variable's name has to start with g:WhichKeyDesc_ in order to be recognized by the plugin. The rest of the variable name can be set to whatever fits best with you. For the value of each variable use the right-hand side of the mapping followed by at least one space or tab characters and finished with the description string you want to be displayed.

Or if you prefer it in regular expressions:

Part	Regex	Details
Name	g:WhichKeyDesc_[a-zA-Z0-9_]+	the only valid characters for variable names are a-zA-Z0-9_
Value	(.*?)[ \t]+(.*)	group one is the mapping, group two your description

If you are familiar with vim-which-key or the emacs package which-key this handling seems odd and very inconvenient, as it requires a lot of variable definitions and therefore a lot of repetition. Unfortunately this is the case because the IdeaVim plugin only supports the following four types of variables:

• single quoted string
• double quoted string
• decimal number
• reference to another variable

Due to this limitation and the lack of any more convenient data types (array, list, dictionary, etc.) there is currently no "nicer" way of handling custom descriptions.

As of writing the current versions are Intellij 2020.3 and IdeaVim 0.64

VIM Actions

By default Idea-Which-Key will only display key mappings which are defined in the .ideavimrc file. If you wish it can also display default VIM actions like gg, zz, zt, <C-w>k, etc. in the popup. For this you need to set the following variable within your .ideavimrc:

let g:WhichKey_ShowVimActions = "true"

If you wish you can also add custom descriptions for VIM Actions the same way as for other key mappings:

let g:WhichKeyDesc_goto_top = "gg   goto first line"

Typed Keys

At the bottom of the popup you can see the keys you have typed so far as well as the current prefix description

You can hide this by adding the following to your .ideavimrc:

let g:WhichKey_ShowTypedSequence = "false"

Appearance

You can configure the appearance of certain UI elements by setting the following options:

Variable	Description	Values	Default Value
g:WhichKey_Divider	String to separate key and description	any string	→
g:WhichKey_FontFamily	Font to use for the popup	CSS font-family (see examples)	monospace
g:WhichKey_FontSize	Font size for the popup	Font size in point (for example 15, 22, etc.)	IDE default³
g:WhichKey_KeyStyle	Font style for the keys	bold, italic, none	bold
g:WhichKey_KeyColor	Font color for the keys	hex code or color keyword (default¹, keyword², "red", "blue", etc.)	default
g:WhichKey_PrefixStyle	Font style for the prefixes	bold, italic, none	none
g:WhichKey_PrefixColor	Font color for the prefixes	hex code or color keyword (default¹, keyword², "red", "blue", etc.)	keyword
g:WhichKey_CommandStyle	Font style for the commands	bold, italic, none	none
g:WhichKey_CommandColor	Font color for the commands	hex code or color keyword (default¹, keyword², "red", "blue", etc.)	default

¹default: the default foreground color of the currently used theme
²keyword: the color for "keywords" of the currently used theme
³Uses the IDE default value for the font size (without any configuration this should be 15)

Known issues

Should you check your idea.log file you will stumble across the following error:

ERROR - nSystem.impl.ActionManagerImpl - action with the ID "VimShortcutKeyAction" was already registered. Action being registered is  (null); Registered action is Shortcuts () Plugin: IDEA Which-Key [Plugin: eu.theblob42.idea.whichkey] 
com.intellij.diagnostic.PluginException: action with the ID "VimShortcutKeyAction" was already registered. Action being registered is  (null); Registered action is Shortcuts () Plugin: IDEA Which-Key [Plugin: eu.theblob42.idea.whichkey]

This is a known issue which will not compromise your usage of Intellij, IdeaVIM or IDEA-Which-Key in any way!

In order for IDEA-Which-Key to work the plugin needs to intercept every key stroke and check if there are any key mappings which should be displayed. In order to intercept any modified key stroke (Ctrl + w, Alt + n, etc.) or special keys without a corresponding character (Escape, Enter, etc.) the plugin overwrites the VimShortcutKeyAction of IdeaVIM which usually handles these (this is the reason for the shown error). After checking for anything to display the event is passed to the original class. Therefore no functionality is lost by using the IDEA-Which-Key plugin.