selected entry callback

[xzbdmw]

for lsp_document_symbols, I want to auto jump to location and highlight code ranges as I through fzf result list rather than look at preview windows, could you give me some hint where the callback get executed in source code?

[ibhagwan]

LSP symbols uses the same previewer as any file entry previewer, it displays file, line and column.

If you want to do something different look the advanced Wiki, create your own previewer and do whatever you want with the callback:
https://github.com/ibhagwan/fzf-lua/wiki/Advanced#preview-nvim-builtin

[xzbdmw]

Hmm, how could I get range information in previewer functions

[ibhagwan]

Unfortunately the builtin previewer isn’t well documented but fortunately lua is very simple, clone the code and explore, it’s fairly simple.

[xzbdmw]

Yes, I'm trying to find the place where preview(each time I change selection) is called, so I can inject some code there, but the callback is hard to track down

[xzbdmw]

As I add some print, range information is not passed to preview functions, so I have to somehow write some glue code.

[ibhagwan]

You’re correct, for what you want to achieve you’ll have to save metadata somewhere, it’s not overly complex but we’re still dealing with an external terminal process (fzf) which has awareness about the selected lines only.

[ibhagwan]

Builtin preview entry point:

fzf-lua/lua/fzf-lua/previewer/builtin.lua

Lines 288 to 294 in 743647f

	function Previewer.base:cmdline(_)
	local act = shell.raw_action(function(items, _, _)
	self:display_entry(items[1])
	return ""
	end, "{}", self.opts.debug)
	return act
	end

[xzbdmw]

Succeed! final question, how to trigger preview function if I don't want to show preview?

[ibhagwan]

Take a look at how the live color scheme preview works with colorschemes, the fzf previewer is set to nohidden:0% (otherwise the callback isn’t triggered), and the preview action is set to:

fzf-lua/lua/fzf-lua/providers/colorschemes.lua

Lines 50 to 66 in 743647f

	if opts.live_preview then
	-- must add ':nohidden' or fzf ignores the preview action
	opts.fzf_opts["--preview-window"] = "nohidden:right:0"
	opts.preview = shell.raw_action(function(sel)
	if opts.live_preview and sel then
	vim.cmd("colorscheme " .. sel[1])
	if type(opts.cb_preview) == "function" then
	opts.cb_preview(sel, opts)
	end
	end
	end, nil, opts.debug)
	end
	opts.fn_selected = function(selected, o)
	-- reset color scheme if live_preview is enabled
	-- and nothing or non-default action was selected
	if opts.live_preview and (not selected or #selected[1] > 0) then