collapsing browser - Printable Version

-- b = browser name, included to make it easier

-- to plug this function into other scripts.

function toggle(b)

local count,state,one,two=1

-- selected line and its label

local me,label=b:value(),b:text(b:value())

if string.find(label,"%+%s*") then

  state,one,two="expanded","%+  ","%-  "

else

  state,one,two="collapsed","%-  ","%+  "

end

b:text(me,string.gsub(label,one,two)) -- swap + and -

-- optional output; cut off sep and the following + or - 

o:value("You "..state.." the "..string.gsub(label,sep..".%s*",""))

-- toggle all lines until reaching the next section or the browser end

while b:text(me+count) and not string.match(b:text(me+count),sep) do

  if state=="collapsed" then b:hide(me+count)

  else b:show(me+count)

  end

  count=count+1

end

end



ww=500; wh=200; f=10 -- window width, height, border

w=fltk:Fl_Window(ww,wh,"collapsible browser")

list=fltk:Fl_Hold_Browser(f,f,ww/2-f*2,wh-f*2)

list:selection_color(8)

h=fltk:Fl_Box(ww/2+f,f,ww/2-f*2,wh/2-f*2) -- help

h:align(149) -- align text inside top left

h:label([[Click the titles or press "Enter" to expand or collapse a section.



Press Alt+number to jump to the corresponding section.]])



function smove(me)

  local n=string.sub(me:label(),2) -- strip off "&"

  list:value(cat[tonumber(n)]) -- select the separator with index n

  local label=list:text(list:value()) -- get the text of selected line

  o:value("You jumped to the "..string.gsub(label,sep..".%s*",""))

  list:take_focus()

end

sbox=fltk:Fl_Box(ww/2+f,wh-f*8,f*3,f*2,"Move to section:")

sbox:align(20) -- inside left

-- buttons used to select section headers

s1=fltk:Fl_Button(ww-f*10,wh-f*8,f*3,f*2,"&1"); s1:callback(smove)

s2=fltk:Fl_Button(ww-f*7,wh-f*8,f*3,f*2,"&2"); s2:callback(smove)

s3=fltk:Fl_Button(ww-f*4,wh-f*8,f*3,f*2,"&3"); s3:callback(smove)

o=fltk:Fl_Output(ww/2+f,wh-f*4,ww/2-f*2,f*3) -- output



-- separator/subsection, prefix for the separator labels

-- format: bold text, gray background, underlined

sep="@b@B50@u"

t="    item:  " -- indentation



-- table to store the index of each separator

cat={}



-- contents of sections: label, item1, item2, ...

categories={

{sep.."-  first section","one-A","one-B","one-C"},

{sep.."-  second section","two A","to be","two C","two D"},

{sep.."-  third section","three-A","three-B","three-C","3-D","three-E","three-F"}

}



for k,v in ipairs(categories) do -- do each sub-table

  for i,s in ipairs(v) do

    if string.find(s,sep) then list:add(s); cat[k]=list:size() -- find the index of the separator

    else list:add(t..s) end -- add the string to the browser with optional indentation

  end

end

-- to start all collapsed, using the cat table to select the right lines

for k in ipairs(cat) do list:value(cat[k]); toggle(list) end

-- to start a specific section collapsed

--list:value(cat[3]); toggle(list)

list:value(1)

o:value("squishy browser demo")





list:callback( function()

if list:value()>0 then -- clicking a blank space can be fatal without this check

if Fl:event() == fltk.FL_RELEASE or Fl:event_key()==fltk.FL_Enter then -- on click or Enter

  if string.find(list:text(list:value()),sep) then toggle(list) -- if it's a separator

  else o:value([[You poked "]]..string.gsub(list:text(list:value()),t,"")..[["]]) -- print label to output, remove the indent

  end

end

end

end)

-- offscreen button that allows the list to respond to Enter key

enter=fltk:Fl_Return_Button(ww,wh,10,10)

enter:callback(function() list:do_callback() end)



w:show()

Fl:run()