builtin/fstk/ui.lua

   1 --Minetest
   2 --Copyright (C) 2014 sapier
   3 --
   4 --self program is free software; you can redistribute it and/or modify
   5 --it under the terms of the GNU Lesser General Public License as published by
   6 --the Free Software Foundation; either version 2.1 of the License, or
   7 --(at your option) any later version.
   8 --
   9 --self program is distributed in the hope that it will be useful,
  10 --but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 --MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 --GNU Lesser General Public License for more details.
  13 --
  14 --You should have received a copy of the GNU Lesser General Public License along
  15 --with self program; if not, write to the Free Software Foundation, Inc.,
  16 --51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17
  18 ui = {}
  19 ui.childlist = {}
  20 ui.default = nil
  21
  22 --------------------------------------------------------------------------------
  23 function ui.add(child)
  24         --TODO check child
  25         ui.childlist[child.name] = child
  26
  27         return child.name
  28 end
  29
  30 --------------------------------------------------------------------------------
  31 function ui.delete(child)
  32
  33         if ui.childlist[child.name] == nil then
  34                 return false
  35         end
  36
  37         ui.childlist[child.name] = nil
  38         return true
  39 end
  40
  41 --------------------------------------------------------------------------------
  42 function ui.set_default(name)
  43         ui.default = name
  44 end
  45
  46 --------------------------------------------------------------------------------
  47 function ui.find_by_name(name)
  48         return ui.childlist[name]
  49 end
  50
  51 --------------------------------------------------------------------------------
  52 --------------------------------------------------------------------------------
  53 -- Internal functions not to be called from user
  54 --------------------------------------------------------------------------------
  55 --------------------------------------------------------------------------------
  56
  57 --------------------------------------------------------------------------------
  58 function ui.update()
  59         local formspec = ""
  60
  61         -- handle errors
  62         if gamedata ~= nil and gamedata.errormessage ~= nil then
  63                 local ar = gamedata.errormessage:split("\n")
  64                 for i = 1, #ar do
  65                         local text = ar[i]
  66                         -- Hack to add word wrapping.
  67                         -- TODO: Add engine support for wrapping in formspecs
  68                         while #text > 80 do
  69                                 if formspec ~= "" then
  70                                         formspec = formspec .. ","
  71                                 end
  72                                 formspec = formspec .. core.formspec_escape(string.sub(text, 1, 79))
  73                                 text = string.sub(text, 80, #text)
  74                         end
  75                         if formspec ~= "" then
  76                                 formspec = formspec .. ","
  77                         end
  78                         formspec = formspec .. core.formspec_escape(text)
  79                 end
  80                 local error_title
  81                 if string.find(gamedata.errormessage, "ModError") then
  82                         error_title = fgettext("An error occured in a Lua script, such as a mod:")
  83                 else
  84                         error_title = fgettext("An error occured:")
  85                 end
  86                 formspec = "size[12,5]" ..
  87                                 "label[0.5,0;" .. error_title ..
  88                                 "]textlist[0.2,0.8;11.5,3.5;;" .. formspec ..
  89                                 "]button[4.5,4.6;3,0.5;btn_error_confirm;" .. fgettext("Ok") .. "]"
  90         else
  91                 local active_toplevel_ui_elements = 0
  92                 for key,value in pairs(ui.childlist) do
  93                         if (value.type == "toplevel") then
  94                                 local retval = value:get_formspec()
  95
  96                                 if retval ~= nil and retval ~= "" then
  97                                         active_toplevel_ui_elements = active_toplevel_ui_elements +1
  98                                         formspec = formspec .. retval
  99                                 end
 100                         end
 101                 end
 102
 103                 -- no need to show addons if there ain't a toplevel element
 104                 if (active_toplevel_ui_elements > 0) then
 105                         for key,value in pairs(ui.childlist) do
 106                                 if (value.type == "addon") then
 107                                         local retval = value:get_formspec()
 108
 109                                         if retval ~= nil and retval ~= "" then
 110                                                 formspec = formspec .. retval
 111                                         end
 112                                 end
 113                         end
 114                 end
 115
 116                 if (active_toplevel_ui_elements > 1) then
 117                         print("WARNING: ui manager detected more then one active ui element, self most likely isn't intended")
 118                 end
 119
 120                 if (active_toplevel_ui_elements == 0) then
 121                         print("WARNING: not a single toplevel ui element active switching to default")
 122                         ui.childlist[ui.default]:show()
 123                         formspec = ui.childlist[ui.default]:get_formspec()
 124                 end
 125         end
 126         core.update_formspec(formspec)
 127 end
 128
 129 --------------------------------------------------------------------------------
 130 function ui.handle_buttons(fields)
 131
 132         if fields["btn_error_confirm"] then
 133                 gamedata.errormessage = nil
 134                 update_menu()
 135                 return
 136         end
 137
 138         for key,value in pairs(ui.childlist) do
 139
 140                 local retval = value:handle_buttons(fields)
 141
 142                 if retval then
 143                         ui.update()
 144                         return
 145                 end
 146         end
 147 end
 148
 149
 150 --------------------------------------------------------------------------------
 151 function ui.handle_events(event)
 152
 153         for key,value in pairs(ui.childlist) do
 154
 155                 if value.handle_events ~= nil then
 156                         local retval = value:handle_events(event)
 157
 158                         if retval then
 159                                 return retval
 160                         end
 161                 end
 162         end
 163 end
 164
 165 --------------------------------------------------------------------------------
 166 --------------------------------------------------------------------------------
 167 -- initialize callbacks
 168 --------------------------------------------------------------------------------
 169 --------------------------------------------------------------------------------
 170 core.button_handler = function(fields)
 171         if fields["btn_error_confirm"] then
 172                 gamedata.errormessage = nil
 173                 ui.update()
 174                 return
 175         end
 176
 177         if ui.handle_buttons(fields) then
 178                 ui.update()
 179         end
 180 end
 181
 182 --------------------------------------------------------------------------------
 183 core.event_handler = function(event)
 184         if ui.handle_events(event) then
 185                 ui.update()
 186                 return
 187         end
 188
 189         if event == "Refresh" then
 190                 ui.update()
 191                 return
 192         end
 193 end