koreader/frontend/ui/widget/container/inputcontainer.lua

local WidgetContainer = require("ui/widget/container/widgetcontainer")
local Event = require("ui/event")
local Geom = require("ui/geometry")
local DEBUG = require("dbg")

--[[
an InputContainer is an WidgetContainer that handles input events

an example for a key_event is this:

    PanBy20 = {
        { "Shift", Input.group.Cursor },
        seqtext = "Shift+Cursor",
        doc = "pan by 20px",
        event = "Pan", args = 20, is_inactive = true,
    },
    PanNormal = {
        { Input.group.Cursor },
        seqtext = "Cursor",
        doc = "pan by 10 px", event = "Pan", args = 10,
    },
    Quit = { {"Home"} },

it is suggested to reference configurable sequences from another table
and store that table as configuration setting
--]]
local InputContainer = WidgetContainer:new{
    vertical_align = "top",
}

function InputContainer:_init()
    -- we need to do deep copy here
    local new_key_events = {}
    if self.key_events then
        for k,v in pairs(self.key_events) do
            new_key_events[k] = v
        end
    end
    self.key_events = new_key_events

    local new_ges_events = {}
    if self.ges_events then
        for k,v in pairs(self.ges_events) do
            new_ges_events[k] = v
        end
    end
    self.ges_events = new_ges_events

    if not self.dimen then
        self.dimen = Geom:new{}
    end
end

function InputContainer:paintTo(bb, x, y)
    self.dimen.x = x
    self.dimen.y = y
    if self[1] then
        if self.vertical_align == "center" then
            local content_size = self[1]:getSize()
            self[1]:paintTo(bb, x, y + math.floor((self.dimen.h - content_size.h)/2))
        else
            self[1]:paintTo(bb, x, y)
        end
    end
end

--[[
the following handler handles keypresses and checks if they lead to a command.
if this is the case, we retransmit another event within ourselves
--]]
function InputContainer:onKeyPress(key)
    for name, seq in pairs(self.key_events) do
        if not seq.is_inactive then
            for _, oneseq in ipairs(seq) do
                if key:match(oneseq) then
                    local eventname = seq.event or name
                    return self:handleEvent(Event:new(eventname, seq.args, key))
                end
            end
        end
    end
end

function InputContainer:onGesture(ev)
    for name, gsseq in pairs(self.ges_events) do
        for _, gs_range in ipairs(gsseq) do
            --DEBUG("gs_range", gs_range)
            if gs_range:match(ev) then
                local eventname = gsseq.event or name
                return self:handleEvent(Event:new(eventname, gsseq.args, ev))
            end
        end
    end
end

return InputContainer