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Corona
TMwww.anscamobile.com TMwww.anscamobile.comWhat’s CoronaA simple, yet powerful framework allowing rapid mobile cross platform application development. TMwww.anscamobile.comCorona 102 Functions & EventListeners TMwww.anscamobile.comCorona framework based on Lua TMwww.anscamobile.comCorona Lua resourceshttp://ww.lua.orghttp://www.lua.org/lua-l.htmlhttp://developer.anscamobile.com/http://en.wikipedia.org/wiki/Lua_ TMwww.anscamobile.comCorona Without functionslocal text = display.newText("hello",100,200,"Helvetica",24);textObj:setTextColor(r,g,b);Disadvantages:When program begins to get too big, difficult to manage codereusing code becomes hard to break apartdebugging becomes a nightmareno sense of where program starts TMwww.anscamobile.comCorona With Functions:local function STextColor(textObj, r,g,b) textObj:setTextColor(r,g,b);endlocal function main()local text = display.newText("hello",100,200,"Helvetica",24);STxtColor(text,255,0,0);endmain()Advantages:easier to manage codeeasier to re-use code on other programs as welleasier to debug since you can narrow down where error occursa sense of where program starts TMwww.anscamobile.comCorona Functions:•First-class values.•Passed by value.•Stored in tables.•Returned from functions.•Global and local.•called from other ‘packages’ TMwww.anscamobile.comCorona Function Definitions:function name(args) body return [values]endGlobal Functionlocal function name(args) body return [values]endfunction local to file scopef = function (args) body return [values]endAnonymous functionfunction ( . ) bodyreturn values] end( .) indicates variable args and { .} places them in a table where they processed in standard way. TMwww.anscamobile.comCorona More function definitions:function obj:name(args) body return [values]endObject function getting extra args and self