iphone - Which method to use to display text ?Why? -


when drawing using coregraphics draw string/label have 2 methods

- (cgsize)drawinrect:(cgrect)rect withfont:(uifont *)font linebreakmode:(nslinebreakmode)linebreakmode alignment:(nstextalignment)alignment;

eg:

   [value drawinrect:cgrectmake(xvalue, rect.origin.y, objlegends.value *singleunitwidth,heightofbar)                  withfont:[uifont systemfontofsize:10.0f]             linebreakmode:nslinebreakbyclipping                 alignment:nstextalignmentcenter];

and

cg_extern void cgcontextshowtext(cgcontextref c, const char *string,     size_t length) cg_available_starting(__mac_10_0, __iphone_2_0);

eg

        cgcontextsavegstate(context);         // tanslate , scale upside-down compensate quartz's inverted coordinate system         cgcontextsettextmatrix(context, cgaffinetransformmake(1.0,0.0, 0.0, -1.0, 0.0, 0.0));          cgcontextselectfont(context, "helvetica", 10.0f, kcgencodingmacroman);         cgcontextsettextdrawingmode(context, kcgtextfill);         cgcontextsettextposition(context, xvalue, rect.size.height-heightoftext);           if ([value canbeconvertedtoencoding:nsmacosromanstringencoding])         {             cgcontextshowtext(context, [value cstringusingencoding:nsmacosromanstringencoding],5);             //                              strlen([value cstringusingencoding:nsmacosromanstringencoding]));         }         cgcontextrestoregstate(context);

which 1 method , why?

the best method 1 simplest achieve goal. higher level of api can use better. if can use nsstring method should - unless can use uilabel (or similar) job you. try write least code possible , reuse code that's provided you, dropping use lower level api if requirements or performance profiling show need to.


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