iphone - Storing/Extracting Objects to/from NSDictionary -

i getting errors using nsdictionary when trying assign it's contents new variables/objects. maybe isn't posible? thought be. i'm not sure if can use non-objective c specific objects in dictionary. can you?

nsdictionary *preprocessresult = [[nsdictionary alloc] initwithdictionary: [self preprocessing:testimage]]; iplimage* resultimage = [preprocessresult objectforkey:@"resultimage"]; int numchars = [preprocessresult objectforkey:@"numberchars"]; [preprocessresult release]; 

and here method calling create dictionary:

- (nsdictionary*) preprocessing: (iplimage*) testimage {  //do stuff image  nsdictionary *testimage_andnumchars = [nsdictionary dictionarywithobjectsandkeys:resultimage,  @"resultimage", numchars, @"numberchars", nil];  return testimage_andnumchars; } 

is not correct way handle this? error when create dictionary is:

"cannot convert 'iplimage*' 'objc_object*' in argument passing"

and when retrieve dictionary elements get:

"cannot convert 'objc_object*' 'iplimage*' in initialization" , "invalid conversion 'objc_object*' 'int' ".

i've read apple docs on nsdictionary got me far, not sure go here.

thanks in advance.

putting shortly, nsdictionary values must nsobjects.

you should store int nsnumber using e.g.:

[nsnumber numberwithint:numchars] 

when retrieving value can use e.g.:

int numchars = [[preprocessresult objectforkey:@"numberchars"] intvalue];