ios - NSMutableArray not being modified properly when manipulated in other class -

i have nsmutablearray property in view controller class, , line being used in 2 other classes. 1 of classes manipulates array (adds more objects it) , reads it. when 1 of classes manipulates array, not being modified in view controller class, instantiated in. therefore, third class not getting proper date needs.

in view controller class:

@property (nonatomic, strong) nsmutablearray *entitylines; 

in other 2 classes:

@property (nonatomic, weak) nsmutablearray *linestodraw; @property (nonatomic, weak) nsmutablearray *linesforkey; 

array initialization:

- (id)init {     self = [super init];     if (self) {         self.title = @"line graph";         linequery = [[linegraphquery alloc] init];         entitylines = [nsmutablearray array];     }      return self; } 

modifying array:

     - (void)drawrect:(cgrect)rect {     if(data.namedentitydata.count > 0) {         cgcontextref context = uigraphicsgetcurrentcontext();         cgcontextsetlinewidth(context, line_width);         cgcontextsetlinecap(context, kcglinecapround);         cgcontextsetfillcolorwithcolor(context, [[uicolor blackcolor] cgcolor]);         cgcontextfillrect(context, rect);          [self clearalllines];         for(nsstring *key in [data.namedentitydata allkeys]) {             entityline *entityline = [self getnamedentitylineforname:key];             if(!entityline) {                 entityline = [[entityline alloc] init];                 entityline.name = key;                 entityline.color = [self getrandomcolor];             }             float intervalx = starting_interval_x;             float lastrangey = min_event_count_y;              cgcontextsetstrokecolorwithcolor(context, [entityline.color cgcolor]);             nsarray *events = [data.namedentitydata objectforkey:key];             nsinteger rangedifference = data.endyear - data.beginyear;              for(int = 0; < numberofdaterangeintervals; i++) {                 int startyearrange = data.beginyear + (i * (rangedifference / numberofdaterangeintervals));                 int endyearrange = (i == numberofdaterangeintervals - 1) ? data.endyear : data.beginyear + ((i + 1) * (rangedifference / numberofdaterangeintervals) - 1);                 int eventcount = [self getcountforevents:events withbeginyear:startyearrange andendyear:endyearrange];                  line *line = [[line alloc] init];                 line.begin = cgpointmake(intervalx, lastrangey);                 cgcontextmovetopoint(context, line.begin.x, line.begin.y);                 intervalx += intervalxincrement;                 lastrangey = [self getycoordinateforeventcount:eventcount];                 line.end = cgpointmake(intervalx, lastrangey);                 [entityline addline:line];                  cgcontextaddlinetopoint(context, line.end.x, line.end.y);                 cgcontextstrokepath(context);             }             [linestodraw addobject:entityline];         }          [self draweventcountlabelswithcontext:context];         [self drawdaterangelabelswithcontext:context];     } }  - (void)clearalllines {     for(entityline *line in linestodraw)         [line clearlines]; } 

other class setting reference nsmutablearray:

linegraph.linestodraw = self.entitylines; linekey.linesforkey = self.entitylines; 

giving properties (or instance variables) same name in different classes not cause them point same objects. after creating array, need pass pointer array property in other class instances.

@interface abcfirstclass ()  @property (nonatomic, strong) nsmutablearray *lines; @property (nonatomic, strong) abcanotherclass *otherclass;  // has property named "lines".  @end   @implementation abcfirstclass  - (id)init {     self = [super init];     if (self) {         self.lines = [nsmutablearray arraywithobjects:@"1", @"2", @"3", nil];         self.otherclass = [[abcanotherclass alloc] init];         self.otherclass.lines = self.lines;           // both classes have pointer same array object.     }     return self; } 

this doesn't need happen in -init method. maybe totally different class gets pointer 1 , passes other.

note i'd work ivars directly in -init (_lines, _otherclass), wanted keep example simple.