ios - Global NSString without alloc access only in 2 place or in two method and in 3rd place it crash the application -

here nsstring *documentspath declare in globally.

#import "detailviewcontroller.h" #import "information.h" @interface detailviewcontroller () {     nsstring *documentspath;     nsarray *paths;  } 

assigning , accessing in viewdidload method.

- (void)viewdidload {     nslog(@"enter viewdidload detailviewcontroller");     paths = nssearchpathfordirectoriesindomains (nsdocumentdirectory, nsuserdomainmask, yes);     **documentspath** = [paths objectatindex:0];     nsstring *plistpath = [**documentspath**  stringbyappendingpathcomponent:@"infodetail.plist"]; } 

also accessing in settingcellimage method

-(void)settingcellimage:(uitableviewcell *)cell noofrow:(int)row {     nslog(@"enter in settingcellimage method");     nslog(@"doc path cell ===>%@",documentspath);      nsstring *imagepath = [**documentspath** stringbyappendingformat:[nsstring  stringwithformat:@"/%d.png",row]];   } 

but when use in didselectrowatindexpath method crash application.

(void)tableview:(uitableview *)tableview didselectrowatindexpath:(nsindexpath *)indexpath {      information *information = [[[information alloc]initwithnibname:@"information" bundle:nil]autorelease];      information.infodict = [test objectatindex:indexpath.row];      nslog(@"selected row no ==> %d",indexpath.row);       nslog(@"using @=== %d",indexpath.row);      nslog(@"documents path == %@",**documentspath**);// here gives exe_bad_access.      nsstring *selectedimagepath = [documentspath stringbyappendingformat:[nsstring stringwithformat:@"/%d.png",indexpath.row+1]];    } 

i'm new in iphone development , demo project. please me possible. , please give me answer in easy way can understand fast. , yes know i'm not alloc init documentspath direct assign in viewdidload method, , want know why access in 2 places , in 3rd place crash application. hope can me. thank you!

since you're not using arc, have make sure retain/releasing/autoreleasing objects. what's happening documentspath got released , accessing released object. assign string so:

documentspath = [[nsstring stringwithstring:[paths objectatindex:0]] retain]; 

and have release in dealloc call.