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POProblem while scrolling Table View
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  1. POProblem while scrolling Table View
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    copied!<p>I have the following problem while i scroll the table view: </p> <pre><code>NSCFString objectAtIndex:]: unrecognized selector sent to instance </code></pre> <p>I create NSDictionary tableContents and when i scroll it becomes deallocated. This is my code: </p> <pre><code>- (void)viewDidLoad { lessonsInGroup1 = [NSMutableArray array]; lessonsInGroup2 = [NSMutableArray array]; lessonsInGroup1 = [self grabRowsInGroup:@"1"]; lessonsInGroup2 = [self grabRowsInGroup:@"2"]; NSDictionary *temp =[[NSDictionary alloc]initWithObjectsAndKeys:lessonsInGroup1,@"General Information",lessonsInGroup2,@"LaTeX Examples", nil]; //[[tableContents alloc] init]; self.tableContents =temp; [temp release]; NSLog(@"table %@",self.tableContents); NSLog(@"table with Keys %@",[self.tableContents allKeys]); self.sortedKeys =[[self.tableContents allKeys] sortedArrayUsingSelector:@selector(compare:)]; NSLog(@"sorted %@",self.sortedKeys); [lessonsInGroup1 release]; [lessonsInGroup2 release]; //[table reloadData]; // Uncomment the following line to display an Edit button in the navigation bar for this view controller. // self.navigationItem.rightBarButtonItem = self.editButtonItem; [super viewDidLoad]; </code></pre> <p>}</p> <pre><code>- (NSMutableArray *) grabRowsInGroup:(NSString*)GroupID{ NSMutableArray *groupOfLessons; groupOfLessons = [[NSMutableArray alloc] init]; char *sqlStatement; int returnCode; sqlite3_stmt *statement; NSString *databaseName; NSString *databasePath; // Setup some globals databaseName = @"TexDatabase.sql"; // Get the path to the documents directory and append the databaseName NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDir = [documentPaths objectAtIndex:0]; databasePath = [documentsDir stringByAppendingPathComponent:databaseName]; // Setup the database object sqlite3 *database; // Open the database from the users filessytem if(sqlite3_open([databasePath UTF8String], &amp;database) != SQLITE_OK) { fprintf(stderr, "Error in opening the database. Error: %s", sqlite3_errmsg(database)); sqlite3_close(database); return; } sqlStatement = sqlite3_mprintf( "SELECT * FROM Lessons WHERE LessonGroup = '%s';", [GroupID UTF8String]); returnCode = sqlite3_prepare_v2(database, sqlStatement, strlen(sqlStatement), &amp;statement, NULL); if(returnCode != SQLITE_OK) { fprintf(stderr, "Error in preparation of query. Error: %s", sqlite3_errmsg(database)); sqlite3_close(database); return; } returnCode = sqlite3_step(statement); while(returnCode == SQLITE_ROW) { NSString *aLessonID = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 0)]; NSString *aLessonGroup = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 1)]; NSString *aLessonTopic = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 2)]; NSString *aLessonText = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 3)]; NSString *aLessonCode = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 4)]; NSString *aLessonPicture = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 5)]; /*NSLog(aLessonID); NSLog(aLessonGroup); NSLog(aLessonTopic); NSLog(aLessonText); NSLog(aLessonCode); NSLog(aLessonPicture);*/ // Create a new busCit object with the data from the database Lesson *lesson = [[Lesson alloc] initWithLessonID:aLessonID LessonGroup:aLessonGroup LessonTopic:aLessonTopic LessonText:aLessonText LessonCode:aLessonCode LessonPicture:aLessonPicture]; [groupOfLessons addObject:lesson]; returnCode = sqlite3_step(statement); } sqlite3_finalize(statement); sqlite3_free(sqlStatement); return [groupOfLessons autorelease]; </code></pre> <p>}</p>
 

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