UITableView's NSString memory leak on iphone when encoding with NSUTF8StringEncoding
- by vince
my UITableView have serious memory leak problem only when the NSString is NOT encoding with NSASCIIStringEncoding.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = @"cell";
UILabel *textLabel1;
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
textLabel1 = [[UILabel alloc] initWithFrame:CGRectMake(105, 6, 192, 22)];
textLabel1.tag = 1;
textLabel1.textColor = [UIColor whiteColor];
textLabel1.backgroundColor = [UIColor blackColor];
textLabel1.numberOfLines = 1;
textLabel1.adjustsFontSizeToFitWidth = NO;
[textLabel1 setFont:[UIFont boldSystemFontOfSize:19]];
[cell.contentView addSubview:textLabel1];
[textLabel1 release];
} else {
textLabel1 = (UILabel *)[cell.contentView viewWithTag:1];
}
NSDictionary *tmpDict = [listOfInfo objectForKey:[NSString stringWithFormat:@"%@",indexPath.row]];
textLabel1.text = [tmpDict objectForKey:@"name"];
return cell;
}
-(void) readDatabase {
NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDir = [documentPaths objectAtIndex:0];
databasePath = [documentsDir stringByAppendingPathComponent:[NSString stringWithFormat:@"%@",myDB]];
sqlite3 *database;
if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) {
const char sqlStatement = [[NSString stringWithFormat:@"select id,name from %@ order by orderid",myTable] UTF8String];
sqlite3_stmt *compiledStatement;
if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) {
while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
NSString *tmpid = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 0)];
NSString *tmpname = [NSString stringWithCString:(const char *)sqlite3_column_text(compiledStatement, 1) encoding:NSUTF8StringEncoding];
[listOfInfo setObject:[[NSMutableDictionary alloc] init] forKey:tmpid];
[[listOfInfo objectForKey:tmpid] setObject:[NSString stringWithFormat:@"%@", tmpname] forKey:@"name"];
}
}
sqlite3_finalize(compiledStatement);
debugNSLog(@"sqlite closing");
}
sqlite3_close(database);
}
when i change the line
NSString *tmpname = [NSString stringWithCString:(const char *)sqlite3_column_text(compiledStatement, 1) encoding:NSUTF8StringEncoding];
to
NSString *tmpname = [NSString stringWithCString:(const char *)sqlite3_column_text(compiledStatement, 1) encoding:NSASCIIStringEncoding];
the memory leak is gone
i tried NSString stringWithUTF8String and it still leak.
i've also tried:
NSData *dtmpname = [NSData dataWithBytes:sqlite3_column_blob(compiledStatement, 1) length:sqlite3_column_bytes(compiledStatement, 1)];
NSString *tmpname = [[[NSString alloc] initWithData:dtmpname encoding:NSUTF8StringEncoding] autorelease];
and the problem remains, the leak occur when u start scrolling the tableview.
i've actually tried other encoding and it seems that only NSASCIIStringEncoding works(no memory leak)
any idea how to get rid of this problem?