I have an NSObject that I am using to store/hold properties of an object, one of them being a "Name" property cast as an NSString. I am also pulling data from a SQLite DB for said object using the following:
- (void) getDataToDisplay:(NSString *)dbPath {
if (sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK) {
NSString *queryOnStyle = [NSString stringWithFormat:
#"SELECT WineId, Name FROM wine WHERE StyleId = %d", dataManager.styleId];
const char *sql = [queryOnStyle UTF8String];
sqlite3_stmt *selectstmt;
if(sqlite3_prepare_v2(database, sql, -1, &selectstmt, NULL) == SQLITE_OK) {
while(sqlite3_step(selectstmt) == SQLITE_ROW) {
Wine *w = [[Wine alloc] init];
w.wineId = sqlite3_column_int(selectstmt, 0);
w.wineName = [NSString stringWithUTF8String:
(char *)sqlite3_column_text(selectstmt, 1)];
[dataManager.wines addObject:w];
[w release];
}
}
}
else
sqlite3_close(database); //Even though the open call failed, close the database connection to release all the memory.
}
Wine being my object. If I were to log w.wineName at this point, there is no problem. The problem occurs later when I try to access the properties of the object from within the array, dataManager.wines, in a custom tableView. It suddenly treats my wineName as a UIImageView rather than an NSString...
I for the life of me cannot trace anything back to ever being cast as a UIImageView and have no idea why it would be setting just that property as such. Here is the code for my custom tableView:
#pragma mark -
#pragma mark HorizontalTableViewDelegate methods
- (NSInteger)numberOfColumnsForTableView:(HorizontalTableView *)tableView {
return [dataManager.wines count];
}
- (UIView *)tableView:(HorizontalTableView *)aTableView viewForIndex:(NSInteger)index {
UIView *vw = [aTableView dequeueColumnView];
if (!vw) {
[[NSBundle mainBundle] loadNibNamed:#"ColumnView" owner:self options:nil];
vw = self.columnView;
self.columnView = nil;
}
// Get the wineId from the array of wineId integers
Wine *w = [dataManager.wines objectAtIndex:index];
int tempWineId = w.wineId;
NSString *tempWineName = [NSString stringWithFormat:#"%#", w.wineName];
NSLog(#"%#", tempWineName); \\RETURNS TEMPWINENAME AS A UIIMAGEVIEW
[w release];
return vw;
}
- (CGFloat)columnWidthForTableView:(HorizontalTableView *)tableView {
//TODO: This value needs to change if changed in IB
return 209.0f;
}
any ideas?
Resolved in comments of question by RichB:
is w.wineName a retain'ed property ? This sounds a bit like the string is being auto released. Could you post the definition of the Wine object?
Related
I have a database manager which successfully loads a string from my sqlite database, and then uses it to create an object. I add multiple of these objects to an array and return it to which ever class I'm calling it from.
I have no problem using the returned array in the method I call it from, but when other methods in the class try to access it, the string element is out of scope.
Here is my relavent code.
In DBManager.m:
-(NSArray *)loadObjectData {
NSMutableArray *myArray = [[NSMutableArray alloc] init];
//prepare query and statement
NSString *query = [NSString stringWithFormat:#"SELECT * FROM object;"];
sqlite3_stmt *statement;
//perform query
if (sqlite3_prepare_v2(database, [query UTF8String], -1, &statement, nil) != SQLITE_OK)
NSLog(#"Prepare Error. '%s'", sqlite3_errmsg(database));
//get data
while (sqlite3_step(statement) == SQLITE_ROW) {
//read values
int anInt = sqlite3_column_int(statement, 0);
NSString *aString = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 1)];
//add new object to list
[myArray addObject:[[Object alloc] initWithID:anInt Name:aString]];
}
if(sqlite3_finalize(statement) != SQLITE_OK)
NSLog(#"Finalize statement error.");
return [myArray autorelease];
}
In XViewController.h:
NSArray *listData;
SessionData *sessionData;
#property (nonatomic, retain) NSArray *listData;
#property (nonatomic, retain) SessionData *sessionData;
In XViewController.m:
- (void)viewDidLoad
{
dbMan = [DBManager sharedDBMananager]; //its a singleton
//Load objects to display in table
self.listData = [dbMan loadObjectData];
//if i try to use listData here, it works fine.
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
//normal stuff cut out
// Configure the cell...
//the following line fails because the string in the object out of scope
cell.textLabel.text = [[listData objectAtIndex:[indexPath row]] aString];
//trying to access [[listData objectAtIndex:[indexPath row]] anInt] works fine though.
return cell;
}
If I replace the line (in my loadObjectData method):
NSString *aString = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 2)];
with this:
NSString *aString = #"String";
everything works fine.
Take a look at this question's accepted answer - What does assigning a literal string to an NSString with "=" actually do?
The string literal ( #"String" ) works because it is statically allocated and does not need to be retained/released. [NSString stringWithUTF8String:] creates an autoreleased string. If you are not retaining it in your initWithID:Name: method then it is being released which is why your code isn't working. In your initWithID:Name: method at a retain when you reassign the name to your object's instance variable.
In Object class have you retained this string if not then i think you should and release this string in dealloc
I have a massive problem with SQLite in my iPhone app, that needs to be fixed for a client soon! Basically i'm pulling a column from a database and loading it into a table view on viewWillAppear. It works fine, for the first few times the view is loaded but then suddenly it starts return empty (null) values. Upon inspection it appears that there is an issue with opening the database maybe but this is my first SQLite project so it's hard to figure out what's going on.
Here is the code I use to pull the SQL information:
+ (void) getInitialDataToDisplay:(NSString *)dbPath {
NSLog(#"INCOME CALLED 1");
NavTabAppDelegate *appDelegate = (NavTabAppDelegate *)[[UIApplication sharedApplication] delegate];
appDelegate.incomeArray = [[NSMutableArray alloc] init];
if (sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK) {
NSLog(#"INCOME CALLED 2");
const char *sql = "select IncomeID, IncomeName from Income ORDER BY IncomeName asc";
//const char *sql2 = "select categoryID, Size from coffee";
sqlite3_stmt *selectstmt;
if(sqlite3_prepare_v2(database, sql, -1, &selectstmt, NULL) == SQLITE_OK) {
NSLog(#"INCOME CALLED 3");
while(sqlite3_step(selectstmt) == SQLITE_ROW) {
NSLog(#"INCOME CALLED 4");
NSInteger primaryKey = sqlite3_column_int(selectstmt, 0);
Income *incomeObj = [[Income alloc] initWithPrimaryKey:primaryKey];
//This is how I pull info from the database using the above select statement and setting it in the coffeeObj property of Coffee class
incomeObj.incomeName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(selectstmt, 1)];
//coffeeObj.coffeeSize = [NSString stringWithUTF8String:(char *)sqlite3_column_text(selectstmt, 2)];
incomeObj.isDirty = NO;
[appDelegate.incomeArray addObject:incomeObj];
[incomeObj release];
NSLog(#"INCOME OBJECTS %#", incomeObj.incomeName);
//NSLog(#"CALLED");
}
}
}
else{
sqlite3_close(database); //Even though the open call failed, close the database connection to release all the memory
NSLog(#"INCOME CALLED 5");
}
NSLog(#"INCOME CALLED 6");
}
I am calling the code in viewWillAppear as follows:
[Income getInitialDataToDisplay:[appDelegate getDBPath]];
Also this is the output from my console when the error occurs:
2011-06-17 12:21:48.307 CashCal[318:707] GET DB PATH CALLED
2011-06-17 12:21:48.310 CashCal[318:707] /var/mobile/Applications/2BD7CA1D-C7AB-4425-B5C1-974C4F4D057C/Documents/SQL.sqlite
2011-06-17 12:21:48.312 CashCal[318:707] INCOME CALLED 1
2011-06-17 12:21:48.314 CashCal[318:707] INCOME CALLED 5
2011-06-17 12:21:48.318 CashCal[318:707] INCOME CALLED 6
It appears the problem is with the first if statement opening the database. I really need help on this one
You should always destroy prepared statements by calling sqlite3_finalize(your_stmt). And you should always close youre connection not only if it sqlite3_open() failed.
Also do something like this:
if(sqlite3_prepare_v2(database, sql, -1, &selectstmt, NULL) == SQLITE_OK) {
//your code here
} else {
//print error
NSLog(#"sql-error: %s", sqlite3_errmsg(database));
}
for clarification, here a interface for your db, that should avoid opening the db when its allready open, and makes code cleaner
DBi.h
#import <Foundation/Foundation.h>
#import <sqlite3.h>
#interface DBi : NSObject {
sqlite3* db;
}
- (void)opendDB;
- (void)closeDB;
- (NSArray*)getIcons;
#end
DBi.m
#import "DBi.h"
#import "Income.h"
static DBi *sharedDBi = nil;
#implementation DBi
- (void)dealloc {
sqlite3_close(db);
[super dealloc];
}
+ (DBi*)sharedManager {
if (sharedDBi == nil) {
sharedDBi = [[super allocWithZone:NULL] init];
[sharedDBi opendDB];
}
return sharedDBi;
}
+ (id)allocWithZone:(NSZone *)zone {
return [[self sharedManager] retain];
}
- (void)opendDB {
NSString *dbPath = [[NSBundle mainBundle]pathForResource:#"path_to_db_file"ofType:#"sqlite"];
//open the database
if(!sqlite3_open([dbPath UTF8String], &db) == SQLITE_OK) {
NSLog(#"connection to db failed");
sqlite3_close(db);
}
}
- (void)closeDB {
sqlite3_close(db);
}
- (NSArray*)getIncoms {
NSMutableArray rArray = [[[NSMutableArray alloc] init] autorelease];
const char *sql = "select IncomeID, IncomeName from Income ORDER BY IncomeName asc";
//const char *sql2 = "select categoryID, Size from coffee";
sqlite3_stmt *selectstmt;
if(sqlite3_prepare_v2(db, sql, -1, &selectstmt, NULL) == SQLITE_OK) {
while(sqlite3_step(selectstmt) == SQLITE_ROW) {
NSInteger primaryKey = sqlite3_column_int(selectstmt, 0);
Income *incomeObj = [[Income alloc] initWithPrimaryKey:primaryKey];
incomeObj.incomeName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(selectstmt, 1)];
incomeObj.isDirty = NO;
[rArray addObject:incomeObj];
[incomeObj release];
}
} else {
NSLog(#"sql-error in getIncoms: %s", sqlite3_errmsg(db));
}
sqlite3_finalize(selectstmt);
return rArray;
}
Now you could do something like that.
DBi *dbi = [[DBi alloc] init];
NSArray *incoms = [dbi getIncoms];
[dbi release];
hope, that should help
use this code
sqlite3 *database;
if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK)
{
////your Code
if(sqlite3_prepare_v2(database, [sqlStatement cStringUsingEncoding:NSUTF8StringEncoding], -1, &compiledStatement, NULL) == SQLITE_OK)
{
NSLog(#"%#",sqlStatement);
while(sqlite3_step(compiledStatement) == SQLITE_ROW)
{
//your code
}
}
sqlite3_finalize(compiledStatement);
sqlite3_close(database);
}
}
Use FMDB for you sqlite tasks. It's a bad practice to use sqlite calls everywhere in the application. Just search on google for FMDB Example you will find one. FMDB is much easier to implement then SQLIte because FMDB handles all the things.
It turns out I was calling the same SQL method in two different places in very quick succession before the statements had a chance to be finalised each time. I guess this caused some sort of overlap eventually leading to the statements becoming invalid. Thanks for all the help. I will definitely be using CoreData or FMDB next time.
I'm reading data from a sqlite database however in my detailed view one of the data items is not showing correctly. It show what looks like random memory i.e. UIDeviceRGB...(I have two strings, one that works one that doesn't). I can't work out why but when I run the debug it returns null.
Here is my code in HydratedDetailData:
if (SQLITE_DONE != sqlite3_step(detailStmt)) {
double add = sqlite3_column_double(detailStmt, 2);
NSString *address = [NSString stringWithFormat:#"%#", add];
self.ClubAddress = address;
[address release];
}
Any help work be greatly appreciated!
code from Clubs.m
#import "Clubs.h"
static sqlite3 *database = nil;
static sqlite3_stmt *detailStmt = nil;
#implementation Clubs
#synthesize clubID, clubName, ClubAddress, isDirty, isDetailViewHydrated;
+(void) getInitialDataToDisplay:(NSString *)dbPath {
SQLAppDelegate *appDelegate = (SQLAppDelegate *) [[UIApplication sharedApplication] delegate];
if (sqlite3_open([dbPath UTF8String], &database) == SQLITE_OK) {
const char *sql = "select clubID, clubName from clubNames";
sqlite3_stmt *selectstmt;
if (sqlite3_prepare_v2(database, sql, -1, &selectstmt, NULL) == SQLITE_OK) {
while (sqlite3_step(selectstmt)== SQLITE_ROW) {
NSInteger primaryKey = sqlite3_column_int(selectstmt, 0);
Clubs *clubObj = [[Clubs alloc] initWithPrimaryKey:primaryKey];
clubObj.clubName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(selectstmt, 1)];
clubObj.isDirty = NO;
[appDelegate.clubArray addObject:clubObj];
[clubObj release];
}
}
}
else
sqlite3_close(database);
}
+(void) finalizeStatements {
if (database) sqlite3_close(database);
}
-(id) initWithPrimaryKey:(NSInteger) pk {
[super init];
clubID = pk;
isDetailViewHydrated = NO;
return self;
}
-(void) hydrateDetailViewData {
if (isDetailViewHydrated) return;
if (detailStmt == nil) {
const char *sql = "Select ClubAddress from clubNames Where clubID = ?";
if (sqlite3_prepare_v2(database, sql, -1, &detailStmt, NULL) !=SQLITE_OK)
NSAssert1(0, #"Error while creating detail view statment. '%s'", sqlite3_errmsg(database));
}
sqlite3_bind_int(detailStmt, 1, clubID);
if (SQLITE_DONE != sqlite3_step(detailStmt)) {
double add = sqlite3_column_double(detailStmt, 0);
NSString *address = [NSString stringWithFormat:#"%d", add];
self.ClubAddress = address;
}
else
NSAssert1(0, #"Error while getting the address of club. '%s'", sqlite3_errmsg(database));
sqlite3_reset(detailStmt);
isDetailViewHydrated = YES;
}
-(void) dealloc {
[ClubAddress release];
[clubName release];
[super dealloc];
}
#end
i had such a problem for reading double values, some of values read right but some read as 0 ! i have tried many things but at last my problem was solved by defining variables globally. i have defined the locally in .m file but the solution was to define them in .h file.i hope it can solve yours too.
good luck
Perhaps if you used the %d formatter in your [NSString stringWithFormat:#"%#", add]; call.
(%# is generally for strings, %d is for doubles)
After our little discussion-athon, this should fix what ails you.
if (SQLITE_DONE != sqlite3_step(detailStmt)) {
char *db_text = sqlite3_column_text(detailStmt, 2);
NSString *address = [NSString stringWithUTF8String: db_text];
self.ClubAddress = address;
}
This will pull the text value from the database and convert it into an NSString*. (hopefully)....
I was successfully accessing my database to get a list of cities on the App launch. I tried running a second query against it right afterward to get the list of States but all that happens is that my app blows up with no usable error in the console (simply says "Program received signal: EXEC_BAD_ACCESS" and nothing more).
Here is the code, I was hoping someone could potentially explain to me what I'm doing wrong:
-(void) initializeDatabase{
// The database is stored in the application bundle
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:#"mydatabase.sqlite"];
// Open the database. The database was prepared outside the application.
if (sqlite3_open([path UTF8String], &database) == SQLITE_OK){
[self initializeCities:database];
[self initializeStates:database];
} else {
// Even though the open failed, call close to properly clean up resources.
sqlite3_close(database);
NSAssert1(0, #"Failed to open database with message '%s'.", sqlite3_errmsg(database));
// Additional error handling, as appropriate...
}
}
-(void) initializeCities:(sqlite3 *)db {
NSMutableArray *cityArray = [[NSMutableArray alloc] init];
self.cities = cityArray;
[cityArray release];
// Get the primary key for all cities.
const char *sql = "SELECT id FROM my_table ORDER BY state";
sqlite3_stmt *statement;
if (sqlite3_prepare_v2(db, sql, -1, &statement, NULL) == SQLITE_OK){
while (sqlite3_step(statement) == SQLITE_ROW){
int primaryKey = sqlite3_column_int(statement, 0);
City *city = [[City alloc] initWithPrimaryKey:primaryKey database:db];
[cities addObject:city];
[city release];
}
}
// "Finalize" the statement - releases the resources associated with the statement.
sqlite3_finalize(statement);
}
-(void) initializeStates:(sqlite3 *)db {
NSMutableArray *statesArray = [[NSMutableArray alloc] init];
self.states = statesArray;
[statesArray release];
// Get the primary key for all cities.
const char *sql = "SELECT DISTINCT state FROM my_table ORDER BY state";
sqlite3_stmt *statement;
if (sqlite3_prepare_v2(db, sql, -1, &statement, NULL) == SQLITE_OK){
// We "step" through the results - once for each row
while (sqlite3_step(statement) == SQLITE_ROW){
NSString *state;
state = (NSString *)sqlite3_column_text(statement, 0);
[states addObject:state];
[state release];
}
}
// "Finalize" the statement - releases the resources associated with the statement.
sqlite3_finalize(statement);
}
I can't debug this code as the debugger never hits my breakpoints at all.
If I remove the initializeStates method the app works as expected (albiet without a list of states).
You are releasing "state" without having allocated it. Try something like this:
while (sqlite3_step(statement) == SQLITE_ROW){
NSString *state = [[NSString alloc] initWithCString:(char*)sqlite3_column_text(statement, 0) encoding:NSASCIIStringEncoding];
//state = (NSString *)sqlite3_column_text(statement, 0);
[states addObject:state];
[state release];
}
Update: add cast above to fix compiler warning
Your problem is this:
NSString *state = (NSString *)sqlite3_column_text(statement, 0);
According to the documentation, sqlite3_column_text() returns a char*, not an NSString*.
Edit: You wouldn't have had this problem if you'd have used a wrapper ;)
I am having a problem with what I believe is a memory leak which after some time is causing my app to slow down. I have a sectioned uitableview that has sections of 'movie directors' with rows of thier movies in their particular section. To do this I am calling a data object (and passing it the section header) to return that section's data and populate the section rows. So I am calling that object a few times on the same view(numberOfRowsInSection, cellForRowAtIndexPath, and didSelectRowAtIndexPath) this happens for each section. Looking at Instruments, I believe the leak is coming from getDirectorsMovies:theDirector from Movies.m. Can anyone tell me what I am doing that is causing this leak. Any help would be greatly appreciated, I've been working on this for a few weeks. Below is some code to show what I am doing.
Thanks in advance!!!
//Movies.h
#import <Foundation/Foundation.h>
#import <sqlite3.h>
#import "Movie.h"
#interface Movies : NSObject {
}
- (NSMutableArray *) getDirectorsMovies:(NSString *)theDirector;
#end
//Movies.m //getDirectorsMovies:(NSString *)theDirector goes to the database, gets the directors movies, and returns them in an array
#import "Movies.h"
#implementation Movies
- (NSMutableArray *) getDirectorsMovies:(NSString *)theDirector
{
sqlite3 *database;
NSString *databaseName = #"Movies.sql";
NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDir = [documentPaths objectAtIndex:0];
NSString *databasePath = [documentsDir stringByAppendingPathComponent:databaseName];
NSMutableArray *theDirectorsMovies = [[NSMutableArray alloc] init];
if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) {
const char *sqlStatement = "select * from movies where lastname = ? order by lastname, movie";
sqlite3_stmt *compiledStatement;
if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) {
sqlite3_bind_text(compiledStatement, 1, [theDirector UTF8String], -1, SQLITE_TRANSIENT);
while(sqlite3_step(compiledStatement) == SQLITE_ROW) {
NSString *aLastName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 1)];
NSString *aDirector = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)];
NSString *aMovie = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 3)];
Movie *movie = [[Movie alloc] initWithName:aMovie lastname:aLastName director:aDirector];
[theDirectorsMovies addObject:movie];
[movie release];
}
}
sqlite3_finalize(compiledStatement);
}
sqlite3_close(database);
return theDirectorsMovies;
[theDirectorsMovies release];
}
#end
//Calling getDirectorsMovies:(NSString *)theDirector
MoviesAppDelegate *appDelegate = (MoviesAppDelegate *)[[UIApplication sharedApplication] delegate];
Director *director = (Director *)[appDelegate.director objectAtIndex:indexPath.section];//appDelegate.director IS A MSMutableArray defined in the AppDelegate
self.theMovies = nil;//THIS IS A MSMutableArray defined in the AppDelegate
Movies *directorMovies = [[Movies alloc] init];
self.theMovies = [directorMovies getDirectorMovies:director.lastname];
[directorMovies release];
Movie *movie = (Movie *)[theMovies objectAtIndex:indexPath.row];
//do whatever with the data
[movie release];
You have this:
return theDirectorsMovies;
[theDirectorsMovies release];
Nothing happens after the return statement, so your call to release will never happen. It was for this very reason that AutoreleasePools were invented (and patented). Simply do:
return [theDirectorsMovies autorelease];
And your memory leak will go away.
There are a number of potential issues here it would be useful to see the init method for Movie as that may be where the issue is. Also you should have an autorelease on the NSMutableArray.
In my sqlite code I have the following statement normally before the sqlite3_finalize call
sqlite3_clear_bindings(compiledStatement);
That call cleared up a lot of issues for my code.