I have an indexPath.row that is 1 and logs 1(when using NSLog). If I call indexPath.row-1 (should return 0) it returns 4294967295.
I'm trying to return an objectAtIndex:indexPath.row-1 but that's when I get 4294967295.
Any ideas?
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// Configure the cell...
Singleton *singleton = [Singleton sharedSingleton];
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
if ([[prefs objectForKey:#"isYes"]boolValue] == 1 && randomMarker != 100)
{
//sets cell image
UIImageView *imgView = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,98,100)];
imgView.image = [UIImage imageNamed:#"stackoverflow.png"];
cell.imageView.image = imgView.image;
//sets cell text
cell.textLabel.text = #"Text";
self.checkedInCount == 100;
}
else if ([[prefs objectForKey:#"isYes"]boolValue] == 1 && randomMarker == 100)
{
//gets cell and cleans up cell text
NSLog(#"%#", indexPath.row);
NSString *title = [[[singleton linkedList]objectAtIndex:(indexPath.row-1)]objectForKey:#"desc"];
When you attempt to give an unsigned int (NSUInteger) a negative value, it often returns a very large positive value instead.
You are calling
NSString *tempDesc = [[[singleton linkedList]objectAtIndex:indexPath.row-1]objectForKey:#"desc"];
when indexPath.row has value 0, so the translation is:
NSString *tempDesc = [[[singleton linkedList]objectAtIndex:-1]objectForKey:#"desc"];
Since objectAtIndex: takes an unsigned integer as its parameter, -1 is converted to a garbage value of 4294967295.
To avoid this problem, don't subtract 1 from 0 by checking first that indexPath.row is positive.
Here's another problem:
NSLog(#"%#", indexPath.row);
This should instead read:
NSLog(#"%u", indexPath.row);
NSLog(#"%#", indexPath.row);
You shold use %d for integer as indexPath.row will return an integer
Use
NSLog(#"%d", indexPath.row);
Related
I have a UITableView that should have 33 rows. Each row represents a specific time slot in a day. When the view that holds the table view loads, I need it to populate each row accordingly.
I have an array of reservation objects that gets passed to the view. Each reservation contains a slot number, a reservation name and the duration of the reservation in slots.
What is the best way to populate the table, I am currently iterating through the array of reservations in the - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath method.
This is not giving me the results or the behavior I am expecting. The performance is extremly poor as it keeps iterating through loops and cells that shouldn't be blue are blue after scrolling. What is the best way to approach this? I have included the code below.
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return 33;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
NSString *timeStamp = [NSString stringWithFormat:#"%.2f", (indexPath.row + 14.0 ) / 2.0];
timeStamp = [timeStamp stringByReplacingOccurrencesOfString:#".50" withString:#":30"];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.textLabel.text = [NSString stringWithFormat:#"%#: ", timeStamp];
for (Reservation *temp in bookingsArray) {
if ((temp.slotNumber - 1) == indexPath.row) {
cell.textLabel.text = [NSString stringWithFormat:#"%#: %#", timeStamp, temp.reservationName];
cell.contentView.backgroundColor = [UIColor blueColor];
}
for (NSNumber *tempNo in temp.slotIdentifiers) {
if ([tempNo intValue] -1 == indexPath.row) {
//cell.textLabel.text = [NSString stringWithFormat:#"%#: Booked", timeStamp];
cell.contentView.backgroundColor = [UIColor blueColor];
}
}
}
return cell;
}
UPDATE
Trying the following gives me strange behaviour where all the cells turn blue after I start scrolling.
- (void)viewDidLoad
{
[super viewDidLoad];
bookManager = appDelegate.bookingManager;
bookingsArray = [[NSArray alloc] initWithArray:[bookManager getBookingsForCourt:1 onDate:[NSDate date]]];
namesArray = [[NSMutableDictionary alloc] init];
slotIndexSet = [NSMutableIndexSet indexSet];
for (int c = 0; c < 33; c++) {
[namesArray setObject:#"Available" forKey:[NSNumber numberWithInt:c]];
}
for (Reservation *temp in bookingsArray) {
[namesArray setObject:temp.reservationName forKey:[NSNumber numberWithInt:temp.slotNumber]];
for (NSNumber *slotNo in temp.slotIdentifiers) {
[slotIndexSet addIndex:[slotNo intValue] + 1];
}
}
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
NSString *timeStamp = [NSString stringWithFormat:#"%.2f", (indexPath.row + 14.0 ) / 2.0];
timeStamp = [timeStamp stringByReplacingOccurrencesOfString:#".50" withString:#":30"];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.textLabel.text = [NSString stringWithFormat:#"%#: ", timeStamp];
cell.textLabel.text = [namesArray objectForKey:[NSNumber numberWithInt:indexPath.row]];
if ([slotIndexSet containsIndex:indexPath.row]) {
cell.contentView.backgroundColor = [UIColor blueColor];
}
return cell;
}
You need to do two things to speed this up:
Convert bookingsArray to a bookingBySlotNumber array in such a way that the object at index i has slotNumber - 1 equal to i. You can do it by iterating over the original bookings array when you receive it.
Create a NSIndexSet called isBookedBySlotNumber containing indexes of items that have been booked. You can prepare it by going through all Reservation.slotIdentifiers, and marking the indexes of isBookedBySlotNumber for items that have been booked.
With these two pre-processed items in place, you can eliminate the nested loops altogether: the outer one will be replaced by a lookup in bookingBySlotNumber, and the inner one - by a loopup in isBookedBySlotNumber.
I have a tableview which has a list of options the user has selcected( It is an edit page ).
the tableview looks as below
Apple UITableViewCellAccessoryCheckmark
Orange UITableViewCellAccessoryNone
Pineapple UITableViewCellAccessoryCheckmark Banana
UITableViewCellAccessoryNone
- (void)viewDidLoad {
self.mySavedFruitsArray = [myDBOperations getMyFruitsList:[appDelegate getDBPath]:self.myId];
}
/ Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
(NSIndexPath *)indexPath
//-------------------------------------------------------------------------------
{
static NSString *CellIdentifier = #"PoemTypeCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:#"MyIdentifier"]autorelease];
}
NSDictionary *aDict = [self.myFruitsArr objectAtIndex:indexPath.row];
NSString *aValue = [aDict objectForKey:#"value"];
NSString *aId = [aDict objectForKey:#"key"];
cell.textLabel.text = aValue;
cell.accessoryType = UITableViewCellAccessoryNone;
NSDictionary *aSavedDict = [self.mySavedFruitsArray objectAtIndex:indexPath.row];
NSString *Value = [aSavedDict objectForKey:#"value"];
NSString *Id = [aSavedDict objectForKey:#"key"];
if ( aId == Id ){
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}else
{
cell.accessoryType = UITableViewCellAccessoryNone;
}
return cell;
}
mySavedFruitsArray - it holds the user selected fruits.
myFruitsArr - this has common list of fruits
now i would like to know how to display UITableViewCellAccessoryCheckmark for cell which matches with mySavedFruitsArray.
I mean , in this edit view i want to display the fruits list with user selected option.
Pls let me know how to do that.
I tried like this, but no use.
/ Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
(NSIndexPath *)indexPath
//-------------------------------------------------------------------------------
{
static NSString *CellIdentifier = #"PoemTypeCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:#"MyIdentifier"]autorelease];
}
NSDictionary *aDict = [self.myFruitsArr objectAtIndex:indexPath.row];
NSString *aValue = [aDict objectForKey:#"value"];
NSString *aId = [aDict objectForKey:#"key"];
cell.textLabel.text = aValue;
cell.accessoryType = UITableViewCellAccessoryNone;
NSDictionary *aSavedDict = [self.mySavedFruitsArray objectAtIndex:indexPath.row];
NSString *Value = [aSavedDict objectForKey:#"value"];
NSString *Id = [aSavedDict objectForKey:#"key"];
if ( aId == Id ){
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}else
{
cell.accessoryType = UITableViewCellAccessoryNone;
}
return cell;
}
pls note self.mySavedFruitsArray may not be equal to myFruitsArr always ( because user may select only one fruit).
if ( aId == Id ){
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}else
{
cell.accessoryType = UITableViewCellAccessoryNone;
}
string comparison is wrong. You should compare strings this way:
if([aId isEqualToString:Id]) {
....
}
instead of checking if ( aId == Id ) which compares the strings as identical objects,
use if ([aID isEqualToString:Id]) which compares strings
In a version downloaded yesterday (6/8/14), UITableViewCellAccessoryCheckmark and UITableViewCellAccessoryNone is not valid. It was throwing compiler errors for me. I think you are supposed to use it as an enum, like so:
if item.completed {
cell!.accessoryType = UITableViewCellAccessoryType.Checkmark
} else {
cell!.accessoryType = UITableViewCellAccessoryType.None
}
With this change, my code compiles and the behavior appears in the simulator.
Sorry I don't know which version to look up (UIKit?), I'm new to iOS development.
i have a UItableView and i have two buttons on each cell. You can add or subtract 1 from the cell's textLabel. I add the cells current value +1 with this:
- (IBAction)addLabelText:(id)sender{
num = [NSString stringWithFormat:#"%d",[cell.textLabel.text intValue] +1];//<--- num is an NSNumber
number = [[NSMutableArray alloc]initWithObjects:num, nil];//<---- number is an NSMutableArray
[myTableView reloadData];
}
and I am trying to subtract the text and store it in an array with this:
- (IBAction)subtractLabelText:(id)sender
{
if ( [[cell.textLabel text] intValue] == 0){
num = [NSString stringWithFormat:#"%d",[num intValue] +0];
[number addObject:num];
[myTableView reloadData];
}
else{
num = [NSString stringWithFormat:#"%d",[num intValue] -1];
[number addObject:num];
[myTableView reloadData];
}
}
and im trying to set the cell.textLabel.text in the cellForRow like this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath
{
static NSString *identifier = #"Cell";
cell = [tableView dequeueReusableCellWithIdentifier:identifier];
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier] autorelease];
}
cell.textLabel.text = [number objectAtIndex:indexPath.row];//<---IM USING THIS LINE TO SET THE NEW TEXTLABEL
cell.textLabel.text = #"1";
return cell;
}
MY PROBLEM
So, the addition works, but the subtraction does not. It doesnt work at all when i press the button on the cell. Thanks in advance!!
At the risk of pointing out the obvious... you seem to have hard-coded the text property to #"1".
cell.textLabel.text = [number objectAtIndex:indexPath.row];//<---IM USING THIS LINE TO SET THE NEW TEXTLABEL
cell.textLabel.text = #"1";
The first line is probably doing what you think... but then you're immediately changing it back to #"1".
EDIT - Based on clarification in comments, here's what I think you want to do. I will modify your own code as posted.
Note that I put my addition into viewDidLoad as an example. You could do this in init, or any number of other places, at whatever point you know how many cells you want to show.
- (void)viewDidLoad {
self.number = [[[NSMutableArray alloc] init] autorelease];
for (int i = 0; i < [HOW MANY CELLS DO YOU WANT?]; i++) {
[self.number addObject:#"1"];
}
[myTableView reloadData];
}
- (IBAction)addLabelText:(id)sender {
// Note that I'm assuming here that your button is a direct child of the cell.
// If not, you'll need to change this.
UITableViewCell *cell = [sender superview];
NSInteger newNumber = [cell.textLabel.text intValue] + 1;
NSString *newNumberString = [NSString stringWithFormat:#"%d", newNumber];
[self.number replaceObjectAtIndex:cell.tag withObject:newNumberString];
[myTableView reloadData];
}
- (IBAction)subtractLabelText:(id)sender {
// Note that I'm assuming here that your button is a direct child of the cell.
// If not, you'll need to change this.
UITableViewCell *cell = [sender superview];
NSInteger newNumber = [cell.textLabel.text intValue] - 1;
newNumber = (newNumber < 0) ? 0 : newNumber;
NSString *newNumberString = [NSString stringWithFormat:#"%d", newNumber];
[self.number replaceObjectAtIndex:cell.tag withObject:newNumberString];
[myTableView reloadData];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *identifier = #"Cell";
cell = [tableView dequeueReusableCellWithIdentifier:identifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier] autorelease];
}
cell.tag = indexPath.row; // Important for identifying the cell easily later
cell.textLabel.text = [self.number objectAtIndex:indexPath.row];
return cell;
}
I don't want to get too much more in depth, but I would recommend you take a look at reloading only the cell modified, instead of calling [myTableView reloadData] every time.
I started this project with a simple plist of a dictionary with two arrays of strings. I now want to add more information and want to use this plist structure:
Root - Dictionary - (2 items)
Standard - Array - (3 items)
Item 0 - Dictionary - (4 items)
Color - String - Red
Rvalue - String - 255
Gvalue - String - 0
Bvalue - String - 0
Sorry about typing in the plist but the site would not let me post an image
I know that the RGB values could be numbers instead of strings but I have a reason for them being strings.
This is the code I used to read the simple plist:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger section = [indexPath section];
NSUInteger row = [indexPath row];
NSString *key = [keys objectAtIndex:section];
NSArray *colorSection = [colors objectForKey:key];
static NSString *SectionsTableIdentifier = #"SectionsTableIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:SectionsTableIdentifier];
if(cell == nil){
cell=[[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier: SectionsTableIdentifier] autorelease];
}
cell.textLabel.text = [colorSection objectAtIndex:row];
[cell setAccessoryType:UITableViewCellAccessoryDetailDisclosureButton]; //add disclosure button to rows
return cell;
}
My question is what is the specific code to retrieve the contents of the color dictionaries to get the Colors for the cell.textLabel.text and also read the RGB values to add a subtitle. I've been working on this for several days and have read references and lots of examples and unfortunately can't solve the problem. Your assistance will be greatly appreciated.
So providing you have your Standard - Array stored against a Array you've defined in your .h file then something like this would work. In this example the array is stored against self.coloursArray.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *SectionsTableIdentifier = #"SectionsTableIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:SectionsTableIdentifier];
if(cell == nil){
cell=[[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier: SectionsTableIdentifier] autorelease];
}
NSString* ColourString = [[self.coloursArray objectAtIndex:indexPath.row] valueForKey:#"Colour"];
NSString* rValue = [[self.coloursArray objectAtIndex:indexPath.row] valueForKey:#"Rvalue"];
NSString* gValue = [[self.coloursArray objectAtIndex:indexPath.row] valueForKey:#"Gvalue"];
NSString* bValue = [[self.coloursArray objectAtIndex:indexPath.row] valueForKey:#"Bvalue"];
cell.textLabel.text = ColourString;
NSString* subCellString = [NSString stringWithFormat:#"%#:%#:%#", rValue, gValue, bValue];
}
Hopefully that'll give a a hand.
First, do not use -[UITableViewCell initWithFrame:reuseIdentifier:]. It has been deprecated and will give you a warning, plus it will make your subtitle harder to implement. This code is a modified version of yours which loads the information, sets the title to the Color property, and sets the subtitle to a string containing the Rvalue, Gvalue, and Bvalue properties.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger section = [indexPath section];
NSUInteger row = [indexPath row];
NSString *key = [keys objectAtIndex:section];
NSArray *colorSection = [colors objectForKey:key];
static NSString *SectionsTableIdentifier = #"SectionsTableIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:SectionsTableIdentifier];
if(cell == nil) {
cell=[[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier: SectionsTableIdentifier] autorelease];
}
NSDictionary *color = [colorSection objectAtIndex:row];
cell.textLabel.text = [color objectForKey:#"Color"];
cell.detailTextLabel.text = [NSString stringWithFormat:#"%#, %#, %#",[color objectForKey:#"Rvalue"],[color objectForKey:#"Gvalue"],[color objectForKey:#"Bvalue"]];
[cell setAccessoryType:UITableViewCellAccessoryDetailDisclosureButton]; //add disclosure button to rows
return cell;
}
My UITableView has up to 50 rows in each section, populated by a plist dictionary which contains arrays (sections) which contains arrays (row objects) which contains two strings (row title / filename and file extension).
Select row 1 - 25 (item 0-24) and everything behaves normally. But select a row greater than 26 (item 25) and the app crashes. I'm a novice at all this and I tried researching for the answer but I'm at a loss for how to research this. Can tables only have 25 rows per section?
Any ideas? Thank you!
Jon
- (void)tableView:(UITableView *)tableView
didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger section = [indexPath section];
NSUInteger row = [indexPath row];
NSMutableString *key = [categories objectAtIndex:section];
NSMutableArray *sound = [categoriesSounds objectForKey:key];
NSMutableString *soundName = [[sound objectAtIndex: row] objectAtIndex: 0];
NSMutableString *soundOfType = [[sound objectAtIndex: row] objectAtIndex: 1];
if (leftSwitch.on == YES) {
showLeft.text = soundName;
left = [[NSBundle mainBundle] pathForResource:(#"%#", soundName) ofType:(#"%#", soundOfType)];
AudioServicesCreateSystemSoundID((CFURLRef)[NSURL
fileURLWithPath:left], &soundNegZ);
AudioServicesPlaySystemSound (soundNegZ);
if (indexPath != leftOldIndexPath) {
UITableViewCell *newCell = [tableView cellForRowAtIndexPath:indexPath];
newCell.accessoryType = UITableViewCellAccessoryCheckmark;
UITableViewCell *oldCell = [tableView cellForRowAtIndexPath:leftOldIndexPath];
oldCell.accessoryType = UITableViewCellAccessoryNone;
leftOldIndexPath = indexPath;
}
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
if (downSwitch.on == YES) {
showDown.text = soundName;
down = [[NSBundle mainBundle] pathForResource:(#"%#", soundName) ofType:(#"%#", soundOfType)];
AudioServicesCreateSystemSoundID((CFURLRef)[NSURL
fileURLWithPath:down], &soundNegX);
AudioServicesPlaySystemSound (soundNegX);
if (indexPath != downOldIndexPath) {
UITableViewCell *newCell = [tableView cellForRowAtIndexPath:indexPath];
newCell.accessoryType = UITableViewCellAccessoryCheckmark;
UITableViewCell *oldCell = [tableView cellForRowAtIndexPath:downOldIndexPath];
oldCell.accessoryType = UITableViewCellAccessoryNone;
downOldIndexPath = indexPath;
}
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
if (rightSwitch.on == YES) {
showRight.text = soundName;
right = [[NSBundle mainBundle] pathForResource:(#"%#", soundName) ofType:(#"%#", soundOfType)];
AudioServicesCreateSystemSoundID((CFURLRef)[NSURL
fileURLWithPath:right], &soundPosX);
AudioServicesPlaySystemSound (soundPosX);
if (indexPath != rightOldIndexPath) {
UITableViewCell *newCell = [tableView cellForRowAtIndexPath:indexPath];
newCell.accessoryType = UITableViewCellAccessoryCheckmark;
UITableViewCell *oldCell = [tableView cellForRowAtIndexPath:rightOldIndexPath];
oldCell.accessoryType = UITableViewCellAccessoryNone;
rightOldIndexPath = indexPath;
}
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
}
For "EXC_BAD_ACCESS" in the console, this is the debugger output (error trace is marked with asterisks):
0x91a6cec0 <+0000> mov 0x8(%esp),%ecx
0x91a6cec4 <+0004> mov 0x4(%esp),%eax
0x91a6cec8 <+0008> cmp $0xfffeb010,%ecx
0x91a6cece <+0014> je 0x91a6cf35 <objc_msgSend+117>
0x91a6ced0 <+0016> test %eax,%eax
0x91a6ced2 <+0018> je 0x91a6cf1a <objc_msgSend+90>
0x91a6ced4 <+0020> mov (%eax),%edx
0x91a6ced6 <+0022> push %edi
**0x91a6ced7 <+0023> mov 0x20(%edx),%edi**
0x91a6ceda <+0026> push %esi
0x91a6cedb <+0027> mov (%edi),%esi
0x91a6cedd <+0029> mov %ecx,%edx
0x91a6cedf <+0031> shr $0x2,%edx
0x91a6cee2 <+0034> and %esi,%edx
0x91a6cee4 <+0036> mov 0x8(%edi,%edx,4),%eax
0x91a6cee8 <+0040> test %eax,%eax
0x91a6ceea <+0042> je 0x91a6cef5 <objc_msgSend+53>
0x91a6ceec <+0044> cmp (%eax),%ecx
0x91a6ceee <+0046> je 0x91a6cf00 <objc_msgSend+64>
0x91a6cef0 <+0048> add $0x1,%edx
0x91a6cef3 <+0051> jmp 0x91a6cee2 <objc_msgSend+34>
0x91a6cef5 <+0053> pop %esi
0x91a6cef6 <+0054> pop %edi
0x91a6cef7 <+0055> mov 0x4(%esp),%eax
0x91a6cefb <+0059> mov (%eax),%eax
0x91a6cefd <+0061> jmp 0x91a6cf09 <objc_msgSend+73>
0x91a6ceff <+0063> nop
0x91a6cf00 <+0064> mov 0x8(%eax),%eax
0x91a6cf03 <+0067> pop %esi
0x91a6cf04 <+0068> pop %edi
0x91a6cf05 <+0069> xor %edx,%edx
0x91a6cf07 <+0071> jmp *%eax
0x91a6cf09 <+0073> sub $0x4,%esp
0x91a6cf0c <+0076> push %ecx
0x91a6cf0d <+0077> push %eax
0x91a6cf0e <+0078> call 0x91a6d33f <_class_lookupMethodAndLoadCache>
0x91a6cf13 <+0083> add $0xc,%esp
0x91a6cf16 <+0086> xor %edx,%edx
0x91a6cf18 <+0088> jmp *%eax
0x91a6cf1a <+0090> call 0x91a6cf1f <objc_msgSend+95>
0x91a6cf1f <+0095> pop %edx
0x91a6cf20 <+0096> mov 0xe79d961(%edx),%eax
0x91a6cf26 <+0102> test %eax,%eax
0x91a6cf28 <+0104> je 0x91a6cf30 <objc_msgSend+112>
0x91a6cf2a <+0106> mov %eax,0x4(%esp)
0x91a6cf2e <+0110> jmp 0x91a6ced4 <objc_msgSend+20>
0x91a6cf30 <+0112> mov $0x0,%edx
0x91a6cf35 <+0117> ret
0x91a6cf36 <+0118> nopw %cs:0x0(%eax,%eax,1)
My cellForRowAtIndexPath method:
- (UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger section = [indexPath section];
NSUInteger row = [indexPath row];
NSString *key = [categories objectAtIndex:section];
NSArray *nameSection = [categoriesSounds objectForKey:key];
static NSString *SectionsTableIdentifier = #"SectionsTableIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:
SectionsTableIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc]
initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:SectionsTableIdentifier] autorelease];
}
cell.textLabel.text = [[nameSection objectAtIndex:row] objectAtIndex: 0];
if (leftSwitch.on == YES){
NSUInteger leftRow = [leftOldIndexPath row];
NSUInteger leftSection = [leftOldIndexPath section];
cell.accessoryType = (row == leftRow && section == leftSection && leftOldIndexPath !=nil) ?
UITableViewCellAccessoryCheckmark : UITableViewCellAccessoryNone;
}
if (downSwitch.on == YES){
NSUInteger downRow = [downOldIndexPath row];
NSUInteger downSection = [downOldIndexPath section];
cell.accessoryType = (row == downRow && section == downSection && downOldIndexPath !=nil) ?
UITableViewCellAccessoryCheckmark : UITableViewCellAccessoryNone;
}
if (rightSwitch.on == YES){
NSUInteger rightRow = [rightOldIndexPath row];
NSUInteger rightSection = [rightOldIndexPath section];
cell.accessoryType = (row == rightRow && section == rightSection && rightOldIndexPath !=nil) ?
UITableViewCellAccessoryCheckmark : UITableViewCellAccessoryNone;
}
return cell;
}
From analysing your code, I can see a few places where you can be failing.
First of all:
NSMutableString *soundName = [[sound objectAtIndex: row] objectAtIndex: 0];
NSMutableString *soundOfType = [[sound objectAtIndex: row] objectAtIndex: 1];
Do you have more than 25 elements in the sound array?
Second of all:
if (indexPath != downOldIndexPath) {
What is downOldIndexPath? Are you sure that if you pass it to this method
UITableViewCell *oldCell = [tableView cellForRowAtIndexPath:downOldIndexPath];
it is a correct index path?
When your app crashes do you see any error messages logged in the debugger console? (If it's not viewable whilst you debug your application select the Run menu -> Console menu option in XCode). You should see some log entries in here that will help to point you in the right direction.
I have 101 rows in my current project. As far as i know there isn't a limit.
As for the crash, can you give us more info? Like a stack trace? Console output?
If you were accessing more elements than the array held, you would get an out of bounds exception - not a EX_BAD_ACCESS crash.
That means you are trying to access memory you have released. There are two possibilities:
1) The item you are pulling out of the array, has been released. This is pretty unlikely as you would have had to do extra releases to get rid of something held in an array.
2) (most likely) You have released one of the arrays you are trying to get data from - or more accurately, you get the array from somewhere and then forget to retain it (since most things given to you by other methods are auto-released).
I'm having this same problem, I see you've solved it by the following:
Thanks Eddie, NSZombieEnabled pointed me in the right direction and I was able to fix the problem. Turned out my index path retain count needed to be increased by 1 in cellForRowAtIndexPath. – Jonathan Cohen Jan 25 at 18:00
Sorry I'm a bit new to iPhone programming, what does this mean exactly?
I've tried a few things and they all seem to work I'm just wondering which is the correct way!?
I have tried this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CheckMarkCellIdentifier = #"CheckMarkCellIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier: CheckMarkCellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc]
initWithStyle:UITableViewCellStyleSubtitle
reuseIdentifier:CheckMarkCellIdentifier] autorelease];
}
// need to retain to stop this crashing with rows > ~26
[indexPath retain];
NSUInteger row = [indexPath row];
NSUInteger oldRow = [lastIndexPath row];
// Print the text
cell.textLabel.text = [itemTextList objectAtIndex:row];
// Print the detail text
cell.detailTextLabel.text = [itemDetailTextList objectAtIndex:row];
cell.accessoryType = (row == oldRow && lastIndexPath != nil) ? UITableViewCellAccessoryCheckmark : UITableViewCellAccessoryNone;
return cell;
}
Also (separately) I've tried both of these:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger newRow = [indexPath row];
NSUInteger oldRow = (lastIndexPath != nil) ? [lastIndexPath row] : -1;
if (newRow != oldRow) {
UITableViewCell *newCell = [tableView cellForRowAtIndexPath: indexPath];
newCell.accessoryType = UITableViewCellAccessoryCheckmark;
UITableViewCell *oldCell = [tableView cellForRowAtIndexPath: lastIndexPath];
oldCell.accessoryType = UITableViewCellAccessoryNone;
// retain indexPath to use as last index path
lastIndexPath = [indexPath retain];
}
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
and
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger newRow = [indexPath row];
NSUInteger oldRow = (lastIndexPath != nil) ? [lastIndexPath row] : -1;
if (newRow != oldRow) {
UITableViewCell *newCell = [tableView cellForRowAtIndexPath: indexPath];
newCell.accessoryType = UITableViewCellAccessoryCheckmark;
UITableViewCell *oldCell = [tableView cellForRowAtIndexPath: lastIndexPath];
oldCell.accessoryType = UITableViewCellAccessoryNone;
// get a copy to use as last index path
lastIndexPath = [indexPath copy];
}
[tableView deselectRowAtIndexPath:indexPath animated:YES];
}
Now I'm wavering towards the last [indexPath copy], is this the correct way to do it from a memory management point of view? Or does it not really matter whether I retain or copy it?
Thanks,
Matt.