Question

我一直在靠墙撞墙几天，需要一些帮助。我觉得我在做一些非常愚蠢的事情，但我找不到问题。这是表视图的控制器。我把SQL放在一行以简化它，作为此错误的故障排除的一部分。通常，它将位于模型类中的存取方法中。

它通过SQL读取就好了。查找这两个对象，将它们加载到todaysWorkout数组中，然后为表视图构建单元格。表视图实际上出现在scree上，然后抛出EXC_BAD_ACCESS。

我跑了乐器，它显示以下内容：

0 CFString Malloc 1 00：03.765 0x3946470 176基础 - [NSPlaceholderString initWithFormat：locale：arguments：]

1 CFString Autorelease 00：03.765 0x3946470 0 Foundation NSRecordAllocationEvent

2 CFString CFRelease 0 00：03.767 0x3946470 0带它 - [WorkoutViewController viewDidLoad]

3 CFString Zombie -1 00：03.917 0x3946470 0 Foundation NSPopAutoreleasePool

以下是控制器的源代码。我把它全部放在那里以防万一有什么东西导致问题。我真诚地感谢我能得到的任何帮助：

HEADER：

#import <UIKit/UIKit.h>
#import <sqlite3.h>
#import "NoteCell.h"
#import "BIUtility.h"
#import "Bring_ItAppDelegate.h"
#import "MoveListViewController.h"


@class MoveListViewController;
@class BIUtility;

@interface WorkoutViewController : UITableViewController {
    NSMutableArray *todaysWorkouts;
    IBOutlet NoteCell *woNoteCell;
    MoveListViewController *childController;
    NSInteger scheduleDay;
    BIUtility *bi;
}

@property (nonatomic, retain) NSMutableArray *todaysWorkouts;
@property (nonatomic, retain) NoteCell *woNoteCell;
@property (nonatomic,retain) BIUtility *bi;

//@property (nonatomic, retain) SwitchCell *woSwitchCell;

@end

CLASS：

#import "WorkoutViewController.h"
#import "MoveListViewController.h"
#import "Profile.h"

static sqlite3 *database = nil;

@implementation WorkoutViewController
@synthesize todaysWorkouts;
@synthesize woNoteCell;
@synthesize bi;

//@synthesize woSwitchCell;


- (void)viewDidLoad {
    [super viewDidLoad];


 bi = [[BIUtility alloc] init];


 todaysWorkouts = [[NSMutableArray alloc] init];

 NSString *query;
 sqlite3_stmt *statement;

 //open the database
 if (sqlite3_open([[BIUtility getDBPath] UTF8String], &database) != SQLITE_OK) {
  sqlite3_close(database);
  NSAssert(0, @"Failed to opendatabase");
 }

 query = [NSString stringWithFormat:@"SELECT IWORKOUT.WOINSTANCEID, IWORKOUT.WORKOUTID, CWORKOUTS.WORKOUTNAME FROM CWORKOUTS JOIN IWORKOUT ON IWORKOUT.WORKOUTID = CWORKOUTS.WORKOUTID AND DATE = '%@'", [BIUtility todayDateString]];
 if (sqlite3_prepare_v2(database, [query UTF8String], -1, &statement, nil) == SQLITE_OK) {
  while (sqlite3_step(statement) == SQLITE_ROW) {
   Workout *wo = [[Workout alloc] init];
   wo.woInstanceID = sqlite3_column_int(statement, 0);
   wo.workoutID = sqlite3_column_int(statement, 1);
   wo.workoutName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(statement, 2)];
   [todaysWorkouts addObject:wo];    
   [wo release];    
  }
  sqlite3_finalize(statement);

 } 
 if(database) sqlite3_close(database);

 [query release];




}



- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
 //todaysWorkouts = [BIUtility todaysScheduledWorkouts];
 static NSString *noteCellIdentifier = @"NoteCellIdentifier";

 UITableViewCell *cell;


 if (indexPath.section < ([todaysWorkouts count])) {
  cell = [tableView dequeueReusableCellWithIdentifier:@"OtherCell"];
  if (cell == nil) {
   cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier: @"OtherCell"] autorelease];
   cell.accessoryType = UITableViewCellAccessoryNone;
  } 
  if (indexPath.row == 0) {
   Workout *wo = [todaysWorkouts objectAtIndex:indexPath.section];   
   [cell.textLabel setText:wo.workoutName];
  } else {
   [cell.textLabel setText:@"Completed?"];
   [cell.textLabel setFont:[UIFont fontWithName:@"Arial" size:15]];
   [cell.textLabel setTextColor:[UIColor blueColor]];
  }

 } else { 
  cell = (NoteCell *)[tableView dequeueReusableCellWithIdentifier:noteCellIdentifier];
  if (cell == nil) {
   NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"NoteCell" owner:self options:nil];
   cell = [nib objectAtIndex:0];
  }
 }


 return cell; 

 //[cell release];
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
 NSUInteger row = [indexPath row];

 if (indexPath.section < ([todaysWorkouts count]) && (row == 0)) {
  MoveListViewController *moveListController = [[MoveListViewController alloc] initWithStyle:UITableViewStylePlain];
  moveListController.workoutID = [[todaysWorkouts objectAtIndex:indexPath.section] workoutID];
  moveListController.workoutName = [[todaysWorkouts objectAtIndex:indexPath.section] workoutName];
  moveListController.woInstanceID = [[todaysWorkouts objectAtIndex:indexPath.section] woInstanceID];


  NSLog(@"Workout Selected: %@", [[todaysWorkouts objectAtIndex:indexPath.section] workoutName]);
  Bring_ItAppDelegate *delegate = [[UIApplication sharedApplication] delegate];
  [delegate.workoutNavController pushViewController:moveListController animated:YES];
 } else {


  UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath]; 
  if (indexPath.section < ([todaysWorkouts count]) && (row == 1)) {
   if (cell.accessoryType == UITableViewCellAccessoryNone) {
    cell.accessoryType = UITableViewCellAccessoryCheckmark;
   }
   else {
    cell.accessoryType = UITableViewCellAccessoryNone;
   }
  }
 }
 [tableView deselectRowAtIndexPath:indexPath animated:YES];
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
 NSInteger h = 35;
 return h;
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
 return ([todaysWorkouts count] + 1);
 //return ([todaysWorkouts count]);

}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {

 if (section < ([todaysWorkouts count])) {
  return 2;
 } else { 
  return 1;
 }


}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {

 if (section < ([todaysWorkouts count])) {
  return @"Workout";
 } else { 
  return @"How Was Your Workout?";
 }

}


- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


- (void)dealloc {
    [todaysWorkouts release];
 [bi release];
 [super dealloc];
}


@end

Answer 1

您正在发布查询，但 stringWithFormat 方法将其标记为自动释放。

当运行循环再次释放时，它已经被您的代码释放，从而抛出了EXC_BAD_ACCESS异常。

仅发布保留，复制， alloc 或 new 的对象。

Answer 2

罪魁祸首：

NSString *query;
query = [NSString stringWithFormat:@"SELECT IWORKOUT.WOINSTANCEID, IWORKOUT.WORKOUTID, CWORKOUTS.WORKOUTNAME FROM CWORKOUTS JOIN IWORKOUT ON IWORKOUT.WORKOUTID = CWORKOUTS.WORKOUTID AND DATE = '%@'", [BIUtility todayDateString]];
[query release];

query未被保留，但您正在发布它。当自动释放池释放它时，您将偶然发现EXC_BAD_ACCESS错误以进行过度释放。

Answer 3

以下行创建一个自动释放的NSString，其保留计数为1

query = [NSString stringWithFormat:@"SELECT IWORKOUT.WOINSTANCEID, IWORKOUT.WORKOUTID, CWORKOUTS.WORKOUTNAME FROM CWORKOUTS JOIN IWORKOUT ON IWORKOUT.WORKOUTID = CWORKOUTS.WORKOUTID AND DATE = '%@'", [BIUtility todayDateString]];

然后你做

[query release];

query的保留计数为0，因此会被取消分配。但是在自动发布池中仍然有对它的引用。然后，当稍后自动释放池耗尽时，它会尝试执行

[query release];

也是。由于对象已经被释放并且指针现在无效，因此您获得EXC_BAD_ACCESS。

NOOB内存问题 - EXC_BAD_ACCESS（OBJ-C / iPhone）

3 个答案: