我对Xcode来说几乎是全新的。我正在尝试从sqlite3数据库中检索艺术家的信息。以下是我插入艺术家的地方：
- (IBAction)addArtistButton:(id)sender
{
NSString *artist_Name = artistFirstNameField.text;
NSString *artist_LastName = artistLastNameField.text;
NSString *artist_Phone = artistPhone.text;
NSString *artist_Address = artistAddress.text;
NSString *artist_Email = artistEmail.text;
NSString *artist_Bio = artistBio.text;
NSString *artist_SundayHours = artistSundayHours.text;
NSString *artist_MondayHours = artistMondayHours.text;
NSString *artist_TuesdayHours = artistTuesdayHours.text;
NSString *artist_WednesdayHours = artistWednesdayHours.text;
NSString *artist_ThursdayHours = artistThursdayHours.text;
NSString *artist_FridayHours = artistFridayHours.text;
NSString *artist_SaturdayHours = artistSaturdayHours.text;
int SunOn = artistSundayOn.on;
int MonOn = artistMondayOn.on;
int TueOn = artistTuesdayOn.on;
int WedOn = artistWednesdayOn.on;
int ThurOn = artistThursdayOn.on;
int FriOn = artistFridayOn.on;
int SatOn = artistSaturdayOn.on;
if (sqlite3_open([dbPathString UTF8String], &artistDB)==SQLITE_OK) {
NSString *insertStmt = [NSString stringWithFormat:@"INSERT INTO ARTISTS(NAME, LASTNAME, PHONE, ADDRESS, EMAIL, BIO, SUNDAY_HOURS, MONDAY_HOURS, TUESDAY_HOURS, WEDNESDAY_HOURS, THURSDAY_HOURS, FRIDAY_HOURS, SATURDAY_HOURS, SUNDAY_ON, MONDAY_ON, TUESDAY_ON, WEDNESDAY_ON, THURSDAY_ON, FRIDAY_ON, SATURDAY_ON) values ('%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%s', '%d', '%d', '%d', '%d', '%d', '%d', '%d')",[artist_Name UTF8String], [artist_LastName UTF8String], [artist_Phone UTF8String], [artist_Address UTF8String], [artist_Email UTF8String], [artist_Bio UTF8String], [artist_SundayHours UTF8String], [artist_MondayHours UTF8String], [artist_TuesdayHours UTF8String], [artist_WednesdayHours UTF8String], [artist_ThursdayHours UTF8String], [artist_FridayHours UTF8String], [artist_SaturdayHours UTF8String], SunOn, MonOn, TueOn, WedOn, ThurOn, FriOn, SatOn];
const char *insert_stmt = [insertStmt UTF8String];
char *error;
if (sqlite3_exec(artistDB, insert_stmt, NULL, NULL, &error)==SQLITE_OK) {
// NSLog(@"Insert: %s", insert_stmt);
Artists *Artist = [[Artists alloc]init];
[Artist setNAME:artist_Name];
[Artist setLASTNAME:artist_LastName];
[arrayOfArtist addObject:Artist];
NSLog(@"Added artist");
}else{ NSLog(@"Uh Oh: %s", error);
}
sqlite3_close(artistDB);
}else{ NSLog(@"Unable to open artistDB");
}
}
以下是我现在所掌握的信息。
-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
{
UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"Cell" forIndexPath:indexPath];
//UILabel *label = (UILabel *)[cell viewWithTag:100];
UILabel *last = (UILabel *)[cell viewWithTag:200];
NSLog(@"arrayOfArtist: %@", arrayOfArtist);
last.text = [arrayOfArtist objectAtIndex:2];
[cell.layer setBorderWidth:2.0f];
[cell.layer setBorderColor:[UIColor whiteColor].CGColor];
[cell.layer setCornerRadius:20.0f];
return cell;
}
Right now those NSLog entries result in the following:
2013-12-09 21:26:22.855 InkStudiosNav[24585:70b] arrayOfArtist: (
"<Artists: 0x8ab96a0>",
"<Artists: 0x8abede0>",
"<Artists: 0x8abf010>")
2013-12-09 21:26:22.856 InkStudiosNav[24585:70b] -[Artists length]: unrecognized selector sent to instance 0x8abf010
2013-12-09 21:26:23.106 InkStudiosNav[24585:70b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Artists length]: unrecognized selector sent to instance 0x8abf010'
*** First throw call stack:
(
0 CoreFoundation 0x0182b5e4 __exceptionPreprocess + 180
1 libobjc.A.dylib 0x015ae8b6 objc_exception_throw + 44
2 CoreFoundation 0x018c8903 -[NSObject(NSObject) doesNotRecognizeSelector:] + 275
3 CoreFoundation 0x0181b90b ___forwarding___ + 1019
4 CoreFoundation 0x0181b4ee _CF_forwarding_prep_0 + 14
5 Foundation 0x011f38ed -[NSConcreteMutableAttributedString replaceCharactersInRange:withString:] + 39
6 Foundation 0x011f455a -[NSConcreteMutableAttributedString initWithString:attributes:] + 293
7 UIKit 0x004c9bc6 -[UILabel _setText:] + 97
8 UIKit 0x004c9d84 -[UILabel setText:] + 40
9 InkStudiosNav 0x000048ce -[SecondViewController collectionView:cellForItemAtIndexPath:] + 318
10 UIKit 0x0092ebc8 -[UICollectionView _createPreparedCellForItemAtIndexPath:withLayoutAttributes:applyAttributes:] + 257
11 UIKit 0x00930217 -[UICollectionView _updateVisibleCellsNow:] + 3677
12 UIKit 0x0093357f -[UICollectionView layoutSubviews] + 267
13 UIKit 0x00387267 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 355
14 libobjc.A.dylib 0x015c081f -[NSObject performSelector:withObject:] + 70
15 QuartzCore 0x03c392ea -[CALayer layoutSublayers] + 148
16 QuartzCore 0x03c2d0d4 _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 380
17 QuartzCore 0x03c2cf40 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 26
18 QuartzCore 0x03b94ae6 _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 294
19 QuartzCore 0x03b95e71 _ZN2CA11Transaction6commitEv + 393
20 QuartzCore 0x03b96544 _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 92
21 CoreFoundation 0x017f34ce __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 30
22 CoreFoundation 0x017f341f __CFRunLoopDoObservers + 399
23 CoreFoundation 0x017d1344 __CFRunLoopRun + 1076
24 CoreFoundation 0x017d0ac3 CFRunLoopRunSpecific + 467
25 CoreFoundation 0x017d08db CFRunLoopRunInMode + 123
26 GraphicsServices 0x037d09e2 GSEventRunModal + 192
27 GraphicsServices 0x037d0809 GSEventRun + 104
28 UIKit 0x0031cd3b UIApplicationMain + 1225
29 InkStudiosNav 0x000054dd main + 141
30 libdyld.dylib 0x01d6c70d start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
我正在尝试从表/ db中检索“NAME”和“LASTNAME”。谁能帮我？我一直在谷歌搜索几个小时，但显然我不是在搜索正确的术语或其他东西。
插入艺术家的代码工作正常，我使用SQLite3 Database浏览器查看了数据库条目。
答案 0 :(得分：1)
根据你的回溯，看来这行就是问题所在：
last.text = [arrayOfArtist objectAtIndex:2];
您在这里为last.text分配了Artists而不是NSString。你的意思是：
last.text = [[arrayOfArtist objectAtIndex:2] NAME];
或类似的东西？