iOS：重置 UIPickerView EXC_BAD_ACCESS 错误

Question

我正在使用 PickerView 来选择值，并且我想在按下按钮后重置它（因此它不显示之前的选择）。

问题是我总是遇到两个错误之一，它从一个运行到另一个运行变化，没有明显的模式。

有谁知道可能导致错误的原因，分别如何解决问题？

代码：

NSString * chosen;
NSString * elemString;
NSMutableArray *secondTableArray ;
NSInteger p = 0;
@implementation LagerViewController
@synthesize requestObject;
@synthesize choosenDocKind;
@synthesize pickerView1;

#pragma mark - View lifecycle
- (void)viewDidLoad
{
    [super viewDidLoad];
    secondTableArray = [[NSMutableArray alloc] init];
    secondTableView.scrollEnabled = YES;
    secondTableView.bounces = YES;
    elemString = @"";
    choosenDocKind = [[NSString alloc] initWithString:@""];
    [pickerView removeFromSuperview]; 
}

- (void)tableView:(UITableView *)theTableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    if(pickerViewItems != nil)
    {
        [pickerViewItems release];
        pickerViewItems = nil;
    } 
    if((indexPath.section == 1)&&(indexPath.row == 0))
    {
        NSString * temp = [[NSString stringWithFormat:@"%@",elemString] copy];
        NSString * tableString;
        if([temp length] == 0) {
             [secondTableArray removeAllObjects];
             [secondTableView reloadData];  
             elemString = [[NSString stringWithFormat:@"ARTIKEL: %@ %@ %@", matchcode, quantity, choosenDocKind] copy];
             tableString = [[NSString stringWithFormat:@"%@ %@ %@", matchcode, quantity, choosenDocKind] copy];

             // THESE 2 ROWS BELOW CAUSE THE ERRORS
             [pickerView reloadAllComponents];
             [pickerView selectRow:0 inComponent:0 animated:YES];
        }
    }
    [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO];
    [theTableView deselectRowAtIndexPath:indexPath animated:YES];
}

#pragma mark - button events
- (IBAction)btnSubmitPVSelection:(id)sender
{
    if([choosenPrompt isEqualToString:NSLocalizedString(@"DOCUMENT_REQUEST_LAGER_UM", nil)])
    {
        if(choosenDocKind != nil)
        {
            chosen = choosenDocKind;
            [choosenDocKind release];
            choosenDocKind = nil;
        }
        choosenDocKind = [[[NSString alloc] initWithString:[pickerViewItems objectAtIndex:[pickerView selectedRowInComponent:0]]] retain];
    }
    [tvArchDocParam reloadData];
    if(choosenPrompt != nil)
    {
        [self.presentedViewController dismissViewControllerAnimated:NO completion:nil];
        [choosenPrompt release];
        choosenPrompt = nil;
    }
    [pickerView reloadAllComponents];
    [pickerView selectRow:0 inComponent:0 animated:YES];
}

.h

@interface ... {
    DocRequest *requestObject;
    NSArray *pickerViewItems;
    NSString *choosenPrompt;
    UITextView *matchtext;
    IBOutlet UITableView *tvArchDocParam;
    UIAlertController *actionSheet;
    UITableView *theTableView;
    IBOutlet UITableView *secondTableView;
}   
@property (nonatomic, retain)DocRequest* requestObject;
@property (nonatomic, retain)UIPickerView *pickerView1;
-(UITableViewCell*)getSelectorCell:(NSString*)CellIdentifier;
-(UITableViewCell*)getTextFieldCell:(NSString*)CellIdentifier;
-(void)showPickerView;

错误：

1. Thread 1: EXC_BAD_ACCESS
2. Terminating app due to uncaught exception 'NSInvalidArgumentException', reason NSDictionaryM reloadAllComponents

Answer 1

首先也是最重要的——停止使用手动内存管理。

关于崩溃的第二个问题，看起来两者都与崩溃相关并且由同一问题引起（由于您给我们的代码，无法猜测究竟是什么导致应用崩溃），显然您的 pickerView 是在 [pickerView reloadAllComponents] 之前的某个地方发布的；被称为。

可能是因为[pickerView removeFromSuperview];例如，在 viewDidLoad 中，如果您指定了 pickerView 或类似的东西。