由於未捕獲異常而終止應用程序'NSInternalInconsistencyException？任何線索？

Question

這裏是我的代碼，我現在使用，但仍然得到各種錯誤：

No visible @interface for 'HomeViewController' declares the selector 'getCount' 

而且

/Volumes/Lex/HomeViewController.h:12:12: Required for direct or indirect protocol 'UIPickerViewDataSource' 
/Volumes/Lexar/HomeViewController.m:15:17: Incomplete implementation 

我的代碼（.m文件）

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    PFUser *currentUser = [PFUser currentUser]; 
    if (currentUser) { 
     NSLog(@"Current user: %@" , currentUser.username); 
    } 
    else { 
     [self performSegueWithIdentifier:@"showLogin" sender:self]; 

     self.pickerView.dataSource = self; 
     self.pickerView.delegate = self; 
    } 
} 

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent: (NSInteger)component 
{ 
    if ([self getCount] == 0) 
     return 1; 
    return [self getCount]; 
} 

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:  (NSInteger)component reusingView:(UIView *)view { 
    if ([self getCount] == 0) 
     return nil; 
} 

- (IBAction)logout:(id)sender { 
    [PFUser logOut]; 
    [self performSegueWithIdentifier:@"showLogin" sender:self]; 
} 
@end 

和標題

/// .h controller 

#import <UIKit/UIKit.h> 
#import <Parse/Parse.h> 

@interface HomeViewController : UIViewController <UIPickerViewDataSource, UIPickerViewDelegate> 

@property (strong, nonatomic) IBOutlet UIPickerView *pickerView; 

- (IBAction)logout:(id)sender; 

@end 

Answer 1

正如您在評論中提到的那樣，您只需要放置UIPickerView ...但對於使用選取器視圖，您需要設置數據源（如UITableView），並且必須實施所有@required方法。

在選擇器視圖的數據源的協議中，有2種@Required方法

// returns the number of 'columns' to display. 
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView; 

// returns the # of rows in each component.. 
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component; 

所以，你需要實現上述控制器（比如說MainViewController）兩大方法。不要忘記設置這個類作爲委託和數據源，以UIPicker觀點如下

在ViewDidLoad的MainViewController

self.yourPickerView.datasource = self; 
self.yourPickerView.delegate = self;